RF Field Changes
James W. Searcy (WA5WRE)
on
October 14, 2005
View comments about this article!
Amateur's that have been in radio for at least 25 years should best view this article.
I myself have used Amateur Radio for both pleasure and research for 53 of my 59 years. As an Electronics Engineering and Amateur, I have looked at many sides of this hobby/profession. I know of changes in weather affect propagation, and seasons have their input, so knowing this for the better part of the 53 years, it has come to my attention (and possibly many others), that over the past years, communications has somehow been affected.
During the daylight hours, DX and short range communications seem to be OK, but in the evening, RF seems to be replaced with noise. The reason I gave a time span of 25 years, is because in that short period, I remember that regardless of time of day, some frequency was open. I remember having QSOs with stations all over the world, and going into the early hours of daylight.
I pose this then as my question: With the creation of HAARP and utilization of some of Nikola Telsa work, are we now playing with the atmosphere? Too many things are happening to be called "common". Weather conditions all over the world are experiencing things that have never been before. -- Climate conditions, rain, hurricanes, giant waves appearing out of nowhere, etc. Or is it just our Earth going through unusual changes?
I'm not the brightest individual in the world, nor am I an idiot, but it would appreciate other inputs to this question, pro or con.
Thank You, Jim, WA5WRE
This article has expired. No more comments may be added.
|
RF Field Changes
|
|
|
by KV4BL on October 14, 2005
|
Mail this to a friend!
|
|
Jim, your article is indeed timely!!!! How odd that you should write this as this has been heavy on my mind for several months and more so recently. Apart from a brief two year stint as a 2 year (non-renewable) Novice in the early 70's, I got my Tech Plus license in early 1996. When I got my first 2 meter ht a few months later, I was amazed at the conditions that I could partake of. It was a fairly normal, but nonetheless exciting, thing for me to hit repeaters 60, 100, or more miles distant with just a ht and the factory rubber duck antenna. When my (then) wife won a 2m mobile at a hamfest not long after that, we were able to hit the Greenville, SC Blue Ridge ARC repeater on 146.610 at least a couple of times a week from our ground floor apartment in West Columbia, SC and check into their net and talk with her grandmother (Elmer to both of us and many others, K4AOH). We did this with a Radio Shack 5/8 wave magnet mount antenna on a cookie sheet inside of our apartment amd running between 10 and 50 watts. The last several years, SC has seen rather severe drought and with it, a dwindling of any meaningful "conditions" on 2m. Last year, we began to get rain on a regular basis, again, but the conditions still have not improved. Hitting repeaters in any direction that are more than 30 miles away is very rare just about anytime anymore. For a while, I wondred if it might be that the repeaters in the upstate of SC, where I used to like to make a lot of contacts were not being properly maintained or if my equipment was starting to degrade in performance. Well I doubt that all of these machines would fall into disrepair at once and I have had new radios and antennas come and go and that wasn't the problem. Also, I noticed that I can't make contact with the coast of SC as I once could. Yes, we get occasional brief bursts of propagation on VHF but it is very lackluster when compared to what we had a few short years ago. I, too, have pondered whether or not HAARP might be to blame for this and a multitude of "other" strange things going on in the atmosphere in recent years. I recall, even before getting my Tech Plus and also after, we used to get really thick heavy fog that I call "RF Friendly" as when it rolled in, you could hear some awesome skip on the VHF and UHF police bands as well as the ham bands above 144 MHz. Haven't experienced that in over 5 years. What happened???? I rarely pick up anything in the SC upstate above the white noise anymore. Even less to be heard from the SC coast. I have bounced this off of several friends and we get ideas from the weather changing patterns to sunspots, to whatever but none seem as likely to me as HAARP or similar efforts to monkey aruond with the atmosphere. Looking forward to yours and others' thoughts. 73, Ray KV4BL
|
| |
|
RF Field Changes
|
|
|
by YI9VCQ on October 14, 2005
|
Mail this to a friend!
|
If there truly is a "hole" in the ozone layer allowing a greater amount of radiation to reach the earth's surface then wouldn't that radiation cause some of the same effects you describe?
73,
Korey
YI9VCQ/KA5VCQ
Baghdad, Iraq
|
| |
|
RF Field Changes
|
|
|
by W2NSF on October 14, 2005
|
Mail this to a friend!
|
I believe the changes you hear in noise result from increasing anthropomorphic sources - in other words, sources of man-made noise that have increased in both number and power over the years.
The good news, if there is any, is that technology, especially receiver design, has also improved, so at least we amateurs have more tools in our toolboxes to fight this increasing problem.
I don't believe it'll go away, so I predict we'll be using more digital signal processing - both on the transmit as well as receive - in the future.
Jim
|
| |
|
RE: RF Field Changes
|
|
|
by K0BG on October 14, 2005
|
Mail this to a friend!
|
The internet has allowed all sorts of unsupported theories to become urban mythical in nature. It doesn't matter to most visitors that these theories are not peer reviewed; they're going to take them at face value regardless.
The debates about holes in the ozone layer supposedly caused by Freon, and global warming supposedly caused by our use of hydrocarbons are moot. We are, after all, coming off an ice age. Since modern man has never lived through one, the consequences, effects, phenomena, and other oddities can be, and are, supposition. Changes in radio propagation are certainly included in the aforementioned.
Most of man's knowledge is based on what he has observed in the past. In this case (radio propagation) is a little more than 100 years old. That's not much of a past when compared to the age of the earth.
Alan, KØBG
www.k0bg.com
|
| |
|
RF Field Changes
|
|
|
by N2XE on October 14, 2005
|
Mail this to a friend!
|
Maybe the laws of physics have been altered by some sort of sinister Teslian longitudinal wave generator. This is how the Russians altered the weather to create hurricane Katrina.
Perhaps Louis Farrakhan's "Mother Wheel" is responsible.
Global warming and the ozone hole must surely play a part in this--damn George Bush for not signing the Kyoto Treaty.
Corporate America and Big Oil have been conspiring for years to make annoying atmospheric static while reaping huge profits on the back of the "little guy".
Let us not forget what Art Bell and Tom Bearden have been waning us about all these years.
It has been reported that the Chupacabre beast can emit RF like interference so that need to be investigated.
I've noticed that propagation pratically ceases when that spectral locomotive runs down the abandonded tracks behind my house.
Or maybe you have a wall wart that's gone bad. That seems highly unlikely though...
|
| |
|
RE: RF Field Changes
|
|
|
by W1RFI on October 14, 2005
|
Mail this to a friend!
|
A few years back, at the QRP tent at the Williams, AZ hamfest, I was talking with Paul Harden, NA5N. Paul lives in a remote area of New Mexico, a really RF quiet area. He told me that one day, he was talking with a ham from the midwest, on 40 meters, when all of a sudden, the band went really quiet, but he station he was talking to didn't change in signal strength. The next morning, the local paper reported that, just as the band went quiet, there was a major power outage in southern California. Although anecdotal, it is pretty clear that the aggregate of man-made devices connected to the grid are raising worldwide noise levels.
How much is not quantified. Also, no one knows if this is essentially from the aggregate of millions of devices, or whether a smaller number of strong sources predominate. If I weren't so tied up in all this BPL stuff, I would love to investigate that with the mobile measurement set up I put together for BPL measurements. If we measure the noise in a typical town like Newington or Burlington, CT, we can get a per-capita noise level in the aggregate and run that EIRP level against the calculated IONCAP path losses and determine what the impact will be on distant areas.
ARRL did an IONCAP study that showed the reliability of HF at amateur power levels vs varying levels of man-made noise. It is pretty chilling to look at what the legal limit for unlicensed devices like BPL are calculated to do to HF.
Go to:
http://p1k.arrl.org/~ehare/bpl/ARRL_BPL_Papers.html
Exhibit C of the Notice of Inquiry filings is this IONCAP analysis.
Ed Hare, W1RFI
|
| |
|
RF Field Changes
|
|
|
by N4ZOU on October 14, 2005
|
Mail this to a friend!
|
|
Before Mount St. Helens blew it top on May 18, 1980 we were getting dire predictions of Global Cooling if we did not stop pollution and limit high altitude flights causing vapor trails that blocked the sun. Scientists predicted nuclear winters lasting year round killing all of us if nuclear war broke out. When Mount St. Helens blew it's top all these predictions were proven false. All the Chicken Little Scientists had to come up with something else to keep research money coming in the coffers so Global Cooling became Global Heating and dire predictions foretold of the ice caps melting and flooding New York and other cities, climate changes world wide causing crop failure and death if nothing was done immediately by the year 2000. Here it is 2005 and none of these dire predictions have come true and were still debating if there is any real Global Warming actually happening. Topping this is the discovery that Mars has heated slightly and that the sun is in a phase that�s just slightly hotter than what has been what we consider normal since we started keeping track of that sort of thing. Funny thing is I just heard on the news that some idiot has started spouting Global Cooling again! I guess his Global Heating money has run out, as, according to them, we should all be dead from Global Heating 5 years ago. http://www.fs.fed.us/gpnf/mshnvm/
|
| |
|
RF Field Changes
|
|
|
by WA3KYY on October 14, 2005
|
Mail this to a friend!
|
I suspect what you are now hearing in the evenings is all those millions of computers and TVs being turned on after dinner for the evenings entertainment. They all put out small amounts of RF noise but in the aggregate can raise the local noise floor several S-units. It is almost like a switch has been thrown at about 7pm local time.
73,
Mike WA3KYY
|
| |
|
RF Field Changes
|
|
|
by PATRICK526 on October 14, 2005
|
Mail this to a friend!
|
|
I think that it's not about climate change. The whole world is becoming more dependent on electronic equipment nowadays. Look at the proliferation of Wifi (802.11a-n), Bluetooth, cellphones, wireless phones, wireless garage door, key-less entry for cars, wireless entertainment centers, etc. etc... All these devices plays an important role in QRN because they are all emitting harmonics to different frequencies.
|
| |
|
RF Field Changes
|
|
|
by KB7LYM on October 14, 2005
|
Mail this to a friend!
|
Earth has gone through unusal changes since creation. othing can be done! Its called the living world. Or would you prefer a burned out cinder in space.Be happy ! We are not going to come out of it alive.
On the other hand.. transmissions from the Heavens might very well improve.But on the other hand ...once being in the Lucifers Amateur radio Club you might have some interference.If your Transmitter don't overheat.
Live with it.... there is NO OTHER WAY.
|
| |
|
RE: RF Field Changes
|
|
|
by KT8K on October 14, 2005
|
Mail this to a friend!
|
As a novice I sometimes thought I heard faint, echo-ey engine spark static on HF bands, even though there were no stations operating there. If I called CQ long enough, or someone else showed up and did, it usually turned out there actually was an opening, but nobody had expected it, so nobody was operating on the band.
I still believe (especially in light of my many years of QRP operation) that even small sources of noise can be propogated long distances on HF, and combine with all the other noise sources to raise the noise floor significantly - especially when a band is open. Other evidence of this is on the good old CB band. Flip across the channels and you will know when you hit channel 19 (the highway/trucker channel used by most of the operating stations on the band). Channel 19 has a subdued roar or noise, a measurably higher noise level than the other channels even when the band seems completely closed. Either through backscatter or some similar means, noise is propogated over long distances.
From my experience, the notion that a power outage in California would reduce HF noise levels far away makes all kinds of sense. I have long expected to see the noise levels on HF rising as population increases, BPL use is expanded, and more and more people buy those cheap-o electric blankets and lamp dimmers.
As for the VHF propagation, have weather changes, air pollution, or other causes reduced the frequency of temperature inversions and other duct-producing phenomena? Has tropospheric bending been reduced by changes in air quality?
These are good things to think and learn about, as we may (do) need to do something about them. The solutions will need to be implemented on a huge scale, and will be exceeding difficult to achieve. Start your lobbying engines, folks.
73 & best rx de kt8k - Tim
|
| |
|
RE: RF Field Changes are Bush's fault
|
|
|
by W9WHE-II on October 14, 2005
|
Mail this to a friend!
|
Its clear that Global Warming is the cause and Bush, Cheny and Haliburton to blame. As you know, Bush refused to sign the Keyoto protocol. This refusal is the cause of global warming, destruction of the ionosphere and the earthquake in Pakastan.
1) Global warming:
Cheny and Haliburton produce fossil fuels,which, when burned, are the sole cause of planetary warming. While you might think the sun has a role in warming the earth, you would be operating under a delusion propiagted by Bush and Cheney. All those stories about alternating ice ages and thawing over thousands of years are just part of the Carl Rove's spin machine.
2) Damage to the ionosphere & Ham radio:
As the world's temprature increases, the ionosphere warms. This warming causes expansion of the ionosphere and a corrisponding decrease in density. The decreased density results in less signal being propigated. With less signal propigated, you get less signal in the receiver. At the same time, all of Haliburton's evil equipment causes an increase in electromagnetic noise. All of this is calculated to ruin ham radio and force all of us to use BGPL (Broadband over Gas Pipe Lines) which Haliburton has a patent on. Carl Rove, Bush & Cheney have a plan to do away with cable and DSL and replace them with Haliburton's BGPL at $200 per month. In fact, BPL is designed to make ham radio so unreliable, that you move to Haliburton's BGPL.
3) The earthquake in Pakastan.
The quake in pakastan is all Bush's fault. He and Cheney were using a secret millitary weapon to steer Hurricaines to poor black areas of Louisiana. But they forgotr to turn it off. Instead, it sent a concentrated beam of energy into space, where it bounced off secret oil drilling bases on the moon, and back down to Pakastan, where it heated the tetonic plate, causing release and the earthquake.
|
| |
|
RE: RF Field Changes
|
|
|
by W6TH on October 14, 2005
|
Mail this to a friend!
|
.
I can go back a few years on propagation, over 67 years to be exact.
Most years from 1936 up until 1990 were almost duplicate years and followed the 11 year cycle. However the last good years were in the year of 1990 when a mobile radio setup from California could put a 20 dB over 9 signal to the east coast (20 Meters), just the 100 watts to a Hustler mobile whip. In November 1990 I was able to work 100 dx countries both on cw and also 100 dx ssb (Ten Meters) with a swan 350 and a 2 element quad at 60 feet.
Since 1990 band conditions have decreased in propagation for those big strong signals and now has beome more or less sporatic conditions.
I lived in a very quiet location in the Mojave desert, no power line noise and such, however there were many times of this very heavy rash scratching noise that appeared from nowhere, at times blanking out all incoming signals, also causing my Icom 735 to send out a very raw ac note across the bands. This was mostly on the 20 meter band, not common to my other years.
To make a long story short, I do believe there is something going on with these big antenna systems located up and around the North Pole.
It has often been said, " men will eventually destroy themseles", how true, it can be seen.
73, W6TH...A non vanity call.
.:
|
| |
|
RE: RF Field Changes
|
|
|
by WI7B on October 14, 2005
|
Mail this to a friend!
|
"I suspect what you are now hearing in the evenings is all those millions of computers and TVs being turned on after dinner for the evenings entertainment. They all put out small amounts of RF noise but in the aggregate can raise the local noise floor several S-units. It is almost like a switch has been thrown at about 7pm local time.
73,
Mike WA3KYY"
Yes Mike, I think you're right. At 6:45-7:15 PDT, its like a noise switch is pulled and the ceiling falls with a thud. I noticed this is especailly true with the coming of Autumn, cooler weather, and fewer outdoor activities in the evening.
Sounds like TVs, plasma screens, PCs and their monitors, stereo and entertainment systems all arising from the dead.
73,
---* Ken WI7B
|
| |
|
RE: RF Field Changes
|
|
|
by K0IZ on October 14, 2005
|
Mail this to a friend!
|
My station is in the mountains of Colorado with virtually no noise sources anywhere close. Using 20 meters as an example: During a solar flare or at night with low solar flux (ie dead band), my noise floor is very very low. During the daytime with normal 20M band conditions I would estimate my noise floor to be about 6 to 8 db higher. That is still much quieter than most hams have.
I would assume that some of that increase is due to world-wide storms (lightning). Some is due to poor phase noise of PLL-type transmitters, spreading broad-band hash across the bands. Also more amplifiers than years ago, such that -50db IMD is now 10db or so louder. Other related cause would be misc distant RFI.
On the receive side, a poor phase noise receiver will also give the impression of more noise.
Most hams do not realize how RF noisy their environment is, mostly local noise. Some of my visitors are amazed how much quieter my location is, compared with theirs.
By the way, I came across two interesting web sites that show some long-term solar and global temperature charts. Check out http://www.pages.unibe.ch/products/overheads/pdfs/beer-sunspotcycle.pdf for a Yr 1600-2000 trend of sunspots. Looks like we can blame ol' Sol!
Also take a look at http://en.wikipedia.org/wiki/Geologic_temperature_record. Especially note the 5 million year global trend and the 540 million year graph.
Interesting stuff, maybe Bush isn't responsible after all??
|
| |
|
RE: RF Field Changes
|
|
|
by WB2WIK on October 14, 2005
|
Mail this to a friend!
|
I've been a ham for 40 years and have noticed some things, too...but not quite as you describe.
I surely note "local neighborhood" RF pollution is far worse today than it's ever been, for everyone who doesn't live far out in the country.
It certainly seems plausible that some of this is conducted back through the power grid and radiates a lot farther than we might think.
I think there's no question that global warming *and* global cooling has been going on for millions of years, and so far we have no way to control it.
There's a link between weather in our troposphere and propagation in our ionosphere because both are very influenced by the sun. As is practically everything on our planet.
But here's one that is a man-made problem for which I have no solution:
Overall, a lot of the signals we are trying to work, irrespective of band conditions, are weaker because they're being launched by lesser antenna systems than ever before.
40 years ago, my typical 20 meter contact was using a yagi or quad, or at the very least a good dipole strung between a couple of fifty or sixty foot tall trees. Very few hams were using "compromise" antennas, antennas in their attics, or antennas they had to hide -- as such, the antennas actually worked.
Today, it's common on any band (I'll use 20m again as the example) that my contacts tell me they're using attic-mounted dipoles, dipoles strung along five foot-high fences, indoor loops, greatly shortened verticals and all sorts of stuff that hardly works at all. As such, I'm straining to hear them, much more than I ever had to strain 40 years ago.
I think *this* is a HUGE factor, and can make the bands sound full of crappy, noise-laden signals simply because they're weak.
Contrast that to a major DX contest weekend, when half the signals on the band (the contesters) are using big beams on tall towers, and all of a sudden everybody's 40dB/S9 again.
Restrictive zoning, and worse, CC&Rs, are the cause of the crappy signals in many cases. It's a huge influence, just like the sunspot cycle.
WB2WIK/6
|
| |
|
RF Field Changes
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
Right off the bat I would say the authors assertion is uh,,,,, bold!
That’s a nice way of saying he is making a huge assumption with little fact!
I would ask him:
1) In this vast 25 year (chuckle) data collection span, what has been the :
A) Station gain of your receiving station (data collection point)?
B) Front-end gain of each comparative receiver?
C) What is the difference in dynamic range of each receiver used (probably for such “assessments” {chuckle} the most important question)?
2) Do you think a broader sampling might be better (like say at least as far back as the Maunder Minimum)?
3) Do you use different methods of working this DX (Shsssssshh, I know the rest of us do {said in a whisper})? I’m thinking of course of both E-layer, and F-layer {as well as a few others}, inclusive of even taking advantage of the D-layer when it is stimulated.
These are just a few off the top of my head thoughts {we won’t discuss Tropospheric Ducting, Trans-equatorial skip, or Thermal Inversion}. I mean these other things are “weather” related, but what do you mean by DX? A range of frequencies would kinda be a good consideration too, don’t’cha think?
I mean this is a serious scientific study, right?
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
For the first responder to this article, Ross Hull would I’m certain be staggered at your findings. I mean, what you have accomplished on VHF, simply puts years of his work to shame!
YI9VCQ, I think you meant to say ascribe, not describe.
W2NSF, while your input describes only one probable source and premise, it is much better and more accurate than the authors!
Alan, I think that may be the best thing I have ever heard you say!
N2XE, come now sir! I cannot allow your last assertion to stand! Simply poppycock!
W1RFI, an interesting assessment, and ARRL study! Especially when considered that you guys also thought that 1 Watt output transmitters on hospital rooftops (no rooftop height specified, and no antenna gain specified) on 5.6 GHz for nation wide marketed devices would pose no difficulties for any Amateur operations!
N4ZOU, yup! For the rest, read Lowell Ponte’s “The Cooling”
WA3KYY, another better premise!
Patrick526, probably more QRM rather than QRN but, hey, the ARRL is looking out for .00017% of our spectrum for us, thank god!
KT8K, Tim, yours is a much better assessment than the authors, and a better scientific study too!
Vito, I think you and I have a few different observations old friend! Suffice it to say, your observations are a heck of a lot better than the authors! Psssst, your preferred mode of choice also gives you about 8 to 12 dB advantage over most of us poor “phone men”! ;-)
K0IZ, stop sir, you must stop! I cannot stand to hear yet another, of these VERY few, rational responses!
Oh Steve, are you telling me I have to be “like these Ham’s out there” and put up a real tower? Come now, can’t I just use a magnet-mount on a cookie sheet for 20 Meters? Come on, be real, that da*n thing is so big it barely fits in my den! I’m thinking of just mounting “The Resonator” {kinda like an Arnold thing” directly on my “Antenna Tuner”. Isn’t that what such tuners were made for, I mean so that we would not have to use REAL antennas!
|
| |
|
RF Field Changes
|
|
|
by WA7NCL on October 14, 2005
|
Mail this to a friend!
|
The reason why you don't hear as many stations is that there are fewer active hams, especially on CW. The ham population is aging and that means not staying up all night to work 40m CW.
Compare activity and signals on a typical day vs. when a major contest in going. There are many strong signals and the bands are crowded when a contest is on.
I think with all the newer means (cell phone, email, web sites) of contacting our friends and fellow hams we use the radio less and less for routine communications. Instead we use it for contests and special activities.
Finally, I think we are dealing with our own human perception. It's 10 or 11 years since the last sunspot minimum and we all tend to forget how bad the HF bands get (compared to our rememberence of previous cycle peaks). Add this to the fact that the last peak was somewhat lack luster compared to the two that preceed them, and you are bound to have some disappointment.
We need some ways to rekindle some enthusiasm to increase activity levels on HF. Contesting (although much maligned by rag chewers), less traditional modes like PSK, and Rtty, and QRP and field operation help keep the old spark alive.
So stop looking for mysterious causes in the ionosphere. Start looking in the mirror. There is nothing mysterious going on.
|
| |
|
RE: RF Field Changes
|
|
|
by KT8K on October 14, 2005
|
Mail this to a friend!
|
If it's just the proliferation of noisy electronic devices, and the noise can propagate like any other RF signal, then the global noise level should be rising with population as well.
<Soapbox ON>
Over population worries me a lot more than just global warming or rising ocean levels. In the late '90's demographic experts pointed out that, given some pretty good estimates of the earth's capacity to provide food (about 7.5 billion), human population would exceed the food capacity of the world well before 2050. We passed 6 billion a few years ago, and I heard recently that we are adding 1 billion people every 13 years now. That won't mean global famine, but there will certainly be famine in many areas (North America has more food than it can eat ... for now).
Besides a continual upswing in electrical noise levels, I expect wars to increasingly break out over food, water, energy, and increasingly large movements of refugees. We in the US are currently using 25% of worldwide energy production (or something like that) while we have less than 5% of world population, but other areas of the world are catching up in per capita energy use (and noise production).
Big disasters like hurricanes create more and more deaths and damage, not because they are necessarily worse than in the past, but because there are so many more people and buildings in their paths. I recently learned that the water tables in the Arizona deserts have dropped from around 12 feet to over 100 feet down in the last few decades, and I didn't see a single low flush toilet while I was down there this year. What are people thinking?
I don't think I'll be around to see how it is all resolved, but a huge crisis driven by overpopulation is inevitable before 2050 unless we do something about it. Show me one major problem that, at its root, isn't driven by over population. Conservation measures will only delay the inevitable.
Only birthrate reduction and control will really address the problem. Otherwise, Mother Nature will address the problem as she does with other species that get out of control: their numbers are reduced by disease, environmental pollution, famine, conflict/war, and natural declines in birthrate caused by decreasing rates of fertility, increasing incidence of homosexual behavior (in mammals, for sure), increasing stress/mental illness, and other factors. Consider how big a part China's population control laws have improved their current economic prospects. Either we do something or Mother Nature will take care of the problem.
The appalling thing is that I have heard only the smartest liberal politicians talking about overpopulation, and that has been ignored by the press. The conservatives seem completely blind, and more interested in manipulating the masses with short sighted, diversionary tactics like exciting people about gay marriage and abortion so they can get reelected and make rich folks and corporations richer.
We need to start thinking, and thinking ahead, if we want to avoid a terrible global scenario for ourselves and our descendants. Gay marriage is fine with me - they're unlikely to have kids! But religions that encourage big families are doing nobody any favors.
So please fight the increase in electrical noise on the bands by weighing in against overpopulation with your government representatives.
http://www.populationconnection.org/
<Soapbox off>
Best rx & 73 de kt8k - Tim
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by W6TH on October 14, 2005
|
Mail this to a friend!
|
.
I can prove that the ionization, etc can be chamged by theory and math, but there will be few that will be able to follow my math calculatons.
In my opinion, I honestly believe there are experiments, (A test under controlled conditions that is made to demonstrate a known truth going on with our ionosphere).
Ionization, Recombination, and Attachment
An electrical discharge is produced when gas molecules or atoms are ionized by electron impact. In the absence of losses, the change in the electron density is given by:
Calculus, higher math which most will not follow so will just leave it as it is.
My opinion for this experiment is to weaken, destroy "a" military action without the loss of life.
73, W6TH.... Not a vanity call...
.:
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
An electrical discharge is produced when gas molecules or atoms are ionized by electron impact.
-----
Well that explains last night's dinner but what about these changing RF fields?
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by ICOMTECH66 on October 14, 2005
|
Mail this to a friend!
|
I believe its George Bush's fault -- not only does he hate Black people but he also hates ham radio operators...
I mean -- if he can cuase hurricane to go where he wants then why couldn't he also cause the propagation to change....
.
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
ICOMTECH66, I think you are correct sir! Afterall, didn't Louis Farakahn tell us that G.W. blew up the ionosphere about the same time he blew up that levy?
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by W6TH on October 14, 2005
|
Mail this to a friend!
|
.
what about these changing RF fields?
Radiofrequency (RF) fields are part of the electromagnetic spectrum. For the purpose of the International EMF Project, such fields are defined as those within the frequency range 10 MHz (or 10 000 kHz) and 300 GHz. Natural and human-made sources generate RF fields of different frequency.
Common sources of RF fields include: FM radio (30 - 300 MHz), mobile telephones, television broadcast, microwave ovens, medical diathermy (0.3 - 3 GHz), radar, satellite links, microwave communications (3 -30 GHz) and the sun (3 -300 GHz).
RF fields are non-ionizing radiations (NIR). Unlike X-rays and gamma rays, they are much too weak to break the bonds that hold molecules in cells together and, therefore, produce ionization. RF fields may, however, produce different effects on biological systems such as cells, plants, animals, or human beings. These effects depend on frequency and intensity of the RF field. By no means, will all of these effects result in adverse health effects.
RF fields above 10 GHz are absorbed at the skin surface, with very little of the energy penetrating into the underlying tissues.
Who was it that mentioned Bush and his weapons of masterbation?
73, W6TH... This is not a vanity call.
.:
|
| |
|
RF Field Changes
|
|
|
by W2WO on October 14, 2005
|
Mail this to a friend!
|
I have consistently used CW since 1959 and have been fortunate enough to have had fairly good receivers and moderately good antennas. I am also fortunate to live in the "far suburbs" where local noise is minor (as far as I can tell). The long-term increase in background noise on 80 & 40 over they years is apparent. The "shape" of the noise seems to have changed also. I seem to remember a more "even" white noise in earlier years.
The noise growth on 20-10 meters is not as apparent to me.
My conclusion: zillions of small sources spread over most of the earth. Nothing we can do about it. Long term conclusion: ham radio will become much more VHF centered. I hope reasonable HF operation lasts the rest of my lifetime, but the fantastic explosion of digital and switching devices makes this unlikely. The reluctance of the FCC to enforce product conformance does not help, but that is secondary to the sheer number of devices all around us.
|
| |
|
RF Field Changes
|
|
|
by KE7ATE on October 14, 2005
|
Mail this to a friend!
|
I too have noticed the increased noise levels in just the past 20 years. I have been a ham since 1996 and have noticed a change in the radio environment of the spectrum. However, I would have to agree that much of the problem may be found in the increased use of electrical devices in the development of the modern world.
The increasing number of electronic devices that have appeared in the past 100 years is staggering. Electricity is the increased or elevated motion of electrons and when you get that many electrons moving it will cause electrical interference, AKA 'noise'. Also, the increased sensitivity of radio equipment as it has progressed in the last half of the 20th century has created the opportunity for everyone to 'hear' this increased noise level.
We are not the only ones experiencing problems with terrestial noise.
Astronomers are seeking support for cities like Phonix and Chicago to reduce the amount of light used at night, aka 'city shine' so that they can promote better astronomical observation opportunites. Turning off a few lights to improve the 'noise' level increases our chances of exploring our natural resources (the ionosphere, the universe, etc.)
I like to examine what some of the Old Timers did to improve their noise levels.
Consider the source of the noise and try to reduce any local interferences. As amatuer radio persons, we take careful measures to reduce any TVI or other interferences to maintain our hobby within the confines of today's world of poorly shielded devices and fussy household appliances.
Some of these comments on this subject have noted the increased use of Digital Signal Processing (DSP) and I must agree it can help with offending band noise, but I would like to encourage fellow amateurs to also examine their antenna installation, connections, and particularly grounding techniques.
I have seen some very sloppy construction techniques that may create some terrific results and keep the neighbors happy, but the band noise is barely tolerable.
Now, I say all this after sitting in my Toyota Tundra truck with my FT-817ND, plugged into my lighter socket and contacting N1PGT located just north of Carson City. The engine noise from my engine was awful, but I wasn't trying to fix the noise problem, I just wanted to see if the antenna was working as it should (PAC-12 antenna). (See my web site if you are interested in the details)
http://ke7ate.tripod.com/
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
Vito, do gay folks do that?
And if they do, will that help ionization?
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by KV4BL on October 14, 2005
|
Mail this to a friend!
|
|
WA6BFH, I know that my observations are not "scientific" per se, but the bottom line is that something has gone really crummy with VHF and UHF propagation in my neck of the woods. It has been this way for over 5 years now and I have made changes to radios, antennae, and feedlines and it is not the equipment. Several of my friends who were licensed at about the same time as myself have noted it this phenomenon also. The solar cycles generally are affecting hf, as I understand it, and not so much on VHF / UHF. As I was an avid scanner listener and utilized VHF / UHF equipment on the job for the last several decades, I know that decent (and sometimes annoying) propagation was to be found on a very regular basis. "Something", has caused it to be almost unheard of in the last five or so years. I am not prepared , nor do I have the time or inclination, to offer a "scientific" dissertation on why this is. I would like to hear others' input, though. To Tim, KT8K, you have hit the nail on the head regarding our overpopulation! It is really sad just how blind the majority of people are to overpopulation and the toll it takes on the ecology and quality of life for all of us. I don't understand why it is necessary to have three kids (or more) when two (or less) should do. Two produced by one man and one woman should be somewhere close to zero population growth. Besides the loss of wilderness and places to go to "get away from the crowd", one of the most obvious detrimental effects is the enormous increase in traffic on the roadways. Yet, government encourages unchecked reproduction by giving tax breaks for having more kids rather than taxing in proportion to the demand created for services like schools, roadways, water and sewer, etc. Will they ever wake up? Probably not.
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
KV4BL, you too should read the e-ham article that I wrote titled, "Black Sky"
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by W6TH on October 14, 2005
|
Mail this to a friend!
|
.
WA6BFH
Vito, do gay folks do that?
And if they do, will that help ionization?
John, in my engineering notes I cannot find anything in regards to gay folks. I don't think it was known in my time. Keep abreast and never know what will turn up.
As the world turns, never know where it will stop.
73, W6TH.. the non vanity call.
.:
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by AA4PB on October 14, 2005
|
Mail this to a friend!
|
Bush doesn't hate hams. He just cancelled the propogation so hams couldn't help counter the devistation from the hurricanes he caused. He'll turn the propogation back on as soon as he gets a round tuit.
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by W4JLE on October 14, 2005
|
Mail this to a friend!
|
The real problem is the "clean air" laws. We no longer have the lead particulates in the air to reflect VHF signals.
The lead floats in the air by the same physics that allows heavier than air CFA's to climb to extreme altitudes and eat up the ozone.
I actually was told by Big Foot last night that the whole thing is caused by CBers running 50KW amplifiers. The story is that 27 Mcs was used for diathermy years ago to heat sore muscles. It was thought that the change from Mcs to MHz would change the way these frequencies behaved. A new government study has been awarded to UCLA to determine the reason for failure. (2.1 Billion Dollars).
We just have to keep convincing the uninitiated that it is a sun spot cycle.
|
| |
|
RE: RF Field Changes
|
|
|
by W4VR on October 14, 2005
|
Mail this to a friend!
|
|
The noise levels certainly have increased over the years...and most of it is man-made (part 15 devices, OTHR's, etc.)...some of it is also due to changes in solar activity. At night on 40 meters I sometimes see broadband noise bring the noise floor up 20 dB on the PROIII scope..it slowly rises then slowly decays...I see this at both my Maine and Virginia QTH's.
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
Ok guys, I’m betting that anytime now, we are gonna hear from:
1) Scream’n Howard Dean
2) Calypso Lewie
3) The inventor of the Internet, the revered Al-Gore
4) Edward Kennedy (probably not too coherently)
5) Noam Chomsky
6) Jerry Brown Jr.
7) Rachel Carson
8) Edward Abbey (No, he would have more on the ball, and is also an SK)
Did I miss any really scientific tree huggers out there?
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
The noise levels certainly have increased over the years...and most of it is man-made.
True..., and what about those times I have pulled up to a traffic light and heard people playing those loud stereo's lately.
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by W6TH on October 14, 2005
|
Mail this to a friend!
|
.
If it should happen that we lose our vice president, does this mean we have a new vice president called Rice?
.:
|
| |
|
RF Field Changes
|
|
|
by G0GQK on October 14, 2005
|
Mail this to a friend!
|
Hello Jim,
Many replies to your questions but only a few of them are giving you some answers to your question.
First, the climate change which newspaper and TV reporters keep mentioning. The earth has been relatively quiet in the last few years and because people forget, and people die, the disasters of the past are forgotten. Can anyone ever recall reading about the 1908 disaster in Sicily when an earthquake stuck at 05.20, there were waves of 40 feet and 100,000 died. I doubt it. What about Krakatoa ? Where's Krakatoa ?
Going back further, could you imagine what early man must have thought if he was standing on a headland either in Spain or in Africa watching the Atlantic Ocean. The ice was melting, the sea became higher and with billions and billions of gallons of water it cascaded over the land through the Strait of Gibralter and formed what is now the Mediterranean Sea. And that, is just one event in the lifetime of the Earth.
Having got climate change out of the way, lets get to what you were discussing. For those who were not listening or talking on amateur radio 30 years ago, the radio conditions have changed, and quite dramatically.
I can recall that during the 1980's, 20 metres at lunchtimes in the UK, 12.00 -14.00 hrs. was humming with activity and can recall sitting in my car listening for a long time to the station in Alert on Ellesmere Island, pulling in stations one after the other. It was so busy with "Big Gun" stations that if you were not running maximum power with a monobander you didn't stand a chance of finding a space to call, even if anyone could hear a 100 watts station !
I also remember listening at home on my Hammarlund SP-600 US stations hammering in to the UK night after night, 5/9, even from California. It happened so frequently that I got bored with listening after 23.00 hrs !
I've spoken to old timers, now long gone, who recalled talking round the world on AM with 6-10 watts, and how they used to listen to taxi drivers in the US talking on 10 or 11 metres, as clear as a bell !
Of course it wasn't always as good on the bands. I recall being told that the RAF used 3.680 Mhz for their communications during WW2 and the first time that an eruption on the sun caused a radio blackout.
As far as radio is concerned, these were the early days, and such a blackout in communication had never before been experienced. It caused such a panic because of the loss of communication, the top brains in the government began to believe that Hitler had developed a secret ray which was able to kill radio communication. Of course it also happened to the German military, and they in turn believed that Britain had invented a device which would stop all their communications.
Some time last year there was an article in a science magazine which suggested that not only did the sun have a period of about 11 years when the poles reversed, it also had a longer period of about 5,000 years when the sun gained or lost its power. The author suggested that the sun at the present time is about three quarters of its way into a decline, and that this is why we, as amateurs, have observed this decline.
During this cycle it will have been noted that there has been very little EAST-WEST propagation, what little there has been has been poor compared to the previous cycle. I can recall 15 metres being in excellent condition with a sunspot count of only 90 in 1987, and the first time I ever spoke to CA, I spoke to about 10 stations in San Diego, because the footprint was so small.
There used to be Sporadic E on 10 metres during the Summer when I could speak into Germany from the UK every evening, and the strange thing was it was always to the same area in Germany, at 5/9+20 ! Dont hear about Sporadic E on 10 any more.
I often wonder if any other people listened to the noises produced by the Sun or other unknown heavenly bodies, I don't believe many did. I used to follow noises which appeared on the band until they disappeared into the ether, they were called band opening and band closing noises. There were other strange warbling, gurgling noises, and one that sounded like the waves on a beach passing through pebbles, all coming from space.
This business of the noise of TV's and computers affecting amateur radio frequencies when they are turned on and off is only a local thing. Suggesting that it is affecting everyone over long distances is doubtful. Really it makes about as much sense as suggesting that because everyone in the next town are shouting as loudly as they can, that the noise they are creating is making it difficult for you to hear what your wife is saying while you sit in your house 3 miles away !
I summing it up, I believe that band conditions have deteriorated during the last 30 years, big antennas or no big antennas.
73, Mel
|
| |
|
RE: RF Field Changes
|
|
|
by W9OY on October 14, 2005
|
Mail this to a friend!
|
You know it REALLY helps? Fashion a helmut out of tin foil. It cuts down on the noise a LOT.
73 W9OY
|
| |
|
RE: RF Field Changes
|
|
|
by K2WH on October 14, 2005
|
Mail this to a friend!
|
WA7NCL:
"Add this to the fact that the last peak was somewhat lack luster compared to the two that preceed them"
Excuse me, but the last peak was historic in its breadth and depth with its amazing ability to provide worldwide vhf propagation. 6 meters was the best DX band for about 2 months even better than HF!
K2WH
|
| |
|
RE: RF Field Changes
|
|
|
by W9OY on October 14, 2005
|
Mail this to a friend!
|
You know what REALLY helps? Fashion a helmut out of tin foil. It cuts down on the noise a LOT. Even better get an old galvanized bucket and wear that. You'll cut down on the noise and you get a nice echo effect when you speak into the mic.
73 W9OY
|
| |
|
RE: RF Field Changes
|
|
|
by K2WH on October 14, 2005
|
Mail this to a friend!
|
Forget the foil hat. This works better, "Get an Unlisted Head".
K2WH
|
| |
|
RE: RF Field Changes
|
|
|
by W5HTW on October 14, 2005
|
Mail this to a friend!
|
Men will eventually destroy ham radio.
They have sure been working on that the past decade.
Ed
|
| |
|
RE: RF Field Changes
|
|
|
by ICOMTECH66 on October 14, 2005
|
Mail this to a friend!
|
WA6BFH
You missed Al Sharpton and Jesse Jackson -- obviously this propagation problem is the white mans attempt to keep minorities off the air.
We all know that secretly the white follks have special radios and frequencies that the republican party gave them so they could communicate between them. What othr reason could there be but that for no ham radio operators operating out of New Orleans during the hurricane???
|
| |
|
Sapping and impurifying!
|
|
|
by KF6IIU on October 14, 2005
|
Mail this to a friend!
|
They are sapping and impurifying your precious bodily fluids. unless you are on a strict regime of distilled water and pure grain alcohol (many hams are doing this already!) radiation from HAARP (controlled by Hilary Rodham Clinton via FEMA's Airmail server (using PACTOR-III - a PROPRIETARY protocol!) may attempt to control your brain remotely!
Do you have any gold bullion in the house? Quick, before They can confiscate it, ship it in a plain brown wrapper to my address on QRZ.com!
|
| |
|
RF Field Changes
|
|
|
by NY4D on October 14, 2005
|
Mail this to a friend!
|
Sticking to the subject -
I always thought an rf field was something measurable around a radiating (whether by design or accident) rf device. But terminology aside:
Propogation is poor due to entering the bottom of the sunspot cycle. I started as a novice in 1964, when I moved to general in 1965 the sunspot cycle was at a low. Bands now seem about the same as then except for the manmade noise.
The sun has more to do with changing the background noise level than any other source. Check the geomagnetic conditions the next time you think it is especially bad. Can we spell unsettled?
The increased man-made noise from a myriad of new rf radiating devices does pollute the HF spectrum more than ever before. What used to be noise for me was car ignition spark and appliance and furnace motors. I hardly hear any noise like that any more. Now it is computer hash, rf from switching power supples, etc. Noise blankers don't work so well on this. DSP does though. I think most of this is local, but am willing to entertain the theory that some of it is radiated out through power lines and propogates into other locations.
Advanced military detection and communication systems in use worldwide increase the hf spectrum pollution. I hear a lot of funny signals that weren't there in the sixties. A lot more.
Newer signal reception techniques allow us to overcome most of this noise pollution. Insuring your transmitted signal is clean helps. Using proper power levels and adequate antennas for the desired signal path helps. QRO is necessary sometimes. A better antenna gives even more bang for the buck.
Conditions change. Adapt. But:
Do what you can. Write your congressman. Write Mr. Bush and ask him to replace the current "anything for a buck" FCC commissioners with engineers. Support the ARRL. You may not agree with all they do but do you know anyone else fighting BPL?
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
You know it REALLY helps? Fashion a helmut out of tin foil. It cuts down on the noise a LOT.
----
Thanks, I'll try that next time I am riding around in my car.
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
Do you have any gold bullion in the house? Quick, before They can confiscate it, ship it in a plain brown wrapper to my address on QRZ.com!
-----
I really hope you enjoy the chicken soup cubes I just sent, there sure was a lot of them ...
|
| |
|
RE: RF Field Changes
|
|
|
by K2WH on October 14, 2005
|
Mail this to a friend!
|
According to Screwy Louie, its the mother wheel. The one he was beamed up to about a year ago and he spoke to the brother aliens.
K2WH
|
| |
|
RF Field Changes
|
|
|
by KG6WLV on October 14, 2005
|
Mail this to a friend!
|
People seem to complain about propagation on HF, but despite that we are heading into the trough of the sunspot cycle, I still hear quite interesting things:
An op in Bogota, Columbia, ragchewing with a ham in Japan on 17 Meters, and a station in Slovenia working a mobile op in Texas on 17, among many, many others. I think the propagation is adequate, assuming you make use of it. As others have noted, 10-meters is only "open" during contests... it's just not being used, but it supports long-distance propagation under good conditions. CERTAINLY 15-meters would work. No, it's not like it was a few years back, but it's not hopeless, either.
And yes, the noise floor is climbing, and no, it's not going to get better. There's just plain too much electronic junk out there, too many computers, too many antiquated electrical grids. Someone here made the assumption that power line noise, and other assorted racket from Southern California could not be propagated over long distances to an op's QTH in Arizona. That's absurd; is the writer suggesting that the ionosphere only propagates "good" noise like a 1-Watt QRP CW signal, but not the cumulative noise from a huge metroplex?
Re: VHF propagation, isn't it possible ground clutter from increased building contruction could also account for poor propagation? I also wouldn't be surprised if increased particulate air pollution attenuates or scatters VHF/UHF signals. And increased development and paving will almost certainly curtail the formation of the fog one writer referenced.
The global climate varies dramatically over long periods of time, and it is modulated by solar output. The Danes didn't colonize Greenland because it was an ice cap; there are records of wheat harvests there in the early part of the last millenium. HOWEVER, it is shortsighted in the extreme for people to assume that we have no impact on these cyclical phenomena. For example, we are altering the heat budget of this planet with development and deforestation, regardless of the effects of green house emissions.
Also, apropos of nothing in particular, in the late 60s, I had the singular experience of receiving WCBS in New York in the San Francisco Bay Area during late-afternoon summertime daylight hours on a 8-transistor pocket radio. THAT will never happen again, I'm sure. Why it happened that time I'll never know. For that reason, radio still fascinates me.
|
| |
|
RE: RF Field Changes
|
|
|
by WB6CVR on October 14, 2005
|
Mail this to a friend!
|
If you think it is the millions of computers and other electronic devices causing the interference, then try this: next time you have a major power failure, fire up your HF receiver using battery power and tune around the bands. When I've done this, I still hear the squeals, birdies, and other QRM that I've always heard.
I remember tuning the bands when I was first licensed in 1962 and hearing either atmospheric noise or RF signals. These days I hear lots more than just that.
|
| |
|
RE: RF Field Changes
|
|
|
by WB2WIK on October 14, 2005
|
Mail this to a friend!
|
An RF field is similar to a corn field except substitute RF for corn.
My previous comment regarding the average ham today using crappier antennas than at any time in the past is serious and results in a lot of the weak signals we hear on the bands, no matter what conditions are.
And Cycle 23's peak, which was a double peak, very broad and very intense, was as good as any sunspot cycle since the beginning of the radio age, except for Cycle 19. I agree with K2WH, I've been licensed for Cycle 20-21-22-23 (and looking forward to 24: the sooner, the better) and I cannot ever recall six meters sounding like it did in November 2001 at the peak of 23. Unbelievable.
WB2WIK/6
|
| |
|
RE: RF Field Changes
|
|
|
by WF7A on October 14, 2005
|
Mail this to a friend!
|
|
After extensive research on the subject, I've concluded that the cause of this problem are hams using fan dipoles.
|
| |
|
RE: RF Field Changes
|
|
|
by K3AN on October 14, 2005
|
Mail this to a friend!
|
Don't forget about those hams who are using NVIS antennas. Most of their radiation goes straight up, where it undoubtedly heats the ionosphere.
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
I still hear the squeals, birdies, and other QRM that I've always heard.
----
Maybe it really isn't an RF field your hearing. You don't happen to live near a farm...?
|
| |
|
RE: RF Field Changes
|
|
|
by WX4O on October 14, 2005
|
Mail this to a friend!
|
I have to agree about the super proliferation of every type of electronic devices and equipment causing extra and increasing radio noise. This more or less goes back to a theory I have, starting in the early 60's, that all of the worlds problems are caused by overpopulation. Food shortages, diseases,
the huge weight of tremendous population centers (i.e. 'big cities'). Political and religious problems.
The general downturn of morals. Some event or events are bound to happen, in my opinion sooner than later, that will thin the world population dramatically. I think a huge number of us have a general sense of foreboding. We feel it coming.
|
| |
|
RF Field Changes
|
|
|
by N0TONE on October 14, 2005
|
Mail this to a friend!
|
Having been active with radio nearly 80 years, I've been through several of the 11 year sunspot cycles.
Do not forget that we are at the bottom of a cycle at present. As such, you should expect very poor propgation on 14mc and above. Conditions are relatively good for 1.8mc and 3.5mc, but those are typically not QRP bands.
I have not heard the bands this poor ever before. In addition to the weak signals caused by the present propagation, it seems the proliferation of switching supplies in consumer products is killing us. In the past, the background noise on any band consisted mainly of the sound of lightning storms propagated from wherever. These days, the background noise is more of a steady hiss, far too loud to be simple Brownian processes.
Furthering evidence is that if you live outside a populated area and possess a rotary beam, you can detect sizable differences in noise level between aiming the beam at the city and away from it. I can not remember a time in the past when this was true.
In contrast to K0IZ's writing, there are not more amplifiers in use today, there are fewer. In the late 50s or early 60s, an ARRL poll showed roughly 80 pct of hams used amps. Today, I doubt that figure is above 20 pct. Most certainly, of the general purpose club to which I belong, I am but one of three members (out of a club of 200) that even owns an amp.
However, noise from amateur stations is in fact much worse than before. Today's solid state radios have really given up too much on RF performance. They have very poorly-conceived ALC systems, which are designed to protect the PA, not reduce IMD, and hams push them too hard. A 100W solid state transceiver barefoot, generates notably more IMD than a good, properly set up, tube rig into a 1.5kW final amp. You can tune across the bands and note this - the background noise level in the ham bands is notably higher than, say, 100kc above or below the band edges.
How much higher is this new noise level? I'd guess 15-20dB. My first heterodyne receiver was a homebrew project with an ARC5 VFO as the base. It received on 80 and 20 meters. It was relatively insensitive. On 80 meters, during the day, I heard a faint bit of background noise. At night, I heard background noise in abundance. This would be about 1960. Nowdays, on the very same receiver (which sensitivy is unlikely to have improved with age), on a similar antenna, I heard background noise 24 by 7. The difference on 20 meters has been more telling. Due to poor sensitivy 45 years ago, this receiver heard no background noise at any time on 20 meters. Presently, it hears background noise again 24 by 7.
The earth and the ionosphere are simply behaving similarly to how they behave every eleven years. Blessed for the topband mates, and cursed for the ten meter ops. However, mankind has found methods for generating RF pollution in quantities far too vast to ever hope to gain any semblance of control over.
AM
|
| |
|
RE: RF Field Changes
|
|
|
by W5GNB on October 14, 2005
|
Mail this to a friend!
|
All you guys are WAY OFF!!!
Any fool knows that all this niose is a conspiracy which has been designed by the BUSH ADMINISTRATION.
Shortly after the next election all this will repair itself. BUT that is only if a DEMOCRAT gets into office!!
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
A few of these comments here may well have inspired me to write yet another article, and no Scott, it will not be ONLY about VHF and above!
I am thinking that many Ham’s, even the few old timers that are around here to comment, have forgotten what the bands sound like near the bottom of the Sunspot Cycle. I myself am often lackadaisical about this, because most of the time I don’t care what goes on below 28 Mc! Ooops MHz.
For NotOne I can say, where I live, Sporadic E-layer DX works very well. I realize that this is subject to certain geographical locales but, we can all look up the E-layer, F-layer MUF (Maximum Usable Frequency) contour charts right? We can similarly look up the D-layer absorption contour lines for different world-wide geography.
For those oriented toward VHF, Ross Hull explains things much better than I probably could. But since he is now a Silent Key, and I am not, I may give that a whack to.
Don’t dispair guys, I think our next cycle peak will be quite Ok, maybe great! For those with cookie sheet antennas, and who are otherwise “loading up the bed springs” -- you too will then be able to talk -- for a couple of years anyway!
PS
NotOne, are you saying you did not own a super-heterodyne radio until 1960?
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
Hey Philip, Ross Hull. A good Ded for you!
Get up higher than those audio frequencies dude!
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
However, noise from amateur stations is in fact much worse than before. Today's solid state radios have really given up too much on RF performance.
-----
Kidding aside, I have to agree with your well written account indicating the past 80 years of radio observation.
I can definetly notice a difference in the recieve characteristics between solid state and tube rigs.
For example, my Yeasu FT 847 solid state rig attached to a switching power supply always seems to have a constant and steady noise that is generated as far down as the noise floor itself. It's really not noticable, but it's always there. In fact, it might be in all solod state equipment.
But when I turn on another rig in my shack say an R/390a, or a BC 348 radio, then I can hear things like distant static crashes, atmospheric noises and other disturbances that I simply cannot pickup on any solid state rigs. It's not like the recieved signals or the boatanchors recievers sensitivity are better than my solid state rigs, there not. It's just the background noise and the atmospheric sounds I can hear that's different.
What does that mean exactly? I don't know. But so far what you have said in your comments seems to fit the bill as far as my own experience goes.
73
Charles - KC8VWM
|
| |
|
RF Field Changes
|
|
|
by W1GUD on October 14, 2005
|
Mail this to a friend!
|
Hello...an interesting idea there.
I'm just a newcomer, only 40 years licensed come next august, but the bands sure sound more to me like the bottom of the sunspot cycle I've seen three times before.
I'm working all kinds of dx up through 15, though I can't wait till we've got the Collins 10 meter AM Net going again.
I just hope the 6meter action is as good as it was in the winter 1999-2000 peak when it comes around again six years from now!
The noise thing is easily explained, like a number of posters said, its just all that new electronic stuff out there.
And the QRN is nothing a high-end dsp rig won't cure. Now-a-days we can just turn the noise off. Couldn't do that 30 years ago.
My two cents.
73, Warren W1GUD
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
Charles, I think this noise you describe is “synthesizer phase noise” combined with the typically poor dynamic range of most solid state radios of our day.
It is a deal we made with the devil, when we said “low voltage portability, and durability, is more important than the dynamic amplification range and linearity of the vacuum tube rigs!”
|
| |
|
RF Field Changes
|
|
|
by N0XMZ on October 14, 2005
|
Mail this to a friend!
|
>"Weather conditions all over the world are experiencing things that have never been before. -- Climate conditions, rain, hurricanes, giant waves appearing out of nowhere, etc. Or is it just our Earth going through unusual changes?"<
Yes, weather patterns are changing. They alway have, this is nothing new. It may be different than it was in the 1950s, but it's no differant now than it was centuries ago. Earth has gone in and out of ice-ages all by itself, long before "greenhouse gasses" and "global warming", etc.
By the way, the last I checked, our atmosphere still consists of 79% nitrogen, 20% oxygen, and 1% other gasses - even though we've been burning fossil fuels for a century. Even still, if you listen to some of the environmental wackos out there, you'd think our planet is being suffocated in CO2 (oxygen-producing plants LOVE CO2, by the way). 100 years is nothing to a planet with an atmosphere that is hundreds of miles high and does an amazing job taking care of itself. If it's a little warmer this summer than you remember as a kid - who cares? Get used to it. It's all NATURAL.
As any meteorologist worth his weight in salt will tell you, weather cycles are far more grand than that of our own lifetimes. Our ancestors had vicious hurricane seasons too. Remember the 1930s dustbowl in Kansas? People spend way too much time worrying about things they cannot control, like the weather.
I had a conversation with someone on 40m, over 1000 miles away at around midnight last night. But didn't someone say 40 was "dead" at night?
Get over yourselves mortal humans! Screw the solar cycle minimum. Put down the mouse and call CQ dammit! :o)
-N0XMZ
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
Thanks John!
Synthesizer phase noise eh? You have just confirmed that just because my tube rigs have a vacuum does mean they suck.
(ooOO Note to self-: Yaesu spells devil if you look at all the letters just the right way.)
73 Charles - KC8VWM
|
| |
|
WB2WIK is right on with the crappy antenna stuff
|
|
|
by KF6IIU on October 14, 2005
|
Mail this to a friend!
|
Ok, we had our fun satirizing the tinfoil-hat crowd. Seriously, Steve is right on.
There is a philosophical principle called "Occam's Razor" which says that the simplest explanation for a phenomenon is often the most likely. So the simple theories work for me: The world is crowding together, and fewer and fewer of us are able to put up antennas more than a fraction of a wavelength high. IIRC, an astonishing percentage, more than 75%, of the new housing built in the US has CC&Rs with antenna restrictions. And it doesn't help that every single dang household in the world has a cheap-ass 29-cent Chinese halogen lamp dimmer that radiates S9+ at DC to daylight (ours knocks out our DSL line), and the noise propagates all over the world. That RF hash propagates just like anything else.
Proof for me was the previous poster's anecdote about the noise level going down when a faraway region suffered a power outage.
Well, I just got my DXCC with a 140-foot dipole up only 35 feet and a venerable FT-101E, less than 100W on its half-kaput old finals, with a few 10-meter mobile contacts from the tail-end of the last sunspot cycle. (Although I could not have done it without the big contest stations and their excellent QSL return rates. TU!) If I can do it operating as casually as I do, so can anybody else.
There are a million ways to work around the problem. CW, digital modes, portable QRP - and I've got 235 entities to go. Time to quit my bitchin'....
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
|
ok, let's try inserting the word "doesn't" between the words vacuum and mean...
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
K0IZ, that is a wonderful graphic, and piece of data you found!
I will see that a link is posted on our Tech Bench Elmers web page -- on the propagation sub-page.
You might want to take a look:
http://www.geocities.com/SiliconValley/2775/
Thanks, nice insights!
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 14, 2005
|
Mail this to a friend!
|
It often means the tube rigs are better than many (probably most) solid state rigs.
There are poor tube rigs too. There are some though, that will beat the pants off the best of the new rigs (psssst, even IC-7800's)!
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 14, 2005
|
Mail this to a friend!
|
The 390a is probobly a good candidate for a side by side comparison. Rick Mish sure knows how to make them sing.
|
| |
|
RF Field Changes
|
|
|
by W0SWR on October 14, 2005
|
Mail this to a friend!
|
|
I too wondered about why my radio hears so much noise these days and so little AM, CW, and SSB. After much thought on this problem, I consulted a couple wise and wonderful palm readers and the local weatherman. After several hours of heavy meditation, I think I have pretty much solved the problem and think this might help other radio operators. First I disconnected my Oriental transciever and put my Swan 350 back in line because there are certain countries out there that still hold a grudge against the U.S.A for a war long over. I then decided a bigger amp would help my signal get over the noise, so I went to the store and bought the biggest baddest amp I could find (with American parts). Then up the tower I went with new coax and a bigger antenna. The coax is a higher velocity coax so the signal would go faster than noise can travel. Then I used special antenna noise grease that I borrowed from a neighbor who is a CB specialist. I installed a wallwart noise filter just to be on the safe side. After a lot of sweat, WALLA! I turned the rig and linear on and I could hear stations on 15,20 and 40 mtrs. I glanced at the meter and it showed a low signal/noise level, and with the big caps across the speaker I heard little noise. Man I tell ya it was just like the 'old days' when there was no noise and great signals! I think I will try the Ten Tec next week. Sure gonna miss my 102. I hear the Chinese are coming out with a rig soon....can hardly wait!!
|
| |
|
RE: RF Field Changes
|
|
|
by WA4DOU on October 15, 2005
|
Mail this to a friend!
|
|
Steve's explaination is on target. If you want to work dx in abundance without the necessity of an amplifier, try cw.
|
| |
|
RE: RF Field Changes
|
|
|
by WR8D on October 15, 2005
|
Mail this to a friend!
|
|
I just don't know folks. I have a friend that lives in the headend of a canyon here in Wva. There are no large power lines running into there and he never has any noise at all and i mean "never". In the summer months he gets lightning crashes during storms but when the storms go away his noise also leaves. His s-meter sits on 0 and he can hear stations all over extremely nice. In this part of the country one never sees such a low noise floor and i think the power grid "radiates" extreme distances like someone has already mentioned. WR8D
|
| |
|
RE: RF Field Changes
|
|
|
by AA4PB on October 15, 2005
|
Mail this to a friend!
|
I don't know about more noise being generated in solid state receivers than tube receivers. It should be real easy to tell. If you have an S5 noise level with the antenna connected and the meter drops to zero when you disconnect the antenna then the noise is not being generated in the receiver.
There are probably multiple issues coming into play. Weaker signals due to propogation, more people with limited antenna installations, etc. On the other side, if you live in a built-up area then you have higher noise levels generated by power lines, computers, and various other electronics. Try driving around with an HF mobile. It will be a real eye opener. If I am on the main business road the meter reads noise at S9 to 10/9. When I drive a mile out of that area the meter will be setting on S1.
|
| |
|
RF Field Changes
|
|
|
by WY3X on October 15, 2005
|
Mail this to a friend!
|
Art Bats-in-the-bellfry and George Nooraninny stay up at night waiting for you to call, but you never do! <GRIN>
-KR4WM
|
| |
|
RE: RF Field Changes
|
|
|
by W8JI on October 15, 2005
|
Mail this to a friend!
|
I'm in a quiet rural location. Noise here increases significantly whenever any band is open to populated areas.
Noise also increases below 10 Mhz at night as tropical zone noises from thousands of lightning hits blends to make an almost "white" noise. Bands are noisier beaming across the tropic areas or any region with heavy thunderstorm activity.
I don't detect anything from things like HARP. Beaming NW it is pretty quiet. I sure hear noise propagated in from our major population centers, like when I look up along the eastern seaboard!
I'm positive radio noise pollution is significantly worse than it was years ago. It has to be, especially when a person lives in a city. I can't turn an AM broadcast radio on in my house and copy noise free local staions, let alone stations hundreds or thousands of miles away. If I want to receive noise-free standard broadcast band stations, I have to use an outside antenna hundreds ofr feet from my house.
I can't receive WWV's VLF time base signals on "Atomic Clocks". Once again I have to use an outside antenna located hundreds of feet from the house.
Despite being fussy about filtering in the electrical devices I purchase, my house is a pig pen of noise. I can't imagine it being any better for anyone else. Now add all the junk from every house in a crowded area, and it's only natural to have problems.
73 Tom
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 15, 2005
|
Mail this to a friend!
|
Darn, when folks here get more rational and reasonable in their thoughts, it sure takes the fun out of this thread!
|
| |
|
RE: RF Field Changes
|
|
|
by N5EAT on October 15, 2005
|
Mail this to a friend!
|
I agree that "WIK"'s contention that we are radiating and receiving with crippled antennae. However, one of the main problems at the moment are horrid band conditions and increasingly computer chip driven receiver equipment. I have a few pieces of Ten-Tec gear. These radios are combinations of older and newer receiver technology. Invariably, these Ten-Tec rigs are incredibly quiet compared to my other gear. They also don't push the limits of receiver sensitivity. Anything < .25 microvolts for 10db quieting is inviting hash, buzz, humm, and all sorts of useless junk you don't need or want to hear.
Of course, the millions of pieces of radiating consumer gear isn't helping. Flourescent lighting, bpl, the neighbor's heating and air conditioning. It's all noise. Top it off, this is the worst sunspot
nadir i've heard in 3 sunspot cycles. Conditions are simply horrid. Last week, for some unknown reason, conditions got really good for 2 days. On those 2 days, the noise levels dropped and signal levels went up. I think unless BPL wipes us all out, the next solar upswing will help us all feel better.
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 15, 2005
|
Mail this to a friend!
|
That was probably because of a big hole in the "chroma" of the Sun. Check out the propagation and science sub-pages of the Tech Bench Elmers web page.
|
| |
|
RF Field Changes
|
|
|
by N0AH on October 15, 2005
|
Mail this to a friend!
|
Jim,
Why would any cycle act the same if none of the curves are the same? For example, this cycle had a double peak to it and low bands have been, and still are,a lot worse then the previous cycle. I'm not saying your question is bad, but the answer seems to be in each cycle's wave pattern. That said, daily polar absorbortion factors on any given day also can change things in a much shorter realitve time frame. So some cycles have good days and bad days etc.....
|
| |
|
RE: RF Field Changes
|
|
|
by WA8MEA on October 15, 2005
|
Mail this to a friend!
|
Sounds like a topic for "Coast-to-Coast AM" with George...or Art...or Ian, with special guest Alex Jones who would blame George Bush for personally making the propagation bad.
I've been through four cycles, going into the fifth. None have ever been duplicated. 88's and 99's were two of the best. 77's peak just abolutely sucked weenies. Summer prop is never the same as winter prop, and spring and fall show characteristics of the previous season...and the season to come.
I still think ten meters could support several hundred QSO's this very afternoon. But because so many folks have been told "the band is dead", they won't even try.
Always remember that during the solar low, the MUF, Maximum Usable Frequency, goes down in frequency. So 160 meters is a fun band to play around on. Even 60 meters is fun this time of year, with many 50 watt transatlantic qso's taking place.
And if none of that trips your trigger, try Lowfering:
1750 Meters - 160 to 190 kHz. This may become a ham band soon. You can currently operate this traditional Lowfer band under FCC part 15.
Propagation is not dead. It's just moved around some.
73, Bill - WA8MEA
http://HamRadioFun.com
|
| |
|
RE: RF Field Changes
|
|
|
by WB2WIK on October 15, 2005
|
Mail this to a friend!
|
The high accuracy clocks that lock to the 60 kHz WWV signal don't work for me, either. At least not anywhere in the house. I might try a bigger antenna (zillion turn loop or something)...never thought the problem could well be "noise," but now that W8JI mentioned it, that probably is the problem.
I don't notice much difference if I use old tube type analog or modern solid state synthesized, when it comes to noise or signal-to-noise of received signals.
Although stations in distant rural areas likely do have lower overall noise levels simply because there's less stuff around generating noise, another "problem" is that so many stations nowadays are just plain using small and inefficient antennas which don't pick up much noise at all because they're small. However, they also don't radiate well. Used to be that "separate receiving antennas to improve signal to noise ratio" were things like Beverages that only 160m and 80m operators used; but nowadays, many stations on all bands are using them without even knowing it -- they are "low noise" antennas because they're "very small and inefficient" antennas, which pick up less of everything. If an antenna picks up noise 6 dB less than it picks up signals, then it will show a 6 dB improvement in hearing stations on HF. But almost all such antennas don't transmit worth a darn.
WB2WIK/6
|
| |
|
RE: RF Field Changes
|
|
|
by W8JI on October 15, 2005
|
Mail this to a friend!
|
Antennae are on insects.
Antennas are on our radios.
Example? John Kraus' book is called "Antennas", not "Antennae".
If you are using crippled antenae, it's probably just crickets making noise.
|
| |
|
RE: RF Field Changes
|
|
|
by W8JI on October 15, 2005
|
Mail this to a friend!
|
Low band receiving gear is virtually always noise limited by external noise. That noise power, being broadbanded, is directly proportional to receiver bandwidth.
It's a popular but generally untrue myth that some receivers, when connected to external antennas, are "quieter". As such we cannot buy a receiver that "reduces noise" unless that receiver also has marginal gain at low input signal levels. A receiver with a narrower IF filter will "quieter" because every 50% reduction in bandwidth reduces noise power 50% (3dB). This works until the receiver filter becomes narrower than signal bandwidth.
At HF, neither synthesizers or anything else except ultimate bandwidth of narrow filtering affect S/N. The exception is with very poor local oscillator design. When an extremely strong signal is in the passband it can mix with local oscillator noise and generate noise.
We can buy receivers that fall out of AGC at voltages above propagated noise levels. This will create an illusion that they are quieter, but that is only because they reduce volume as signal levels drop. If we measured S/N or tried to copy a weak signal, we would actually find them no better and perhaps worse tha a receiver that was holding the weak signal at or near normal volume levels.
In nearly all cases at HF, noise is external to the receiver. The only thing we can do about it is use a narrower ultimate filter bandwidth or increase antenna directivity.
73 Tom
|
| |
|
RE: RF Field Changes
|
|
|
by W6TH on October 15, 2005
|
Mail this to a friend!
|
.
Antenna, antennas, antennae. Antennae could be a typing error.
Antennae:
High Resolution HI Mapping of NGC 4038/9 (``The Antennae") and its Tidal Dwarf Galaxy.
.:
|
| |
|
RE: RF Field Changes
|
|
|
by W6TH on October 15, 2005
|
Mail this to a friend!
|
.
Antennae are really sensors:
The antennae are a pair of sense organs located near the front of an insect's head capsule. Although commonly called "feelers", the antennae are much more than just tactile receptors. They are usually covered with olfactory receptors that can detect odor molecules in the air (the sense of smell). Many insects also use their antennae as humidity sensors, to detect changes in the concentration of water vapor. Mosquitoes detect sounds with their antennae, and many flies use theirs to gauge air speed while they are in flight.
The sensors do not produce noise into ham receivers.
.:
A dipole antenna could be called a antennae if it is to receive and sense a signal. Right?
.:
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 15, 2005
|
Mail this to a friend!
|
What bands were you guys operating, that said the 1978 sunspot peak was bad. I have heard that twice now, and the first guy I know usually has his head where the sun shines!
I worked some of the best DX ever on 6 Meters during the '78 peak. I picked up several contacts into those little states, New Hampshire etc, where you never hear anybody, and also VP9 (from California). If the MUF is cooking up past 50 MHz, what do you think is happening lower?
Take a look at the graph the chap on this thread found.
http://www.pages.unibe.ch/products/overheads/pdfs/beer-sunspotcycle.pdf
The '78 peak was only a bit lower than the all time great peak of 1958. In fact, aside from '58, it is our highest sunspot peak EVER !
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by N6AJR on October 15, 2005
|
Mail this to a friend!
|
actually the increrase in noise is non existant. the problem is that the recievers have gotten much better and you can hear more.
I can tune my swan 350 and my orion to the same signal on the same antenna and the signal and noise is greater on the orion every time. better rx means you hear more...
DUH>>>
now go build a fan dipole..
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by W6TH on October 15, 2005
|
Mail this to a friend!
|
.
Yes, sensitivity and selectivity, much better than the old tube radios.
You will hear less noise on a 5 foot piece of wire compared to a 130 foot wire. A mis-matched antenna will produce less noise as well.
Going from a 5 Khz filter to a 250 Hz filter will also reduce noise.
.:
|
| |
|
RF Field Changes
|
|
|
by NC9K on October 15, 2005
|
Mail this to a friend!
|
I've noticed an S2 "hiss" level that comes and goes on the entirety of 20M depending on band conditions. I think this hiss is related to solar activity and borderline maximum usable frequency conditions.
Food for thought: The electric power industry is now creating super long broadband RF energy radiators with amplified BPL repeater RF linking of long segments of what used to be RF isolated (low frequency) power line segments. Like super sized multi-wavelength long wire antennas radiating ad-nausium whatever the BPL repeaters pick up. This would include strong powerline RF noise generated by noisy switching power supplies, computers, computerized washing machines, etc.
|
| |
|
RE: RF Field Changes
|
|
|
by SM0AOM on October 16, 2005
|
Mail this to a friend!
|
Having some 25 years almost daily experience of Air/Ground and tactical HF,
it it my firm belief that the received noise floor has increased due to various electronic systems that generate noise.
In the early 80's it was not uncommon to find an average noise floor of -120 dBm or lower in an SSB bandwidth, but 20 years later the same measurements
done in the 8 or 11 MHz aeromobile bands seldom go below -110 dBm. The receiver sites for Air/Ground HF are located in "quiet rural areas", and the noise increase appears to be largely due to ionospheric propagation from "hot spots" in Central or Western Europe.
It appears from the HF channel occupancy statistics gathered in the 80's and 90's by scientists at Univ. of Manchester and the Swedish Defence Research Establishment that the "dynamic range" has "shrunk" with about 20 dB, 10 dB due to an increased noise floor and with 10 dB due to lower power levels that currently are used in broadcasting and fixed radio services.
To blame the increase on "synthesizer phase noise" seems to me as an over-simplification, as this mainly comes into account at very high signal levels, or with very inferior synthesizer designs.
However, part of the problem can also be compounded wide-band emissions from transmitters operating both in the affected bands, and in adjacent bands.
In the light of observed transmitter sideband levels,
I have serious doubts of the practical useability of a +40 dBm IP3 receiver, and its implied 110 dB dynamic range.
73/
Karl-Arne
SM0AOM
|
| |
|
RE: RF Field Changes
|
|
|
by WX4O on October 16, 2005
|
Mail this to a friend!
|
RE: The comment about all the RF noise being
designed by the Bush Administration. Interesting.
But I thought it was designed by Al Gore - the 'inventor of the internet' - as a way to get
Democrats back into office. Now I'm confused! :)
|
| |
|
RE: RF Field Changes
|
|
|
by W6TH on October 16, 2005
|
Mail this to a friend!
|
.
I noticed that the Republican and the Democrat radios have most of the noise, but not so on the independent radios, the independent radios are at a zero noise level.
.:
|
| |
|
RE: RF Field Changes
|
|
|
by K8MHZ on October 16, 2005
|
Mail this to a friend!
|
It's simple...
More noise and radios that hear better.
Before I blamed the space aliens and the Bush Admin, I would start looking at the trememdous increase in radio controlled devices and non radio controlled devices that emit radio waves, millions and millions of them, all turned on at once.
Eventually we will figure out a way to make all these devices quiet. Until then we have to work around the issue. Some radiators, like poor electrical insulators, can be eliminated. Others will just have to be dealt with on the receiving end with changes in antenna design, modes and filtering.
But we will figure it out.
To brag a little...we just finished up a JOTA session. The location of the station was a cabin near Lake Michigan on a quite populated drive. The dunes that surround the cabin pretty much wipe out the cell phones. That was the case at JOTA. The Scout's parents could not call home, but we were talking to England like she was next door!
Sitting next to our HF rig was the VHF/UHF rig tuned to the club repeater which is outfitted with a phone patch. That is the only way to get a dial tone in that cabin, has been for many years and may very well be for many more. Last week we had a packet session and sent e-mail from the cabin for the first time...using ham radio.
Yes, the noise floor is increasing. But I am too busy with other parts of the hobby to do anything about it. I hope my counterparts will carry on the task!
73,
Mark K8MHZ
|
| |
|
RE: RF Field Changes
|
|
|
by G0GQK on October 16, 2005
|
Mail this to a friend!
|
Hello Jim,
Something else I recall from previous years was the band conditions on 80 metres. In the UK in the 1970's, and before, the propagation on the band was 500% better than it is now. It was open for contacts almost all day across the UK and I can remember when it changed, as probably can many others.
Everybody migrated to 40 metres whereas before 40 metres was used specifically for DX it now became the only band where people across the UK could converse with each other. In recent years 49 metres has changed and some days it is impossble to have inter UK contacts and the same conditions exist on 80 metres.
As a passing comment,it seems quite a number of people who have responded to your subject have either been smoking whacky baccy, have migrated to eHam from QRZ, were dropped on the planet by mistake, or perhaps didn't understand the subject to which they were responding.
73, Mel G0GQK
|
| |
|
RE: RF Field Changes
|
|
|
by WA8MEA on October 16, 2005
|
Mail this to a friend!
|
Maybe many believe 1977/78 bit the big one was due to the fact that the commercial receivers/transceivers of that time did not have "hot" receive capabilities, like today's rigs do. I recall having two Hammarlunds and a Hallicrafters during those years. I believe I worked a total of five DX stations on ten and fifteen during that peak.
If I could take one of the Icom's, Yaesu's or Kenwood's of today back into that era, I'd probably would work a ton of DX.
73, Bill - WA8MEA
http://HamRadioFun.com
|
| |
|
RE: RF Field Changes
|
|
|
by WX4O on October 16, 2005
|
Mail this to a friend!
|
I was stationed in W. Germany in 78,79,and 80 and worked tons of DX with my 4BTV roof mounted (4th floor of my quarters and with indoor radials in the attic). Worked all US states but 3. I was using a TS-520 then, not a souped up rig. Wish I'd never sold it.
|
| |
|
RF Field Changes
|
|
|
by K0COS on October 16, 2005
|
Mail this to a friend!
|
I know what the problem is. It is the 53rd harmonic of "Ivan the Woodpecker" reflecting back to earth from a galaxy far, far away!
Michele - K0COS
|
| |
|
RE: RF Field Changes
|
|
|
by NN6EE on October 16, 2005
|
Mail this to a friend!
|
WX4O,
Why lament about the lose of your TS-520 after being stationed in W. Germany???
It was'nt the rig nor the antenna that garnered you all of those great contacts, IT WAS YOUR LOCATION!!!
You could've worked the STATES with a "Wet-Noodle" and 1 watt!!!
:-)))
Jim/ee
|
| |
|
RE: RF Field Changes
|
|
|
by WA5MKA on October 16, 2005
|
Mail this to a friend!
|
1979 & 1980 were very good propagation years ! 100 countries & 50 states from north central Tennessee on 10 meters using a Kenwood TS-520S barefoot to an 8 ft. ground mounted vertical with 4 quarter wave radials. The sporadic-E was great in the summers of those years !
On another note: has anyone else heard the strange pulsing noise that comes & goes on 40 meters this year (didn't hear this noise last year) ? It seems to travel up & down the band also. It can appear on the band day or night. Sometime it is stronger in the daytime. The noise blanker in my rig will not knock it down, although the blanker will knock down local line noise from S-9 to S-4. At times it will wipe out the whole band from approx. 7.265 Mhz & below, except for super strong signals(S-9+).
Also there is another weird noise that can appear out of the blue & can wipe out a 20 to 25 Kc wide section of the band but has no carrier, so it appears not to be Foreign Broadcast, unless it is that DRM (Digital Radio Monodial) the Broadcasters are experimenting with ! Has anyone else heard this noise ? It wiped out the other station I was in QSO with just a couple of nights ago. I haven't heard it before on the band until this year.
73 & thanks,
George---W7KCU, ex: WA5MKA
|
| |
|
RE: RF Field Changes
|
|
|
by K4JSR on October 16, 2005
|
Mail this to a friend!
|
Vito said, "I noticed that the Republican and the Democrat radios have most of the noise, but not so on the independent radios, the independent radios are at a zero noise level."
That is because the independents have better sense than to say anything at the moment!
Actually all of the noise started when they put those footprints all over the moon!
I know that the last time I mooned someone I got a footprint! Butt that is another story!
|
| |
|
RE: RF Field Changes
|
|
|
by WA6BFH on October 16, 2005
|
Mail this to a friend!
|
It seems that a certain contingent of independents (Libertarians) seem to be cozy’ing up to the far out DNC. I don’t understand that at all. Its not what I would call the Libertarian philosophy.
Oh, and we need more footprints on the Moon.
Actually tread-marks from rovers like the ones we have on Mars would be best!
|
| |
|
RE: RF Field Changes
|
|
|
by W9WHE-II on October 17, 2005
|
Mail this to a friend!
|
Didn't John Kerry have a plan for this?
Fear not, as AA4PB wrote, President Bush will turn propigation back on after ham radio's abillity to save millions of lives has passed.
W9WHE
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 17, 2005
|
Mail this to a friend!
|
On another note: has anyone else heard the strange pulsing noise that comes & goes on 40 meters this year.
----
George, I think this might be Over the Horizon Radar used by the military. We used to call it the "Russian Woddpecker"
Not sure why it's been parked lately on 40m band tho..
73
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 17, 2005
|
Mail this to a friend!
|
Interesting NASA article about recent sun/solar activity.
"sunspot numbers have declined since 2000, yet solar activity persists. How can this be?"
Source:
http://science.nasa.gov/headlines/y2005/15sep_solarminexplodes.htm?list68614
|
| |
|
RF Field Changes
|
|
|
by KE4ZHN on October 17, 2005
|
Mail this to a friend!
|
|
Im surprised that nobody mentioned space aliens being responsible for this! Little green guys orbiting earth in a stealth ship flipping switches and messing with our atmosphere to test our reactions. Or perhaps its all those cow farts that the scientists said were damaging the ozone layer? All that methane cant be good for the atmosphere. It sure isnt good for our noses if we happen to be around a cow that lets one go! Then again it could be all the hot air generated by the crooks...I mean politicians up in Washington DC. With all the BS and hot air coming from there it has to be damaging to the atmosphere! Its usually devastating to our wallets everytime they open their traps. Maybe its a combination of all of the above? You hear that? Its the Twilight Zone theme playing softly in the background.
|
| |
|
RF Field Changes
|
|
|
by G6XCJ on October 17, 2005
|
Mail this to a friend!
|
|
My concern has been aroused too, in that our local uhf repeater gb3ny despite quite hilly topography can be accessed from 25 miles away on 5w but only if one is near to power lines? I am investigating and carefully logging all my mobile working outside of a 25 mile perimeter and have found that providing i am within 100yds of overhead power lines i can access the repeater easily, but why is this?
|
| |
|
RE: RF Field Changes
|
|
|
by N0TONE on October 17, 2005
|
Mail this to a friend!
|
|
Power lines are usually situated in easily-accessed rights of way, with much RF-absorbing foliage removed. No mystery.
|
| |
|
RE: RF Field Changes
|
|
|
by K3WVU on October 18, 2005
|
Mail this to a friend!
|
|
I've been involved with radio communications (the mid-60's) and I have noticed a change in the noise level on HF. I've always put it down to an increase in the level of manmade noise from RF devices and powerlines. As Alan, K0BG, pointed out above, our collecttive experience with RF only goes back 100 years or so, and there could be cyclical events of which we know nothing that could be affecting things. Of course, it's all subjective, unless someone, somewhere, has been measuring it.
|
| |
|
RE: RF Field Changes
|
|
|
by AA4PB on October 18, 2005
|
Mail this to a friend!
|
Maybe if the noise level continues to rise, BPL won't function either. Then what will we do?
|
| |
|
RE: RF Field Changes
|
|
|
by W9WHE-II on October 18, 2005
|
Mail this to a friend!
|
Don't worry, if BPL does not work, Haliburton's BGPL (Broadband over Gas Pipelines) will. Plus, as an added bonus, 10% of the revenues from Haliburtion's BGPL products will fund the FBPI (Federal Bureau of Privacy Invasion) that will track your internet activity!
W9WHE
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 18, 2005
|
Mail this to a friend!
|
Of course, it's all subjective, unless someone, somewhere, has been measuring it.
---
That's an interesting point. For example how many computers exist that generate radio noise today in comparision to say, oh... the year 1990.
Rank Country Number of computers (2005)
1 United States 164,100,000
2 Japan 49,900,000
3 Germany 30,600,000
4 United Kingdom 26,000,000
5 France 21,800,000
6 Italy 17,500,000
7 Canada 16,000,000
8 China 15,900,000
9 Australia 10,600,000
- South Korea 10,600,000
1990 Timeline:
World Wide Web described by Tim Berners-Lee
Electronic Frontier Foundation founded
First palmtop computers
First commercial provider of dial-up net access
99% of US households have at least one radio
Hmmm. Could be a connection here...
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 18, 2005
|
Mail this to a friend!
|
1988 Timeline
"4.7 million microcomputers, 120,000 minicomputers and 11,500 mainframes sold in US"
|
| |
|
RF Field Changes
|
|
|
by KN4LF on October 18, 2005
|
Mail this to a friend!
|
Man induced harmful global warming is a lie. Global temperature has fallen by 0.5 deg. F since 1905, 1 deg. F in Florida.
The ozone hole is a naturally occurring event tied to annual changes in wind shear in the Stratosphere. It's always been there and is not expanding due to man made CFC's.
I worked for Uncle Sam doing space & atmospheric weather research and forecasting during the "Cold War" era. Neither the ex U.S.S.R. or U.S. governments ever developed successful weather modification weapons.
It's just another urban legend, ignorant and paranoid conspiracy theory.
And no we are not changing the ionosphere either.
73,
Thomas Giella, KN4LF
Retired Meteorologist, Plaeoclimatologist & Space Plasma Physicist
Lakeland, FL, USA
http://www.kn4lf.com/kn4lf42.htm
|
| |
|
RE: RF Field Changes
|
|
|
by NI0C on October 19, 2005
|
Mail this to a friend!
|
KN4LF says:
"Man induced harmful global warming is a lie."
"The ozone hole is a naturally occurring event tied to annual changes in wind shear in the Stratosphere. It's always been there and is not expanding due to man made CFC's."
These assertions are mere wishful thinking. The Bush Administration has been willfully interfering with studies of global warming. They are not interested in the truth.
I'd rather discuss the performance of your K9AY loops with you.
73,
Chuck NI0C
|
| |
|
RE: RF Field Changes
|
|
|
by KC8VWM on October 19, 2005
|
Mail this to a friend!
|
Neither the ex U.S.S.R. or U.S. governments ever developed successful weather modification weapons.
It's just another urban legend, ignorant and paranoid conspiracy theory.
So are you saying they never tried?
|
| |
|
RE: RF Field Changes are Bush's fault
|
|
|
by W6DLF on October 20, 2005
|
Mail this to a friend!
|
Hey, let's not be blaming our president. These things are caused by the turning of the Axles of Evil...
Pray for propagation!
|
| |
|
RF Field Changes
|
|
|
by KG4RRN on October 21, 2005
|
Mail this to a friend!
|
I think that the RFI on HF has been going on a cycle--much like the rotation of the earth and sunspots, they come and go in cycles-remember when six-meters was open?
I rememeber that when Katrina hit New Orleans, I was able to tune a copper pipe and connect that to a shortwave reciever to hear a NCS in "Oregon"?
But that is just me, see, I live on a hill.
A lot of hams dont have that luxury.
On the other argument regarding the static bursts between 6-9PM-- I have experienced that first hand.
But the only problem is when I try to talk on a repeater 100 miles away, it is not usually a problem locally.
More people = more electrical use= more RFI ....
Bob Rice, KG4RRN
|
| |
|
RE: RF Field Changes
|
|
|
by KG4RRN on October 21, 2005
|
Mail this to a friend!
|
"Sensors on full Mr. Spock"
Capt. Kirk- Captain of the U.S.S. Enterprise
Galaxy Class Starship
Thanks for the scientific explaination of antennas are really sensors....haha... oh please... stop it.....
|
| |
|
RE: RF Field Changes
|
|
|
by W9WHE-II on October 24, 2005
|
Mail this to a friend!
|
N1OC writes:
"The Bush Administration has been willfully interfering with studies of global warming. They are not interested in the truth"
Bush, Cheny and Halliburton are banking on profits from global warming! If the atmosphere warms 20 degrees next year, as so many global warming scientists predict, then you will be drawing a lot more electricity to run your air conditioners. And you know who benifits?
BUSH, CHENY and HALLIBURTON!
Its all part of the vast right-winged conspiracy!
W9WHE
Card carrying member!
|
| |
|
RE: RF Field Changes
|
|
|
by W9WHE-II on October 24, 2005
|
Mail this to a friend!
|
KC8VWM writes:
"Neither the ex U.S.S.R. or U.S. governments ever developed successful weather modification weapons.
It's just another urban legend, ignorant and paranoid conspiracy theory"
Ha! That's what you think.
If the US never developed a successful wheather modification system, just how did Bush & Cheny steer Katrina away from rich, white, Republican Corpus Christie and into poor, Black, Democratic New Orleans?
After all, everybody knows that New orleans was Bush's fault. And, what about that earthquake in Pakastan....I bet you never heard of the top-secret earth bending weapon, now did you?
W9WHE
|
| |
|
RE: RF Field Changes
|
|
|
by N8CPA on October 25, 2005
|
Mail this to a friend!
|
|
I don't think propagation has changed. Noone has repealed the laws of physics. What has changed over the last 30 year or so, is the number of incidental radiators. The cumulative effect is broadband. Our receiver front ends are preloaded with the stuff.
|
| |
|
RE: RF Field Changes
|
|
|
by W2EV on October 29, 2005
|
Mail this to a friend!
|
What has changed is the number and variety of active radiators. The physics hasn't changed, our activity has.
Want to prove that? Visit this website (http://www.PropNET.org), download the software and power-up. You will quickly see that the laws of physics have remained unchanged.
Ev, W2EV
|
| |
|
RF Field Changes
|
|
|
by W8QP on October 30, 2005
|
Mail this to a friend!
|
You may be correct but don'tforget that 25 years in the over all scheme of things is a very short period of time. Maybe what we experienced many years ago was a fluke and what we are experiencing now is normal
In relation to the weather please consider this. We live in a dynamic world and the earth well either get warmer or colder but it will not stay the same.
Bill W8QP
|
| |
|
RE: RF Field Changes
|
|
|
by W9WHE-II on November 2, 2005
|
Mail this to a friend!
|
Global warming is the cause and its all Bush, Cheney and Halliburton's fault!
If Bush & Cheney hadn't taken us to war so Halliburton could make Billions on Iraqi oil, and they weren't in collusion with automakers to make gas guzzeling SUVs, we would not be faced with a 100 degree per year global warming rate, which drives up demand for Haliburton's oil to run air conditioners and destroys the Ionosphere.
Bush & Cheney have a plan to replace ham radio with a $$$ fee for QSO program, run by Halliburton. Soon, Bush, Cheney and Halliburton will charge you for each QSO, which you will ONLY be able to make over BGPL (Broadband over Gas Pipeline) run exclusively by Halliburton!
W9WHE
|
| |
|
RE: RF Field Changes and More Thoughts
|
|
|
by PETEMILLIS on November 3, 2005
|
Mail this to a friend!
|
In response to Tim....
I would just like to say that I am doing my bit for the population. My wife and I have 4 children. Now some may say that is not on, but there is a very realy problem in some countries with population decline. Yep we need some decline and this is mainly coming about through an increasing number of same-sex couples, or career couples, who won't be wanting kids (the same-sex couples point made by Tim is very interesting - this is something that has been observed in fish where the population grows out of control, food runs short, and all the male fish start loving each other).
Anyway, we have 4 kids - my wife's 3 brothers and 2 sisters have 4 kids between them, my 2 sisters and 1 brother have NO kids between them. So when we average it out, there are 8 kids between 10 people - so not even enough to replace us 10 when we die.
I've now had the snip.
As for unusual band noises - my main problem is my next door neighbour's electric wheel chair charger that he plugs into in the evenings. Totally obliterates 17, 15 and 12 metres with massive broadband hash. Perhaps the proliferation of electric wheelchairs and motorised mobility scooters over recent years is partly to blame for increased after dark noise levels.
the idea is that when they've grown up we can move them to parts of the world where the population needs bolstering.
|
| |
|
Email Subscription
You are not subscribed to discussions on this article.
Subscribe!
My Subscriptions
Subscriptions Help
Other Recent Articles
Student Sends MIT Letter to Space:
Amateur Radio Club Talks to Hams Worldwide on Centennial:
New Communication Exhibit Helps Kids Get the Message:
Transmission of Images - No Internet, Satellite, Cable, or Cells Needed!
Deltona Youth Loves to Ham It Up on the Radio:
|
