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eHam Forums / Misc / RE: How much CB is still out there?
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on: November 17, 2012, 05:33:05 PM
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AXW; I agree with you 100%! But in my twelve years as an occasional eham thread reader, it seems like whenever someone brings up CB, they get blasted. Now, I'll admit, I haven't had a CB in twenty years, but last week the UPS man delivered the aforementioned Uniden 980SSB and a Browning NMO 11 meter antenna and magnetic mount. I put it on my truck and have been monitoring the band on my way to and from school. I've actually had a few lengthy civilized conversations on it. It seems the CB equivalent of CQ is to call for a radio check. I've answered quite a few of these with a 'sounds good here on blah blah highway near exit so and so, what's your 20?' and a nice conversation has always followed. Right now it's just sitting in the passenger seat but I might have to go ahead and mount it somewhere! Or at least put it in the shack next to the 7600.
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eHam Forums / Misc / RE: How much CB is still out there?
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on: October 30, 2012, 08:45:28 PM
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Dang! I clicked on this link to see how many people flamed this guy for asking for opinions on installing a CB! What I saw was a couple dozen legitimate arguments FOR installing it. Hell, I'm sold!! I want a CB now! In the 80's I was way too young to drive but I had a Cobra 142 GTL base station in my bedroom and there was a lot of local CB traffic in my town, it was a blast getting on there at night and talking / listening to the people cruising main street. There were several other kids around town that would "hang out" on "our" channel and do "fox hunts" (more like Marco-Polo on the air) Plus, working a foreign station on SSB was a real thrill, Hell, working someone in the next town was a thrill now that I think about it. I agree with all of you, I'm tired of spending money on VHF/UHF gear just to have it sit in my truck and every once in a while give a repeater ID. looking on Amazon, Uniden has a new one with a color display, SSB and weather band for $150. http://www.amazon.com/Uniden-BEARCAT-980SSB-Sideband-WeatherBand/dp/B007B5ZAES/ref=sr_1_1?s=electronics&ie=UTF8&qid=1351654521&sr=1-1&keywords=uniden+ssb
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eHam Forums / Elmers / RE: End fed transmitting antenna with 9:1 UnUn.
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on: August 11, 2011, 07:03:03 AM
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Thank you everyone for your replies! I'm familiar with beverage antennas and balanced feeders, I've never had an antenna with traps. This could work, I could Put up an 80 meter 1/4w with a trap for 40 and 20. and feed it against the metal roof of the building.
Somebody mentioned the all mighty fan dipole.. I can't center feed this antenna but maybe I could put up a fan.... uni-pole fed against the roof, something like an alpha delta DX-CC cut in half.
I've still got the UnUn coming in the mail so while I'm waiting for the traps to arrive, I may try the 124 foot wire and just sweep it and report my results.
Thanks again.
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eHam Forums / Elmers / End fed transmitting antenna with 9:1 UnUn.
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on: August 10, 2011, 07:31:37 AM
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I have a question regarding the use of a 9:1 UnUn. I've searched the forums and maybe I missed it but I didn't find anything relating to my application. I need to erect an end fed wire antenna for a temporary (a few months) application. I can put up a 100+ foot sloping wire with a feed point height of about 18 feet at the roof peak and end point height of about 60 feet in a nearby tree. I must use coax (unfortunately) as the feedline. (the roof is metal so this could be used as a ground plane) The coax will be 20 foot of RG8X and if a transmatch is needed at the rig end, I have an MFJ-901B. (Rig is an IC-7000) I would like to have multiband capability so I found this 9:1 UnUn at balundesigns.com http://www.balundesigns.com/servlet/the-102/QRP-9-cln-1-Unun-1.5/DetailHe lists recommended wire lengths in this document: http://www.balundesigns.com/Wire%20Length%20for%209132s.pdfYou can see the magic numbers of 52.5 or 124 feet show an SWR of well under 2:1 on ALL bands. I plan to use 124 feet for my antenna. It's seems this type of antenna is only ever used for receiving, but this UnUn is rated at 300 watts and he makes a 2KW version! My question is simply, what's the catch? Why is this not a widely used multi band antenna? An end fed wire with a ~1.5:1 SWR on all bands, no traps, no resistors, just a simple matching transformer?? It seems too good to be true and I'm sure you guys will confirm my suspicion but I have to try it. If this doesn't work as advertised I'll install my AH-4 coupler but I was really hoping I wouldn't have to (I use it for portable ops so it's currently mounted to a spiderbeam mast) Thanks in advance! Larry AD5VM.
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eHam Forums / QRP / RE: What is your ideal PORTABLE QRPp antenna?
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on: May 20, 2011, 01:06:37 PM
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Ok, I haven't read all the posts but here's my .002.
I am primarily a portable op. I've had the MP-1, buddipole, buddystick, hamstick dipoles, MFJ-apartment antenna, B&W AP-10A, Miracle antenna, MFJ-18XX loaded telescopic whips, MFJ-933 portable magnetic loop tuner and homebrew versions of pretty much all of those. I've also done the remote-base thing with full size mosley tribanders on 30 foot masts, Traffie Hex-beams all band doublets and full size dipoles and once i spent two days at my campsite at 10,500 feet on the top of mt Withington, NM installing a full size 160 meter loop at no less than 45 feet high in the tree tops and fed it with ladderline to a Palstar BT-1500A balanced tuner.... I like operating out of doors... a lot... and I'm also not a CW guy.. Not because I don't know code, I'm currently #284 on the RufZXP high speed CW toplist. But almost all of my operating is SSB.. Which puts me at even more of a disadvantage when running low power with compromise antennas. Currently I'm building a Super homebrew buddipole. Using two of the long spreader arms, a homebrew coil on 3" PVC with a tap for 40 and 75 meters and an MFJ-1979 16.5 foot stainless steel collapsible whip. If you don't have an MFJ-1979 yet... Order one. Once the word gets out about this new product, they will be backordered for months. I've also got a ZM-2 tuner and a bunch of precut wires.
All of those antennas preform exactly as you would expect..
-The micriacle antenna and MFJ loaded whips work ok on receive only. -The B&W AP-10A, hamsticks and hamstick dipoles, buddistick, Apartment antenna will make a few contacts but I found that even though I "worked just about everyone I heard" the signal reports were lousy and and I found myself shouting into the mic and had to repeat everything I said. -The Magnetic loop tuner actually worked quite well, I sold it but wish I hadn't. I used 1/4" ice maker tubing as the elements but you need one for each band cut to something like 1/10th wavelength. And that is a lot to carry in a backpack. -The full size buddipole with 10 foot whips on a 16 foot mast/tripod is also a pretty good performer if you don't mind leaving everything else out of your pack... -The ZM-2 and a bunch of pre-cut wires is a great combo.. Hard to beat, I have an 80 meter loop fed with cheapo 300 ohm twinlead that works well on all bands. -My favorite remote base antenna is my 40 foot spiderbeam mast with an Icom AH-4 clamped directly to the base. I use a 43 foot wire very loosly coiled all the way up the mast and I have twelve 15 foot radials each with an aligator clip on both ends. I have a six inch piece of ground braid hanging off the ground lug of the AH-4 so I just clip one end of each radial to the braid and the other end to a stick or weed to keep them straight. This works well with my IC-7000.
The best portable antenna in the world is the Par end fedz series. I have an EF-20 an EF-40 and an EF-10/20/40. The EF 10/20/40 will work with any half wave wire 5MHz through 30MHz. I either throw a line over a tree limb or bring my spiderbeam 40 foot mast if I can drive there. The EF-20 and the MFJ-9420 SSB adventure radio and a 5Ah gell cell battery will have DX stations scratching their heads when you tell them you're QRP portable...
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eHam Forums / Elmers / HamGadgets.com
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on: August 02, 2009, 04:15:30 PM
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the pico keyer is incredibly easy to build and use and modify for your application.
I've built probably six of them and put them in all manner of QRP rigs. Sometimes I use the included battery, others I hardwired the power to come from the rig, it comes with instructions and the couple extra parts to do this. You can use the included piezzo buzzer for sidetone or configure it to inject it into the audio stage of the radio.
Can't go wrong.
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eHam Forums / Elmers / HF Antenna for confined space
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on: May 26, 2008, 09:19:45 PM
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Okay, I read your post again, I see the space is horizontal. Really the biggest problem with the apartment balcony is 1)RF shielding from all the rebar, stucco (wire mesh) etc... and then RFI from all the people and their electronics. If you could get a tiny 26ga copper-clad steel wire strung from their balcony to a nearby tree and then use the SGC coupler/radials mounted in the balcony, I think that would be the best bet. All bands, one touch tune, and decent performance with good ground and radials. Even if all you can get is 23ft of wire in the clear, it should tune all bands from 160-10 meters. http://www.thewireman.com/antennap.html(scroll down to item#534) http://www.universal-radio.com/catalog/hamtune/1238.html
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eHam Forums / Elmers / HF Antenna for confined space
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on: May 26, 2008, 09:09:05 PM
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Well, not a whole lot you can do here. 30ft long is enough to put up a great 20 meter antenna. The Par Electronics EndFedz dipole: http://www.universal-radio.com/catalog/hamwire/4456.html It's 33ft long and is fed on the end. That's assuming your space is horizontal. If the space is vertical, then you're golden, just slap up a Hustler 5BTV for $150: http://www.dxengineering.com/Products.asp?ID=141&SecID=16&DeptID=8 cut a single counterpoise 1/4 wavelength long for each of the five bands and run them around the floor of the balcony and also attatch the ground to the metal railing. Another alternative would be using a 30 foot long wire connected to an auto antenna coupler like these: (for any radio) http://www.universal-radio.com/catalog/hamtune/1238.html(for newer Yaesu rigs) http://www.universal-radio.com/catalog/hamtune/0643.html(for most Icom rigs) http://www.universal-radio.com/catalog/hamtune/3702.htmlAnd then yet another option which is great for 10/12/15/17/20 meters is the following: http://www.twantennas.com/I'm thinking if cost were not a big factor, I'd go with the TW antenna sitting on the ledge, and then I would also use a coupler/30 foot wire, if you connect a few radials and the metal railing to the ground side of the coupler (the coupler will go outside and connect directly to the longwire) then they should be able to use it on 80-10. If cost is a big factor, I'd just try the coupler by itself. Both the TW and the auto coupler would be a good choice for blind hams, with the TW you just push one of five buttons to change bands and with the coupler, you just push the tune button on the rig. I don't think an MP-1 or a Buddi-Pole would be good because they would have to change taps or move coils to change bands. Also a motorized screwdriver would require them to be able to see the SWR meter for best tuning but that may be worth looking into, again with the screwdriver it would require a radial for each band and a good ground connection. Tarheel makes some good ones: http://www.tarheelantennas.com/mobile_antennasAnd the last option I can think of for a person in this situation is a remotely tuned magnetic loop. MFJ makes one that gets good reviews: http://www.mfjenterprises.com/Product.php?productid=MFJ-1788The problem with the tuned loop is that it would make it kind of hard to tune without being able to see the SWR meter. But it would be much easier than a screwdriver because the Q is so high that the antenna is totally deaf until it comes into resonance at the operating frequency so when the band comes alive, it's close to tuned. But I would still look at the TW or the coupler ideas first. Good luck! 73 Larry
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eHam Forums / Elmers / grrr noise...
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on: March 07, 2008, 05:27:00 PM
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I once read an article about a guy who had the same problem. Turned out to be a doorbell power supply in a house like two blocks away! He tracked it down with a portable SW radio.
You could build a small loop antenna with some magnet wire and a pizza box.
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eHam Forums / Elmers / grrr noise...
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on: March 07, 2008, 05:20:39 PM
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I had a 'grr' noise also, it turned out to be a touch lamp in the next room. It made the noise even if it was turned off! At my previous QTH I had a problem with power line noise and the MFJ-1026 would bring it from an S9 to about an S1 but like a previous post said, it didnt happen right out of the box. The sense antenna has to hear the same exact noise so if you have a 5 element quad pointed right at the power substation across the street, then you'll probably need a second 5 element quad as the 'sense' antenna hihi. I was able to use a small six meter dipole that I put up near my main antenna (pointed in the same direction) and that worked just fine but it's not magic. Just phase inversion. If you have a big pile of money, you could get the DX engineering version which may be better: http://www.dxengineering.com/Products.asp?ID={6F07CEB4-27D0-4664-A2AA-352A69ED88CD}&SecID=114&DeptID=12
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eHam Forums / Elmers / Reported RF.......What to do?
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on: February 19, 2008, 04:14:08 AM
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I have the same radio and the Heil PR20 mic (very similar element) If you have the processor turned on, turn it off or at least keep it down below 9:00.
Ensure you have a good station earth ground.
Use a choke balun at the antenna feedpoint.
Use a second receiver to listen to your signal and connect a dummy load at the antenna feedpoint to eliminate the antenna, then at the output of your tuner to eliminate your feedline, then at the output of your amp to eliminate the tuner, then at the rig to eliminate the amp!
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eHam Forums / Elmers / HF antenna choices for apartment
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on: February 19, 2008, 03:56:43 AM
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I almost forgot, I bought and used one of these on a 6 week business trip. http://mfjenterprises.com/Product.php?productid=MFJ-935BI bought a roll of 1/4" copper tubing (the kind connected to your ice maker) I cut a length for each band (75% of 1/4 wavelength ie: 12.5ft for 20 meters) and made tons of contacts with that thing just sitting on the coffee table in the hotel room! Some good DX when the bands were open. One thing you need to be aware of is the high current that exists on a tuned loop like this when you are transmitting. I was using a TenTec Argo V with 20 watts output. Oh yeah... Use CW or PSK31! That will increase your chances tenfold!
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