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1  eHam Forums / Satellites / RE: Will they update SAT status on Amsat.org? on: Yesterday at 06:33:10 PM
Appreciate the comments, and the link to the UK version of amsat.  To KO4MA, Your two "thoughts" make my point clear.  Launching satellites and maintaining interest in satellite operations costs money, and a useful and attractive Website on the "flagship website" would probably go a long way to attracting some of the many new amateur operators entering the hobby.  I have donated to the launch funds, but a proper attention to the site would attract new membership.  If we acknowledge where the work needs to be done, we can do it.  Can anyone here look at the currant Amsat NA site and state that they think we are going to attract the membership and funding to get more satellites  launched?  I don't think so...  I know it is a great deal of work to make a quality website, but if you are trying to obtain hundreds of thousands of dollars in funding, (just like grant writing) you show a "polished" finished proposal.  the Amsat page is the "face" we show to new hobbyists AND potential donors.   
To reiterate: 
-If you are an IT security expert, donate your time
-If you are not:  Send Cash!

Yes, the new site is sparse.  The problem is that the old site was cobbled together over years and fell to hackers because it was not built to modern security standards.

Most of the old satellite information pages are available from the WayBack Machine, using your search engine.

'Satellite Status" IS available at the AMSAT site using User Reports.  A different format than we are used to, but perhaps more timely than the old page.

Cheers, bill  (Fox-1 contributor)
2  eHam Forums / Mods And Repairs / RE: Wouxun KGUV6D V2 HT Flashlight LED Voltage? on: Yesterday at 06:09:03 PM
-You are using a $40 radio as if it was a $5 flashlight.

-After burning out two radios it is clear that your usage is beyond that expected by the designers, and therefore inappropriate.

Solution:  Buy a flashlight, and promise not to use it as a radio!

-The manufacturer has bent over backwards to acommodate you, but don't be surprised when they refuse further repairs/exchanges.
3  eHam Forums / Misc / RE: The "D-Star" Tizzy on: Yesterday at 05:46:36 PM
Starting a thread to discuss a thread on another forum.  Brilliant and pointless.  sheesh.
4  eHam Forums / Misc / RE: All the billionaries are investing in empty boxes..hurry before the bubble burst on: May 18, 2013, 03:36:41 PM
I don't find the idea absurd.  Collectors collect things.  Tube collectors collect tubes as well as tube boxes.   The value of anything is what a will buyer will pay a willing seller.
5  eHam Forums / Elmers / RE: RST confusion..inexperienced needs Elmer... on: May 15, 2013, 04:17:45 PM
http://www.antiquewireless.org/1929transmitters.htm

Here is a link to a page with some off-air recordings of early type transmitters. 

You can hear examples that range from a T1 broad AC, T3 rough with some filtering, to an unstable 'Yoopy' oscillator, and one that starts raspy, maybe T5, an becomes more stable as the QSO goes on.

This subject deserves some attention to developing a video of examples for training. 

Someday, oh well.  Smiley   bill
6  eHam Forums / Antennas and Towers and more / RE: 20m "random" wire length? on: May 13, 2013, 07:53:04 PM
As long as you your tuner can match the load, that is all that matters.

When the tuner "matches the load", the antenna system is resonant by IEEE definition. The random length of wire winds up being one component in a resonant antenna system just as the caps and coils in the tuner are components in the resonant antenna system. Such can be proven by using a grid dip meter on the random length of antenna wire after the tuner is properly adjusted. Assuming the receiver has a 50 ohm input impedance, the GDO will indicate a resonant dip very close to the transmitter frequency after the tuner has achieved a match.

http://www.w5dxp.com/OWT1.htm
A wonderful discussion of antenna matching.  I don't believe anything I have said disagrees!  Cheers, bill
7  eHam Forums / Antennas and Towers and more / RE: 20m "random" wire length? on: May 13, 2013, 07:47:20 PM
KB4QAA,

I think the point of the web page cited by K3ANG is that there are certain lengths that a "random" wire will be easier to match.  Many of the tuners/couplers in use have difficulty matching a "random" wire that is very close to a half wavelength at the desired frequency.  Some lengths manage to avoid that situation on all bands, and therefore the reason for such web pages.  The antenna works "better", simply because it can be matched with commonly available tuners/couplers.

73 de wb0ksl
John

Sir, I absolutely agree with that that the thought behind the recommendation is to make matching easier.   But the myth that is propagated is that 'random' antennas can/should be cut for specific lengths for better performance. This is untrue.  If we choose to cut an antenna for a particular length (for easier matching, i.e. lower impedance) then it is no longer a random wire antenna.  

Further, the while matching may be easier, the antenna performance does not change.
8  eHam Forums / Antennas and Towers and more / RE: 20m "random" wire length? on: May 13, 2013, 12:50:07 AM
Lengths that work, and don't work, for random wire antennas.
http://www.hamuniverse.com/randomwireantennalengths.html
de K3ANG
Pure urban myths!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Any piece of wire will radiate.  There are no magical lengths.

The purpose of a 'random wire' antenna is putting up whatever is convenient or possible, not putting a tuned antenna.

As long as you your tuner can match the load, that is all that matters.
9  eHam Forums / Mobile Ham / RE: To modify or not to modify my existing antenna system That is the question! on: May 08, 2013, 01:41:59 PM
Quote
And is why I stated a 50 ohm Non inductive surge impedance as driven at the antenna expressed as a 50 ohm Rr.

Surge Impedance?  We aren't dealing with HV power transmission lines.
10  eHam Forums / Antennas and Towers and more / RE: Hy-Power Dipole way out of band on: May 04, 2013, 08:30:28 PM
Forget their numbers.  That is for the antenna hung in ideal outside conditions.

You can only do one thing at a time.  We must start with the "inside" portion of the antenna, 20 meters.

(resonant F - Desired F) / resonant F  = Delta of Freq (in Percent) needed to change

Percent * antenna length = Amount to trim/add

So...

13.538 Mhz - 14.285 Mhz = 0.747 Mhz
0.747 / 13.538 = 0.0552  or 5.52% "too long"

17'10" (leg) *2 = 35.66ft (Present length)
35.66ft * 0.0552 = 1.97ft  to shorten 20m antenna
1.97ft /2 = 0.98ft * 12" = 11.8" to shorten each side.

-I recommend not cutting the wire, just wrap around main wire until you sure of the length.  You may have to adjust once or twice more.
-Keep the whole antenna intact, re-hang it and make measurements again.

40m will be done the same way.    bill

This method will work for essentially any antenna assuming the adjustments are linear.  It can save a ton of walking back and forth.
11  eHam Forums / Boat Anchors / RE: RESTORED SBE MODEL 33 HF RIG on: May 04, 2013, 03:32:34 PM
Very nice job Dale!   The counter looks fabulous.  Seems the  Cumbria Designs huff n puff stabilizers are becoming popular.

Thanks for sharing your work. The website is super.  Bill
12  eHam Forums / Antennas and Towers and more / RE: My house / Aluminium siding on: May 04, 2013, 03:26:24 PM
Go count how many panels need to be bonded (don't forget all four sides).

Any poorly bonded joint can become a semiconductor and cause RFI. 
13  eHam Forums / Antennas and Towers and more / RE: ICE Anti-Oxidants on: May 04, 2013, 03:18:35 PM
http://www.morganmfg.us/radio-products/conductive-anti-oxidant-compounds/

Morgan Manufacturing is owned by a relative of the ICE owner.  This fellow did most of the manufacturing for ICE.  He has many of the same products.  Unfortunately he has not done a good job of advertising his connection and products. 

I have no experience with MM, so can't vouch for him.  bill
14  eHam Forums / Mobile Ham / RE: To modify or not to modify my existing antenna system That is the question! on: May 03, 2013, 09:33:11 PM
http://www.k0bg.com/caphats.html

Yes, capacity hats will definitely improve the efficiency and performance of shortened antennas like mobile antennas.

They work by distributing the RF current more evenly across the antenna.  And RF current is what creates our EM field.

They should be placed at the END of antennas.

They should be placed as far away from loading coils as possible.

You will need to retune the antenna after adding a cap hat.

See Alans website above for more info.

p.s.  "Hot Rodz" Capacity Hats are sold by DX Engineering.
15  eHam Forums / CW / RE: Value of rare Datong CW keyboard? on: May 03, 2013, 09:14:46 PM
My wild guess is $30 absolute tops, unless there is someone that is a Datong fan.
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