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October 17, 2018, 03:09:22 PM *
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 on: October 13, 2018, 04:14:41 PM 
Started by ka1tdq - Last post by W1RKW
concur with Lou.

Nice looking kids, John.

 on: October 13, 2018, 01:30:32 PM 
Started by ka1tdq - Last post by ka1tdq
Ok, it's done. Now I just need to test it.


 on: October 13, 2018, 09:13:17 AM 
Started by ka1tdq - Last post by ka1tdq
Maybe waiting can be a good thing. I found a nice piece of stainless steel at the junkyard that will fit all the parts nicely. It'll keep with my current theme of open frame construction.


 on: October 12, 2018, 06:47:15 PM 
Started by ka1tdq - Last post by Lou W9LRS
Not Cheesy...Proud PAPA.

 on: October 12, 2018, 06:45:03 PM 
Started by PA0NVD - Last post by PA0NVD
Here a few pics of the noise canceler
Don't be scared for the rubbish below the little trim pot, it all shouldn't be there. It is a small 15 dB amplifier to test if I can amplify the noise a little more because my noise pick-up antenna was very small. Now I have a 2 1/2 whip and the gain of this circuit was lowered to a few dB only and can be missed.
I like to try a very small active whip antenna from PA0RDT because I noticed that there are many resonances and the phase / amplitude of the noise antenna changes very much when one tune to an other frequency. This because the simple whip antenna is a very bad match to the cable and one like a noise antenna that works for all bands.  The PA0RDT mniwhip is wideband from longwave to 30 MHz and is a good match to the cable. The SDR receiver in the Netherlands from the Twente university uses this antenna
The info for the miniwhip can be found googeling - PA0RDT miniwhip antenna -
Attached the diagram

 on: October 12, 2018, 06:29:05 PM 
Started by KZ5A - Last post by KZ5A
The title says it all.  I need one with good cosmetics but functionality of the meter movement is not required.


73 Jack KZ5A

 on: October 12, 2018, 03:48:48 PM 
Started by kw7y - Last post by w3khg
Willing to work anyone on 20 meters either on .286 or .330 anytime.

Liberty, NC

 on: October 12, 2018, 03:26:07 PM 
Started by PA0NVD - Last post by PA0NVD
Hi Bob
It was nice to talk to you over the radio!! I hope we meet again and in future with AM
I will make some pics and post.

 on: October 12, 2018, 03:23:15 PM 
Started by Opcom - Last post by PA0NVD
Patric said that he uses a PI network to match the tube to 200 Ohms instead of 50 Ohms, so there is a resonance circuit, there is a "flywheeleffect". NO difference, just an other output impedance. And yes, when you want to match a high impedance line like a 450 Ohm ladderline, it is better to feed the tuner with 200 Ohms instead of 50 Ohms. Less impedance transformation will give you more bandwidth and less losses.
If you are worried about saturation of core material, you always can use a coax made balun 1:1 without ferrite

 on: October 12, 2018, 03:02:31 PM 
Started by WA2ONK - Last post by WA2ONK
KWM-2A with PM2 power supply. Working, full power out. Has xtals for WWV and two WARC bands. Has an issue that it puts out full power in the Tune position. Cooling fans have been added. $650 picked up.  Chuck....wa2onk

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