Friday, December 10, 2010

Solidarity -10dB

I've had 21 QSO's with Solidarity thus far. The only DX station worked so far is FG8AR, although W7CNL (Boise, Idaho) is actually located 100km further away. In fact, Jack has reported hearing my signal most everyday of the past week. On one occasion he copied my signal at 569.

On 12/9/10 I connected a step-attenuator in-line with the antenna. On the very same day K8KJ (at 1103km) briefly copied my signal with 10dB of attenuation switched-in (4mW); pretty neat considering the poor band conditions!

Dave, AB9CA, operating near Mobile, Alabama, was kind enough to send me a recording of my signal yesterday. Please click here to listen to my 40mW signal as received at a distance of 1993km. My signal is fairly weak at the beginning but rises considerably by the middle of this recording.

On December 15, I received an email message from DL3PB. Peter noticed that one of my CQ's had been logged by K4TD's automated receiver with a signal-to-noise ratio of 40dB...again, this is with 40mW feeding an end-fed wire over a 1572km path!


The lowest powered station that I have copied so far is K9IS (1258km) using his RockMite at 350mW. Today I worked W4DNE (1379km) while he was running 5w to an attic dipole. That QSO was followed by a contact with N9CX (948km) running 1w from Ohio. Here's a scan of the log as of today. My first contact with Solidarity was with KE4YHY on 11/26/10.

On 12/14/10 I worked W7CNL again. This time Jack was running his Ten-Tec R4020 portable transceiver with an RF output of 4w. He was 569 here on peaks.  


  1. Michael - I'm fascinated with the Solidarity xvcr but am wondering whether it's possible to actually obtain the tubes for this radio? If so, any tips on sources. Thanks! And thanks for sharing your QRPp experiences. This has inspired me to move from kit building to bread-boading or Manhattan style building.


  2. Hi Jim,

    Thank you for your nice comments, OM.

    The ex-Soviet pencil tubes are available on the usual auction sites. A site search for "1J24B" should return a number of hits.

    While I have no experience with them, this supplier appears to have the CK5875 (5875) tube in stock.

    The main reason that I chose the CK5875 is that I had a couple of them in my junk box. Especially as I'm using it triode-connected, there must be a hundred other pencil tube types that would work as well, or better, in this application.

    Good luck and have fun, Jim.

    Mike, AA1TJ