The Wuther

Just by the end of the year 2002 new QRP rig became alive. I called it "The Wuther". The concept of  my smallest rig was taken from experience and some ideas presented in the Web by my distinguished colleagues  - Wayne N6KR, David W0CH, Wayne NB6M and many others. First two Hams mentioned built my enthusiasm to QRP which totally grabbed my all amateur radio interest. Thank you guys and best 72'ss.


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QRPp rig measures 8,2cm x 6,3cm x 1,7cm


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This is my membership card for "tin club"


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Wuther setup ready go...

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Schematic  Ver.1A - Nothing innovative, except parallel capacitor connected to crystals. This  enabled to swing the crystals'frequency into desired segment of  20m band. Fundamental frequency of 14,107 MHz was chosen due to easy purchase of such crystals in Poland. Any questions?? -> mail me


Rig parameters are still under development, but basically :

-     Frequency range: 14,032 MHz - 14,065 MHz  ( good stability)

-    Supply voltage: 9V  6F22 battery

-     Receiver: Direct Conversion with AF filter, suffers little BCI

-     Transmitter:  approx. 150 mW of output power measured on 50 ohm dummy load. Heatsink required

-    Power consumption: RX - about 10mA, TX - approx. 70mA

-    Other:   QSK, TX offset, no room for sidetone circuit :-((

Final comment

I had a great fun building this "rig", but making a contacts isn't easy. I could't work any station I heard since then. This is amazing, that some Hams are having contacts with power of 20mW-30mW, and there is JA5PL who worked WAC with 5mW. Having 150mW I should work someone. My problem   probably lies in the antenna system, which is 3 element beam but coax lenght is 45 meters. Maybe all this little power  soaks on the way to the antenna? Quite different behaviour was on 40 meters when I first tested "Forty-Oner". Using a dipole and driver power of approx.100 mW I could work a lot of  European stations with reasonably good reports. Could anyone explain this?


"The Wuther" Log Book

1 01.01.2003 16:02 SP5COK 559 John in Warszawa - distance about 8km