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Best way to test power before final

Fokko PH0KKO
 

I have built the Bitx20 for the best part, only the final stage with IRF510 remains. Before I start building the final I would like to check if everything works fine sofar. The reception is great but I am not sure what the peak-peak output voltage on tx should be. I have an oscilloscope and a simple 1 kHz sine wave generator. I intend to feed a signal in (using a 100 nF coupling capacitor) at the mic input of about 20 mV (or more?) but I can adjust that if needed.

What (ball park) output voltage is required and should I terminate it with a 50 ohm resistor when checking on my scope?

kc0wox Leeper
 

Exactly which version of the bitx do you have? bitx version 3 from Sunil? If so, here's a place to start.
http://golddredgervideo.com/kc0wox/bitxver3/bitx20version3.htm
Leonard

kc0wox Leeper
 

I believe I found the answer in my youtube comment. It looks like you are building a bitx20a from scratch. A good place to look to answer your questions is http://golddredgervideo.com/kc0wox/bitxkitsigtrace/txscope.htm  and http://golddredgervideo.com/kc0wox/bitxkitsigtrace/signaltraceindex.htm
Look at The scope probe will be de tuning the basdpass filter while connected to this point. The final tuning of C14 and C18 should be done with the scope connected either at the junction of Q20-R83 or at the dummy load after adjusting the PA bias
The junction of Q20 and R83 going into the pa should have at least 800mv's amplitude.
Leonard