I found that the interconnecting lead between the boards is too short, but I can fix that later.
Once connected I pressed the microphone PTT and spoke. Not much movement of my external power meter but some.
I tuned around on the FT757, that is still being repaired, and heard myself talking. Using headphones I think the transmitted audio sounds OK.
There was some drift of the VFO when I moved my hand near the tuning capacitor but this should improve when the transceiver is boxed up.
I am putting a socket on the BITX20 to allow me to inject a signal from an external DDS VFO so that, at least at home, I can have a stable signal.
With a full whistle into the microphone I got just over 4 watts output but normal speech hardly made the meter move. I need to look back over the messages on the BITX20 forum to see what others have done for low audio problems.
It is almost time to look at putting my BITX20 into a box and writing up everything I have learnt building it.
Then, once the Aussie dollar improves, I am placing an order for another BITX20 Ver 3 from Sunil and making it work on 80m. This will be the next big project.