Link to kit manuacturer: http://www.4sqrp.com/n-75.php
"The QRP group just started to ship with the updated daughter board which has better AGC and A.M. detector that mounts on top of the main board.
The 75 meter kit is not a Heathkit with detailed instructions, so an experienced kit builder should be required and patience is needed, but it does work fine.
I am going to try a different microphone adaption (4-pin 3.5 mm plug) and stay tuned for that.
I use a foot switch to turn on 2 different amplifiers (Elecraft KPA-500 & Palstar LA-1K), but any amplifier will work fine. I use to use my Drake L-4B to do the same with these QRP rigs and get about 50 to 100 watts steady output on A.M."