Hi Paul
Congrats on finishing the kit. Yes, the transistor can get a bit hot when tuned for maximum output and it is best to turn the trimmer pot a bit back towards the "cold" end (ground) to lower the output a bit and feel more comfortable.
5.08V p-p into 36 ohms is not 250mW according to my calcs, it's 90mW. I think you have missed a divide-by-2 somewhere.
Another thing to bear in mind is that the output low pass filter is designed for 50 ohm termination, I'm not sure what would change if you use 36 ohms.
72/3 Hans G0UPL
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--- In QRPLabs@..., "PaulG" <pgerhardt@...> wrote:
Got the kit running on the bench still on 12 wpm with 36 ohm dummy load I am getting 5.08V p to p output on the scope. This is somewhere around 250 mw and is set somewhat below max output as max output causes the transistor to run pretty warm. I also found out that you can reverse voltage the PIC enough to cause a 2nd degree burn on the finger and it still seems to be working. I am letting it run overnight or for a few days before I put the antenna on it. Before it started working I had a bad looking sine wave at very low level. Also the final was amplifying this spurious signal. After poking and prodding and reheating some connections it starting running properly.
Pix of it on bench at
