Andy,
Skip's recommendations are good to follow.? To restate what he said,?CW is generated when the Nano sets the first LO (CLK#2) to the RF value (either the dial frequency or the Dial frequency +/- the side tone dependent on the software installed) and shorts the first mixer diodes to allow the signal to get through.? If you have a v6, you can set the mode to CW and key the mic to get CW.? If this works, the key/paddle input has a fault somewhere.
If you do not have a v6, verify that there are 5volts when the CW key is up and zero volts when the key is down.? You should be able to measure this at the key.? You can then trace it to the Raduino and then the Nano.
We need to know your version because there are slight differences in the mixer unbalancing.? v4 unbalancing is different from v5, and the key circuits are different from v6.
Assuming a v6 here is the first mixer where the 5volt CW-KEY signal from the Raduino unbalanced (shorts) the diodes in the ring mixer to pass the CLK#2 signal to the LPF that then goes to the transmitter amps.
Checks would be to verify that you do get 5volts on R104 on the CW-KEY side.? Then you can verify with an oscilloscope that you are getting the signal at TP1 on the board.
73
Evan
AC9TU
