Ted,
Based on what you have described so far, I believe that you do have a BITX40 with the Raduino board in place of the VFO.? That version does not use the Nano for any of the rig control EXCEPT for the frequency.? What that means to you is if you want to remove the pops, then either the circuit that Paul provided or Allison's circuit on ubitx.net with the 2N7000 inverter in front of it.? This adds another 2n7000 and a 1 meg resistor to the parts list.? You would connect the gate of the inverter MOSFET to the PTT line and the output of the inverter to the diode to the gate of the second MOSFET.? The TX line is connected to the diode with the resistor across it.
Again I must warn that I have not tested this, as I do not have a BITX 40 to experiment with.
Good Luck in protecting your ears!
73
Evan
AC9TU
