UBITX Ver6 Salvaging the Baofeng microphone for more SSB RF output power!

robert pohorence

UBITX Ver6 Salvaging the  Baofeng microphone  for more  SSB RF output power!

After assembling the latest V6 transceiver, I found the SSB Rf power output was below 1 watt on all bands.

I read many of the Group Posts and decided to make some of my own tests.

I disassembled the mic case, there are just 3 screws.

 The bottom rubber mount will pop off and the PTT switch will also pop out, look carefully at the way they fit as you will have to put them back into place after the modification.

I measured about 4vdc on the Electret mic element.

The mic audio output will work much better with a higher voltage.

I found a schematic in the Group Posts and noticed that the modification of the mic was to Remove the small SURFACE mount parts. My mic PC board had only one surface mount 1.5K resistor. I removed it. (some Posts indicated a 2nd surface mount capacitor soldered across the mic pins, mine did not have that part).

After the modification the mic Red-light will no longer light.

I remeasured the voltage on the mic and it is now about 8vdc , almost double the unmodified mic.

I also read in the Group Posts that it is probably a good idea to open up the small mic hole in the face of the mic, I used a 5/32-inch drill bit and drilled from the front of the mic opening the mic hole.

Using a Peak reading RF wattmeter, the meter now went up to the full CW power output.

I have not made any SSB contacts yet due to super poor propagation, so I don’t know how the audio will sound, but I did check the audio on my ICOM 7300 and it sounded OK.

Rob N8RT

Rob N8RT

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