talkback mod on cobra 29 lx

[doc919]

Ok! I have done the mosfet conversion with "peak&tune". Here's the deal! I have also done the talkback mod where you solder the top of the 2 resistors together to make it louder & for some reason I just noticed today that when I am just listening, if I turn the talkback all the way up, it increasesthe volume of the receive. (Not the S units. Has anyone else noticed this? Radion is transmitting & recieves well. Also I did try the homebrew dipole on my semi. & it works very well

 

[CB RADIO FREQ]

Ok, the reason that the recieve comes on with the talkback is because when you short the two negative contacts on the EXT SPKR and PA jacks, it causes the radio to think there is a recieve line attached. This will also happen on the cobra 29, 148, 2000, ect.
The reason the talkback does not turn the recieve on full blast is because there is resistance in the control pot and it isn't fully shorting the two points together. This should be your problem but overall don't worry about it. The radio will still perform the same.