HR2510 Modification for increased MicGain

This mod will increase the AM modulation.

The AM modulation adjustment is VR114, which is marked ‘AMC’ on the main circuit board.

To get more, Q114 is the Mic Attenuator, This limits the audio.

 Q114 is located near the front of the circuit board in the center to the left of IC 104, above C153.

 To modify this, remove Q114 and bend the Emmitter leg up from the circuit board and re install.

Put a 1000 ohm resistor in the vacant hole and solder to the board.

 Solder the other end of the resistor to the Emitter leg of Q114.


 This will allow more modulation with the ‘stock’ mic, and will allow a Power Mic to truly perform! The AMC control will still function so using a modulation meter you will be able to set it to avoid overmodulation.

Another Mod Suggests Clipping D129 to remove the ALC and AM limiting. I have heard from one user that this mod works exceptionally well.. I have not tried this mod, If anyone else has , please let me know the results.