Icom IC-7000 Manual page 11

Icom HM-151 modifications (original IC-7000 hand mic)
I have experimented with the original hand microphone that comes with the IC-7000.
One thing I noticed with the HM-151 is that (compared to the HM-103 etc) it has a lot of
bass response, and this also depresses the treble response a bit. Sadly, the IC-7000 do not
have the DSP TX equalizer that I feel should have been implemented. The IC-7000 is an
excellent radio on transmit, but with the HM-151 it's a bit to "bassy" and it sounds to
muffled.
This can be improved by replacing the C30 ceramic capacitors inside the HM-151.
One can use the MIC RECORDING function in the IC-7000 and record exactly the same
phrase before and after the modification to compare and hear the difference.
Remove the rear cover of the HM-151
The schematics below show the HM-151 internal circuit.