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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.
Содержание IC-7000
Страница 8: ......
Страница 9: ......
Страница 16: ...Label on IC 7000 box 8 Export model Remove the CPU Logic unit Step 1...
Страница 17: ...Unclip the spring clip situated at the back mid right hand side of the radio Step 2...
Страница 19: ...Original 5 5 MHz SMD ceramic filters Step 5 New 6 MHz Ceramic Trap Filters Step 6...
Страница 23: ......
Страница 24: ......
Страница 27: ...Remove the CPU Logic unit Step 1...
Страница 28: ...Unclip the spring clip situated at the back mid right hand side of the radio Step 2...
Страница 29: ...Remove the DDR unit first then the main board Step 3...
Страница 30: ...Very carefully unplug ribbon cables Don t pull on them Step 4 Original 5 5 MHz SMD ceramic filters Step 5...
Страница 31: ...New 6 MHz Ceramic Trap Filters Step 6 Original Diode Positions Step 7...