The long, noisy squelch-tail of the Icom IC-28 (A or H model) 2-meter
transceiver can be shortened by replacing C110 (4.7 uf) with a smaller
value (0.1 to 0.47 uf). (I can't remember the source of this
information.)
I put a 0.33 uf in my IC-28H; it's a very worthwhile modification.
The capacitor is on the bottom board (the one with the lithium
battery), just southeast of IC4 as you face the front of the upside-
down radio. The only difficult part is finding the right p-c pads to
desolder on the back of the board.
To remove the board: Remove bottom plate, unplug speaker. Unplug
coaxial antenna connector (gray wire). Other connectors may remain in
place. Remove 5 mounting screws, one in each corner and one near
center. Tilt the board out of the radio. The button in the upper
left corner is CPU reset; you may have to reprogram the memories if it
is pressed. Remember that, although the radio is off, parts of the
circuit are live so be sure not to short any part of the board during the
modification.
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