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
 backof 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 still "hot" because
 of the memory-backup battery, so be careful not to short any part of the board during the modification.

 (Source: KB2LJJ)

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