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

--

Frank      W9MKV
reid@gold.bacs.indiana.edu