Model:         IC-735

 Division:      Amateur

 Note:          This service bulletin is meant for technical per-
                sonnel with experience working on solid state com-
                munications equipment.  Damage caused by im-
                properly installing this modification may cause
                ICOM to charge for subsequent repairs to the
                product.  ICOM does not warrant this modification.


 Bulletin #:    28Oct-010

 Subject:       If the PLL goes out of lock at high temperature

 Procedure

  1.  Replace R163 (3.3K) on the PLL board with a 1.5K resistor.



 Bulletin #:    03088-001

 Date:          January 30, 1988

 Subject:       Removal of CPU clock noise on 29 MHz

 Procedure

  1.  Remove top and bottom covers from the radio.

  2.  Remove the PA section from the radio.

  3.  Remove the connectors from the PL board and remove the board
      from the radio.

  4.  Remove C10 from the PL board and replace it with a 15 pf 50V
      capacitor (ICOM P/N 918-01517).

  5.  Remove C11 from the PL board and replace it with a 12 pf 50V
      capacitor (ICOM P/N 918-01515).

  6.  No adjustment or alignment is required.

  7.  Reassemble the radio.



 Bulletin #:    8688-001

 Date:          March 26, 1988

 Subject:       If there is CPU clock noise on 29 MHz

 Procedure

  1.  Remove the top and bottom cover from the radio.

  2.  Remove the PA section from the radio.

  3.  Remove the connectors from the PL board and remove it from
      the radio.

  4.  Unsolder the cathode end of D4 and bend the anode lead on D4
      so it is sticking straight up from the board.

  5.  Install L97 (ICOM P/N 924-01948) in the hole where the
      cathode of D4 was removed.

  6.  Connect the free end of L97 and the free end of D4 and
      solder.

  7.  Reinstall the boards and covers on the radio.



 Bulletin #:    13100-001

 Date:          May 10, 1989

 Subject:       Elimination of chirp in CW mode when operating a
                wide split

 Information:   This modification was incorporated in all IC-735s
                after S/N 16801

 Procedure

  1.  Remove the top and bottom covers.

  2.  Remove the main board.

  3.  Add a tantalum capacitor 1.5 mf 35V with the positive lead
      to the collector of Q42 and the minus lead to the emitter of
      Q42.  The ICOM part number for the capacitor is 918-05090.

  4.  Add a tantalum capacitor 2.2 mf 16V with the positive lead
      to the base of Q62 and the minus lead to the emitter of Q62.
      The ICOM part number for the capacitor is 918-01674.


      NOTE:     Spurious emission will result if the capacitors
                are installed with incorrect polarity.

  5.  Check the value of R106 on the main board.  It should be
      22k.

  6.  Replace the main board in the radio.

  7.  Remove the PL board from the radio.  Replace the components
      on the following list.

                Original       New            ICOM
      Part      Value          Value          P/N

      C29       .001mf 50V     470pf ceramic  918-01578
      C30       .1mf mylar     .022mf mylar   918-01686
      R105      220K           47K            915-01183

  8.  Reassemble the radio.