Newsgroups: rec.radio.amateur.misc

From: wa2ise
Subject: mars/cap mod file for the IC2AT

Message-ID: <1992Jan12.201713.26613
Keywords:mod file

Sender: news
Organization: AT&T Bell Laboratories

Date: Sun, 12 Jan 1992 20:17:13 GMT

Lines:49





copied from packet:

 Msg# TSF  Size #Rd  Date  Time From   MsgID        To

10043 BF   2566   1 27-Dec 2052 N2MOD  2631_NY2S    MODS
 Sb:Icom IC-2AT MODs.



                     MODification File For ICOM IC-2AT

                     ---------------------------------

     If you have studied the schematic diagram for this radio,

     you will notice that pins 15 and 16 are not indicated on

     the programmable divider chip IC1 (TC9122).

     By simply connecting pin 15 thru a switch to pin 1, you will

     be able to move the radio up in frequency by 10 MHZ.



     Some of these radios were sold without covering 140-150 MHZ.

     The modification for this extended coverage is described below:

     1) Open up the radio and locate the FLEXIBLE BOARD, this connects

        the thumbwheel switches to the MAIN BOARD.

     2) At the MAIN BOARD end of the FLEXIBLE BOARD, add a jumper at

        location C4.  There should already be a jumper at location C2.

     3) At the thumbwheel switch end of the FLEXIBLE BOARD, remove the

        jumper which connects C3 and COM.

     4) Reassemble the radio.  Coverage is now 140-150 MHZ.(MARS/CAP)



     Now, if you activate the switch described above, the radio will

     now operate in the 150-160 MHZ range, after L3 adjustment,

     described below.



                   OPERATION and L3 ADJUSTMENT:

                   ----------------------------

     1) Activate switch and dial up a known active frequency.

     2) Adjust L3 until PLL locks up and radio begins receiving.

        (you need an active frequency to tell when this happens)

     3) To return to 140-150 MHZ, repeat above steps with switch off.





                     NOTES and DISCLAIMER

                     --------------------

     1) Drill a hole in the case of the radio so that L3 can be

        adjusted from outside of the radio.

     2) The above information is presented for educational

        purposes only, and is not an endorsement of any particular

        practice.

     3) This MOD has been in operation for 6 years with no ill

        effects on the radio

     4) This MOD courtesy N2MOD.

--------------------------------------------------------------------------

Note:I haven't tried or verified this, proceed at your own risk.  And

do not transmit outside of legal bands!  WA2ISE






SOURCE: The QRZ Windows Ham Radio CDROM