Subject: TM742 freq extension .1

Original from JP1LRT to MODS@WW



Hello!!!! I have recieved message from N8QXP Charles. He asked me mdification


of KENWOOD TM-742. I found it on radio magazine. The modification is very 

simple. But my english is very very poor. I am afraid that you can not make

out. If you have any questions , please ask me again.  N8QXP charles saied


that he do not need graphics. But I need to graphics to explain. HI!



1. Open the lower panel of TM-742.



 ****** There are TWO version. Please check which version your rig is.******



                      FRONT PANEL IS UPER SIDE




      ___                               ___    ___    ___       <<<=== BAND SEL


   ---|-|-------------------------------|-|----|-|----|-|--------

  |                                                              |

  |______________*_______________________________*_______________|

  |     11                    2222                               |

  |    111                   22   22                             |

  |     11                      22                               |

  |11      22                                 |       

  |     11                   22222222                            |

  |                                                              |       

  |                                                              |       

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~





2.   ******  FOR OLD VERSION ******

     SEE THE POINT OF [ 2 ] .If you can find a small board masked with black

     sponge , your TM-742 is OLD VERSION.

3.   On right side small board , there are three lines. Make short circuit

     with midlle line and lower line.





2.   ****** FOR NEW VERSION ******

     SEE THE POINT OF [ 2 ] . If you can not find a small board , your rig is


     NEW VERSION.

3.   SEE THE POINT OF [ 1 ]. There is a chip [ 2R7 ] . And below this chip


     [ 2R7 ] , there are small chip [ 473 ].  



          [ GRAPHIC IS FOR JA VERSION ]

      *-*-*-*-*-*-*-*

              R R R X            R =  chip [ 473 ]

      * * * * * * * *

      * * * * * * * *            Make short circuit two X point.

              X     R            Maybe on your TM-742,there are chip [ 473 ]

      *-*-*-*-*-*-*-*            with different patern. This graphic is for

                                 JA version.  So please try until modification


                                 will succeed.





OPERATION





1. ON 144MHz  PRESS BAND SEL MORE THAN 1SEC .   MODE CHANGE AM <-> FM.

2. ON 430MHz                 DITTO              BAND CHANGE 430 <-> 870

3. ON 1200MHz                DITTO                          1200 <-> 870

4. [F] + BELL  ->  REPEATER DUAL RCV.

5. 118-136MHz  MODE CHANG TO AM AUTOMATICALY.

6. X-BAND REPEATER OPERATION.     SELECT ONE BAND BY [BAND SEL]  SELECT ONOTHER


   BAND BY [CONT SEL].   PRESS [F] KEY MORE THAN 1SEC. PRESS [MUTE] KEY.

   X-BAND OPERATION WILL WORK.

   PRESS [F] THEN [MUTE] KEY -> CANCEL X-BAND REPEATER OPERATION.



73s                DE JP1LRT @ JL1YVX.10.JNET1.JPN.AS

                              YOSHIHARU "KEI" TSUKUURA



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


Newsgroups: rec.radio.amateur.equipment
From: garym@alsys.com (Gary Morris @ignite)
Subject: TM-742A/942A extended transmit mod
Message-ID: <CHsIDA.8E7@alsys.com>
Keywords: mod, 742A, 942A, Kenwood
Organization: Alsys Group, San Diego, CA, USA
Date: Thu, 9 Dec 1993 22:55:53 GMT
Lines: 61

TM-742/942 Extended TX/RX Modification
ASI-0002, Feb. 23, 1993

This is a summary of the modification provided by Kenwood to expand the
transmit/receive ranges for the TM-742/942 tri-band radio.  The sheet is
ASI-0002, subject "TM-742/942 Beyond Mars/CAP Mod.  Guide" and date
"February 23, 1993".  The actual ranges of what the radio will transmit
are wider than what is stated in the table below.

Note: this mod involves desoldering and resoldering a chip resistor, if
you are not an expert in soldering chip components, get an expert to do
this for you.

1. Remove the front panel.
2. Remove the bottom cover from the radio.
3. Looking at the exposed bottom of the radio, orient it so it matches
   the diagram below.
4. Move the rightmost chip resister as shown in the diagram.  The numbers
   "1" thru "8" represent the positions of the 8 chip resistors in the
   original positions from the factory for U.S. radios.  The "x" is an
   empty pair of pads where the number "8" resistor should move to.
5. Reassemble the radio and reset the microprocessor (see manual).
6. Frequency ranges will be:
	28 Mhz band:	RX:  18.0 -  54.0
			TX:  26.0 -  45.0
	50 Mhz band:	RX:  40.0 -  90.0
			TX:  46.0 -  76.0
	144 Mhz band:	TX: 136.0 - 174.0
	220 Mhz band:   RX: 215.0 - 260.0
			TX: 215.0 - 235.0
	440 Mhz band:   TX: 420.0 - 450.0
	1.2 Ghz band:   RX/TX: 1100 - 1400

Notes: not all radios will be able to tune the entire range.

                                                    |
----------------------------------------------------|
              Control Unit X53-346X-XX A/2         ||
                                                   ||
                                                   ||
                                        |          ||
                                        |          ||
                                =-=-=-=-+-=-=-=-=  ||
                                          5 6 7 8  || <-- move "8"...
                                =-=-=-=---=-=-=-=  ||
                                o o o o   o o o o  ||
                                =-=-=-=---=-=-=-=  ||
                                1 2 3 4         x  || <-- to the "x"
                                =-=-=-=-o-=-=-=-=  ||
                                                   ||
                                                   ||
                                            +-+    ||
                                            | |    ||
                                            +-+    ||
                                            2R7    ||
----------------------------------------------------|
----------------------------------------------------|
----------------------------------------------------|
                        Front Panel Area



