Radio Mods Database

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                                               KENWOOD TM-221

The following is a simple modification for the TM-221 rig:

1- Locate the control unit board (X53-3040-XX)
located behind the front panel.

2- Right below the channel select rotary switch and opposite the M.IN
Sw. you will find R24 and R25.(foil side)

3- Remove R25 for 142.00 thru 151.995 Mhz RX TX

4- Move R25 to space for R24 for 138.00 thru 154.000 Mhz TX RX
(Range will vary slightly from set to set)



                    

                                                         KENWOOD TM-211
                                                OUT OF BAND MODIFICATIONS

The following is a simple modification for the TM-221 rig:

1- Locate the control unit board (X53-3040-XX) located behind the
front panel.

2- Right below the channel select rotary switch and opposite the
M.IN Sw. you will find R24 and R25.(foil side)

3- Remove R25 for 142.00 thru 151.995 Mhz RX TX

4- Move R25 to space for R24 for 138.00 thru 154.000 Mhz TX RX
(Range will vary slightly from set to set)

5- Reassemble the radio.

6- Reset the CPU (Press and hold [VFI/M] & [M.IN] and turn power ON.) 


EXTENDED RANGE !!
TO GET YOUR 221A TO RECEIVE FROM 138-174 MHZ YOU
NEED TO REMOVE THE FRONT PANEL AND GAIN ACCESS TO THE CHIP RESISTORS
AND REARRANGE THEN AS FOLLOWS:

R22 R23 R24 R25
X O O X X=CONNECTED O=LEFT OUT

IF YOU ARE RUNNING A VK VERSION REMOVAL OF R24 IS ALL THAT IS NEEDED.
THE TX WILL REMAIN AT 144-148MHZ EVEN AFTER THE MOD.
GEOFF VK3KGH @ VK3RPA

A QUICK AND DIRTY FIX FOR THE KNWD TM231A LOW MIC OUTPUT TILL (IF)
KNWD COMES OUT WITH A FIX IS TO BYPASS R 63 (3.3K).
R 63 AND R64 FORM A VOLTAGE DIVIDER AT THE INPUT TO THE MIC AMP.
R63 IS ON THE BOTTOM OF THE RIG. WITH THE BOTTOM COVER OFF AND THE FRONT
OF THE RIG FACING YOU, LOCATE THE MIC AMP BOARD 3610 WHICH STANDS VERTICALLY
OFF THE MOTHER BOARD. FOLLOW THE 3RD PIN FROM THE LEFT TO R63.
A JUMPER HERE GIVES THE TX AUDIO A NICE BOOST.
BE SURE TO READJUST THE DTMF OUTPUT IN THE MIC (THE ONLY POT IN THE MIC).

                             


All the mods are captured by Packet. 
KB2LJJ    Radio Mods Database 
take now responsibility or liability for any 
damage resulting from this modification.  
                                  
 I have been trying to help our ham radio with the radio modifications and have asked for any type of new radio mods.
 However, I haven't received too many.  If all of you contributed a little more,  I believe I would be able to help 
all the other ham's that are looking for these mods. I know it is possible to get more mods from all the Ham's because of
 the wide range that exist throughout the world.  By doing this we can  flourish and enjoy more of this hobby that 
we've taken part in for so many years. Furthermore, I ask you not to forget to send me any modifications that you might
 have through email.  I would really appreciate it.

      Email                kb2ljj@pacnews.com

 73's
   John Ribeiro
             KB2LJJ