copied from packet:
Msg# TSF Size #Rd Date Time From MsgID To
38132 BF 4720 0 13-Mar 1600 4X4CV 59967_4X1RU MOD
Subject: KENWWOD MIC MODIFICATION.
The following concerns modificatio of some Kenwood Microphone.
===============================================================
Note:What follows is just suggested, proceed at your own risk.
If you have a Kenwood TM-xxxE (European version) trans', Than your mic,
probably has 1750 Hz baton, Which is useless in some countries (not if
you are a jammer Hi). This baton can Probably be transformed to have
another transceiver function.
I myself, tested the above & succeeded with both:TM-241E & TM-741E (of
which the mic's slightly differ).
-----------------------------------------------------------------------
GENERALLY (at least in the two above) the 1750 Hz baton provides
aprox' 7.5v (when depressed), in order to generate the tone. While the
other 3 control baton on the mic provide lower voltage levels (aprox'
1.5v & 3.5v if i remember correctly). The idea is simply to disconnect
the 7.5v at the baton input & to connect the other voltage level (1.5v
or 3.5, I forgot which).
To do this follow the next modif' stages.
-----------------------------------------------------------------------
MODIFICATION STAGES:
1) Disconnect the 7.5 voltage level by cutting the only jumper on the
print. (to be sure measure 7.5v relative to ground on it, on the 741E
mic it is symbolized by J1)
the TM-741E the TM-241E
ZDDDDDDDDDDDDDDDDDDDDDD? ZDDDDDDDDDDDDDDDDDDDDDD?
3 ZDDDDDD? 3 3 ZDDDDDD? 3
3 3 ptt 3 3 3 3 ptt 3 3
3 3switch3 3 3 3switch3 3
3
3 DD 3 3 DD 3
3 J1 3 3 J3 3
3 3 3 3
3 3 3 3
2) Short the 2 connections on:
the TM-741E the TM-241E
ZDDDDDDDDDDDDDDDDDDDDDD? ZDDDDDDDDDDDDDDDDDDDDDD?
3 ZDDDD? 3 3 ZDD? 3
3 3 3 3 3 3 3 3
3 3 3 3
3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
3 O O O O 3 3 O O O O 3
3 3 3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3 3 3
3 3 3 3
3 1750 VFO MR PF 3 3 1750 VFO MR PF 3
3 3 3 3
3 3 3 3
3Microphone T91-0398-XX3 3Microphone T91-0398-X53
The new function becoms:
^ ^
3 3
3 3
default:call call
programable:PF4 ----
ZDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD?
3 : [[221100 73 DE Ze'ev 4X4CV
=============================================================================
Note:I haven't tried or verified this, proceed at your own risk. WA2ISE
SOURCE: The QRZ Windows Ham Radio CDROM |
