copied from the Internet:
Newsgroups: rec.radio.amateur.misc
Subject: TM-741 Mod
Summary: All-Band mod for new Kenwood Tri-Bander

Hot off the presses...

To enable FM transmit from 136-174, 410-470, do the following:

1. Remove the front panel.
2. Don't cut the green wire.  If it is cut, splice it back.
3. Disconnect front panel unit cable.
4. Remove two screws in front panel back and remove rear cover.
5. Locate row of resistors next to Lithium Battery.
6. Remove R54 and R55 - clearly marked, the two nearest the battery.
7. Reassemble.  No MPU reset necessary.

Note: Removing only R54 AND CUTTING THE GREEN WIRE enables MARS/CAP only. 
 Removing both AND KEEPING THE GREEN WIRE IN PLACE enables all.

 Fred Lloyd  AA7BQ                        Fred.Lloyd@West.sun.com 
ONE SIDE NOTE, NO RESET IS NEEDED AS MENTIONED ABOVE, BUT IT DOES WIPE OUT THE
VALUES STORED IN THE VFO MEMORIES (AT LEAST ON THE RADIO'S MOD'ED AROUND HERE).

AS LONG AS WE'RE TALKING MODS...

FOR EXTENDED RECEIVE ONLY OTHER THAN THE 144 & 440 (WHICH ARE ALREADY EXTENDED)
YOU ONLY CUT THE GREEN WIRE. THIS GIVES YOU 10 METER COVERAGE FROM 18-54 MHZ,
6 METER COVERAGE FROM 40-90 MHZ, 220 COVERAGE FROM 215-260 MHZ AND 1.2 GHZ
COVERAGE FROM 1100-1400 MHZ.  NOTE THAT THESE ONLY APPLY IF THE SPECIFIC MODULE
IS INSTALLED IN THE RADIO (I.E. 10 METER, 6 METER, 220 OR 1.2 GHZ)...
Tony Bamberger, N6TYG