Subject: TM-742/(942?) Control Unit X53-346X-XX ***B/2** Mod From: Steve Lampereur Date: Sun, 25 Apr 1999 17:07:36 EDT I have the TM-742 with a Control Unit X53-346X-XX ***B/2** Procedure: 1. Remove the bottom cover of the transceiver by removing the 4 screws on the bottom of the cover and loosening the 4 screws on the side of the unit. 2. Orient the radio so the bottom is up and the front display is near your chest. Near the front display area you will find an metal cover over the a section of the board, remove the two screw that hold it down in front. It will now be necessary to bend the metal cover up to gain access. 3. Locate the grouping of 473 chip resistor pads on the left, above the chip labeled 2R7 This is what the [473] chip resistors grouping look like: ----------+---------- | X X X ----------+---------- o o o o | o o o o ----------+---------- X X X X | X ----------+---------- 1 2 3 4 5 6 7 8 Here is what I have read pertaining to the TM-742 w/ Control Unit X53-346X-XX *A/2* Old version mod, per JP1LRT & N8QXP: Make short circuit with middle line and lower line on all pads New version mod, per JP1LRT & N8QXP: Short the upper part of pad 8, & the lower of pad 5. Universal mod TM-742/942, per VE2PAL: Move the [473] chip resitors on pad 4 up, & chips 7 & 8 down. None of these worked for me with the B/2 contol head. So I figured this out myself. Short the lower part of pad 7. No need to reset the radio, it does that automatically. The automatic repater offset will be disabled. After the mod: 28 Mhz Band: RX: 18.0 thru 54.0 Mhz TX: 26.0 thru 45.0 Mhz 50 Mhz Band: RX: 40.0 thru 90.0 Mhz TX: 46.0 thru 76.0 Mhz 144 Mhz Band: RX/TX: 136.0 thru 174.0 Mhz 220 Mhz Band: RX: 215.0 thru 260.0 Mhz TX: 215.0 thru 235.0 Mhz 440 Mhz Band: TX: 410.0 thru 470.0 Mhz 1.2 Ghz Band RX/TX: 1100.0 thru 1400.0 Mhz Please note that these are theoretical ranges only. Not all radios will be capable of tuning the entire range. For informational purposes only. I am not responsible for damages to your radio. kb9mwr@bigfoot.com -