Yaesu VX-6R
The VX-6R is an ultra-rugged tri-band (144 MHz / 220 MHz / 430 MHz) hand held FM transceiver that is rated JIS7 submersible (sealed at all openings to permit underwater submersion up to 1 meter [3 feet] for 30 minutes.). It features wide receiver coverage and the Yaesu Emergency Automatic Identification (EAI) system.
The radio can also be purchased or modified to operate “wide-band,” including the Military Auxiliary Radio Service (MARS) and Civil Air Patrol (CAP) frequencies. Note that these frequencies can only be legally used for those authorized with one or the other organization.
While an older class of radio, the ultra-rugged design fills a limited niche.
Wide-band Transmit Modification Instructions
For unmodified radios, here are instructions for enabling wide-band transmission. It involves some basic de-soldering. Following modification, transmission is not literally possible on all frequencies due to mechanical limitations of the radio.
NOTE: All memories WILL BE LOST on completion of this project; backup memories and settings if possible. CHIRP is useful software for radio programming.
1) Remove the battery from the radio.
2) Remove the black cover (you can use and x-acto knife or small flat-blade screwdriver) and the SU-1 (if you have it).
3) There will be two sets of jumpers near the bottom of the window. A set of eight, on the left, with 2 soldered jumpers; A set of five on the right with no soldered jumpers.
4) Looking at the set of eight, count from left-to-right starting with 1. The number 4 & 5 jumpers will be soldered. De-solder the number 4 jumper so it looks like the other non-soldered jumpers.
5) Replace the SU-1 (if you have it), the black cover, then finally the battery.
6) Perform a Microprocessor reset by pressing and holding the [MODE(SP S)SQ TYP], [0(SET)], and [V/M(DW)MT] keys while turning the radio on. The display will say "ALL RESET PUSH F KEY"...so, push the [F/W] key.
7) The radio will now transmit from 137 - 174, 222 - 230, and 420 - 469. It will even transmit on 6 meters (haven't tested the power output on 6m yet).
FINAL NOTE: The radio will also transmit on aircraft, broadcast FM, and other frequencies as well, but be warned this could cause the radio to shut-down and the only way to get it to turn back on is to plug it into the charger. Obviously, I DO NOT RECOMMEND TRYING TO TRANSMIT ON ANYTHING OTHER THAN 6M, 2M, 1¼M, AND 70CM!"