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Yaesu Typically Does Not release the extended transmit mod information until a couple of month safter the radio has been out, but I really do need this because of my Navy MARS involvement. After studying the schematic and board for a few hours and looking at other recent Yaesu radio mods, I figured out the mod for the FTM-350r.

Here is the extended transmit mod for the Yaesu FTM-350r:

• Make sure every thingis disconnected from the radio. This includes the power, control head, mic, coax, speakers, and anything else you have connected.

• Open the main radio chassis, removing the fourallen machine screws and lockwashers. The allen wrench is provided in the package. Disconnect the speaker from the mainboard by simply unplugging it.

• With the cover emove d'orient the radio so that the control cable and mic RJ-45 connectors are facing you. Whenyou do this, the main processor will be toward your left.

Locate a series of 3 resistors that are below and to the right of the dimple on the processor. I measure these resistors using my VOM meter and the yappear to be 0 ohm resistors. Thereis an obvious spot were one jumper is blank on the board. I'vecircled the resistors in thispic:

ESPANSIONE DI BANDA YAESU FTM-350_1.png

• Using a very fine solderpen with a very hot tip, carefullyremove the bottom resistor. Thispic shows the finishe dresult with an arrow pointingat the removed resistor:

ESPANSIONE DI BANDA YAESU FTM-350_2.png

• Reassemble the radio and you'regood to go.

Whenyou first power on the radio after performing this mod, you will notice that the radio has reset itself. Ifit Didn't, you probably need to manually reset it.

After modification, the transmit range is as follows:

136-174 Mhz
222-225 Mhz (unchanged)
420-470 Mhz