• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Yaesu FTM-350r mod - first on the internet!

Moleculo

Ham Radio Nerd
Apr 14, 2002
9,194
1,674
283
Yaesu typically doesn't release the extended transmit mod information until a couple of months after 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 everything is 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 four allen machine screws and lock washers. The allen wrench is provided in the package. Disconnect the speaker from the main board by simply unplugging it
  • With the cover removed orient the radio so that the control cable and mic RJ-45 connectors are facing you. When you 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 measured these resistors using my VOM meter and they appear to be 0 ohm resistors. There is an obvious spot were one jumper is blank on the board. I've circled the resistors in this pic:
904-1263066572-28ae36f13db802a7cadbc8e4d5034aa9.jpg



  • Using a very fine solder pen with a very hot tip, carefully remove the bottom resistor. This pic shows the finished result with an arrow pointing at the removed resistor:
905-1263066572-dd99a4e0297e4a608b74f99a5c1fe439.jpg



  • Reassemble the radio and you're good to go.
When you first power on the radio after performing this mod, you will notice that the radio has reset itself. If it 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

Enjoy!
 
  • Like
Reactions: 1 person

Converted to PDF file.
 

Attachments

  • YAESU FTM-350R Modification.pdf
    398.1 KB · Views: 1,173
very slick indeed. nice job, moleculo!! we need a review, lol. we have to justify the cost of the radio.


EDIT: saw the review. great stuff. wish i could afford this unit.
 
Last edited:
did any of you notice any reduction in power output after the modifications?


Nope, not at all...although as you approach the edges of the TX range, it's normal to notice some drop in power. This is usually the result of the pass band filters. I don't see any drop in power in the fundamental frequencies.
 
  • Like
Reactions: 1 person
Firmware check.

*** Found 3D with procedure ***


Hi to all !

@Moleculo

Next week should I buy a FTM RTX-350R at a dealer in Hong Kong - 409shop. I have seen with pleasure your video about the operation of radio and defects related to GPS and navigation. How do I know if I buy the radio has already installed the new firmware that fixes the problems?

Your actions are truly beautiful and interesting. Thanks!

Sorry for my bad english.

Very thanks.
 
Last edited:
This is reply of 409shop about FTM-350R firmware upgrade:


"We just ask the Yaesu Company whether the firmware is upgrade or not. And they only reply to us that they do not have announced that FTM-30R have fireware upgrade, it just a gossip"

What about ?

Thanks !
 
:oops: Oh, oh.... well I think I did it right, and indeed the radio is transmitting above 150 Mhz, but do you get a little flashing "UL" that moves between the 2 transceivers and stays flashing on the side that is not currently selected? What might that mean? I can't find it in the little manual.
 

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Tucker442 has left the room.
  • @ BJ radionut:
    LIVE 10:00 AM EST :cool:
  • @ Charles Edwards:
    I'm looking for factory settings 1 through 59 for a AT 5555 n2 or AT500 M2 I only wrote down half the values feel like a idiot I need help will be appreciated