This information applies to the original FTM-400 radio. Radios purchased after about June 2016 already have the firmware upgrade needed to use an appropriate cable for programming. If you purchased your radio after 2016, you will not need the information of this article. 
 
Programming the Yaesu FTM-400 radio is done with the RT Systems ADMS-M400 Programmer. You can program any FTM-400 radio using a micro SD Card. For radios with firmware version 2.0 or higher, you can use an appropriate programming cable (from Yaesu or from RT Systems).  One even came with the radio when it was new.  The RT Systems software will work with the Yaesu SCU-20 cable.  NOTE;  The Yaesu SCU-20 cable does NOT work on Windows 11.  There is a replacement cable from Yaesu or get the USB-77 from RT Systems for use on Windows 11. 

Only your radio can tell you what firmware version it is. To check:
Step 1: Press and hold for 1 second the [DISP/SETUP] key on the face of the radio to access the menu FTM-400 Front

Step 2: From the menu, select RESET/CLONE.

Don't worry, you won't reset your radio.
FTM-400 Menu

You will find the radio version number at the top of the screen that appears. "Main: 2.0" is what you are looking for. FTM-400 Backup

Click "Back" twice to exit.

If your radio is less than version 2.0, Yaesu has released a firmware upgrade to address the earlier radios.

This is Yaesu's upgrade. They are available at 714-827-7600 for questions. Check at Yaesu's web site for the latest firmware upgrade for that radio (There was another in 2017.  If you are dealing with an original radio, you might want to check with Yaesu about application of any upgrades you find on their site being compatible with that radio.)

If you were using the RT Systems ADMS-M400 programmer prior to doing the firmware upgrade on the radio, be sure to complete Communications| Get data from radio into a New file (File | New) once the upgrade is completed to tell the programmer that the radio has been upgraded. Once this process finishes, you can send your original file to the radio (Communications | Send data to radio) without having to re-enter a single detail.

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