Drivers for RT Systems Radio Programming Cables
Installation on the Mac
Allowing the process to complete in Security and Privacy
This process is necessary only for
MacOS prior to Catalina 10.15.5.
Do not complete this process if you are running 10.15.5 or higher.
A driver conflict will arise.

See it done in this video or read about it in the text that follows: Installation on the Mac

All USB devices require drivers to identify the device to the machine and make it work with the operating system. The drivers for the RT Systems cables are distributed with the installation package for the programmer. Double click on the drivers package to begin that installation.

Drivers for RT Systems or Yaesu (SCU-19 or SCU-20 cables) can be downloaded DRIVER DOWNLOAD HERE

Note: Sometimes you don't know the process has failed other than "nothing" happens. That is a failure. If you don't see the Driver Installation window open, the process has been blocked. We can help. Feel free to contact RT Systems at 404-806-9561 (Monday - Friday 10-6 Eastern Time) for assistance.

Step 1: Double click on the drivers package RT Systems Installation Package

Step 2: Driver installation will begin.

Click Continue.
FTM-400 Menu

Step 3: Enter the User Name and Password of the computer.

Click Install Software.
FTM-400 Backup

Step 4: System Extension Blocked message appears.

The message will clearly specify RT Systems Inc. (if installing the RT Systems Drivers) or Prolific Technology Inc (if installing Yaesu Drivers).

Click Open Security Preferences on that screen.
Open Security Preferences

Step 5: In Security & Privacy: Click Allow button at bottom of screen.

The message on this screen will specify "RT Systems Inc" if you are intalling the RT Systems drivers or "Prolific Technologies, Inc" if you are installing the Yaesu drivers.

Driver installation will be completed successfully once permission is granted.
Security & Privacy

Step 6: At the end of installation, you are prompted to move the installer to the trash.

RT Systems recommends you click Keep on this page. Then if for some reason you need to install the programmer or the drivers again, you have the files right there on your hard drive (although you can download them again in the future).
FTM-400 Write OK

Step 7: Close the installation screen and with the cable connected reboot your computer.