Welcome to the Mach-1 Electronics website. 

Our current project is the MultiDigi, A dual radio capable audio and CAT control interface for Amateur Radio.

Updated 4-30-2016 – Evolution continues!

MultiDigi Rev2

MultiDigi REV 2

The Rev 3 Release candidate continues to evolve with feedback from our beta tests and live experimentation on the Frankenstein Rev 2 Test unit. New implementations of EMI/RFI filters has reduced RFI on the incoming data signal lines from 1.5v p-p to roughly 30mv p-p ensuring solid data communications and vastly reducing false data issues.

The Silicon Labs CP2108 UART chip is doing great, and thanks to Silicon Labs PID program, we have our own Product Identifier in the USB chain.

MultiDigi Devices

As you can see, the Silicon Labs UART is customizable and includes the MultiDigi named devices vs the FTDI generic listings in yellow. This was done for the sake of making it easier to locate and assign com ports for software and interconnection with your radio and communications gear.

The back panel connectors have all been changed to RJ-45 modular jacks, While our pin configuration is not a standard, it is easy to replicate and create your own interconnections to your equipment. The Audio connections now incorporate a selectable RTS/DTR pair for PTT keying via the audio patch cable, the data connections are now all capable of serial communications as well as RTS/DTR switching duties.

The RTS/DTR pairs are also now fully isolated via optocouplers and rated to 80v 50ma switching duty.

Also implemented in this revision is a pluggable card method to select TTL or RS-232 voltage levels depending on your needs. This was a requirement based on the fact that not all communications gear is created equally. Icom CI-V interfaces, for example, are 5v TTL logic, while a Kenwood DB-9 serial interface is at +/- 15v RS-232 signal levels. To ensure compatibility with your equipment, and make an easily configurable device, the plug-in card method allows you to set the logic level needed, without hassles of a multitude of jumpers to misconfigure.


Currently at revision 2, it has proven to be a successful design. As of this writing, I have over 1000 contacts logged using a MultiDigi, as with any new designs, there are a few bugs which are being addressed in the upcoming Rev 3 version.  There is also an opportunity for beta testers, if interested please drop me a note at kd6oji@gmail.com.

MultiDigi documentation can be found here: Multdigi Operating Manual


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