April 2021

MAD-Digimode USB interface

The need of an universal PC/radio interface had triggered me to develop this board. Even at the first version I’ve already sold out all the available units so, actually I’m very happy about how it was wellcomed by Ham Radio operators. What differentiate this board from any other commercia board?

  • Fully opto-insulated CI-V / CAT interface for Yaesu and ICOM radios 3kV ESD rated
  • Fully opto-insulated PTT/Key output 3kV ESD rated
  • State-of-the-art Bourns audio coupling transformer with -0.3dB flatness between 200-3000kHz band 3kV ESD rated
  • Fully separate PC/radio masses
  • Universal radio connector on DB9 female socket. Just wire the cable according to your radio pinout!
  • Two separate USB ports one for radio control and PTT/key and one for Audio stream
  • Integrated USB audio codec: it acts as an USB audio card leaving in peace yours computer one!

FTDI is the manufacturer of the USB UART chip that this board uses for the CAT/CI-V and PTT. It’s not a fake chinese copy. You can use MProg 3.5 software from FTDI to modify lines polarities if needed like in case of CI-V reverse polarity signals. You can download MProg >>HERE<<

This first version have no enclosure available, neverthless it works without RFI issues. I’m planning to make a 3D printable model for my second revision.

To full-view the chematic please  “Right click –> open in another window” over the picture.

Here you can download it’s manual as pdf >>HERE<<

It’s drivers for audio and FTDI chip are >>HERE<<

This is the procedure of how to use it on Windows 7 & 10 with Ham Radio Deluxe

From “System device manager” you have to identify the “USB Serial Port” and put it’s identification number “COM22 as example” into HRD startup config dialog. Select also your radio manufacturer, model and baud rate.

Once the HRD to radio connection successed you can configure the “PTT” line as active on “RTS” line asserted. Sometimes thisis not needed because HRD can assert software PTT triggering.

In DM780 open the settings and use PTT by HRD option that you’ve already configured.

The USB audio card is avaiable as audio in/out. Please deactivate mike AGC otherwise your signal will be degraded.