DSD TECH HM-19 Bluetooth 5.0 Module as CAT interface

[DL2RUM]

I discovered another interesting Bluetooth LE module suitable for CAT control for ca. 10,- €. I build a simple CI-V interface for my Icoms. The module requires a 3.5 V - 6.0 V power supply, so I added a 5.0 V voltage regulator board for < 1,- € Both modules pull ca. 7 mA. A 9.0 V battery should be able to power the interface for 50 - 150 hours.
The 3.3 V level fits perfectly to the Icom, for other transceiver brands a level shifter to/from 5.0 V or 12.0 V could be required. There are ready to use boards available.

The interface can be renamed and the baud rate can be changed via AT commands. It is not possible to use this interface for the full TRX control panels, due to the CI-V 19200 baud limitation. I use it mainly for there IC-9700. Pending on my station setup, a USB connection can cause a high noise level on VHF.

On macOS RUMlog version 5.6.6 and on iPad version 5.4.3 or newer is required.

Complete CI-V interface

5.0 V voltage regulator

HM-19 module

Level shifter 3.3 V <> 5.0V

RS-232 level shifter

[ct1drb]

Hello Tom,

as always another very interesting project of you.

It seems a very interesting interface and so my congratulations to you.

I am not sure if I would assemble something like it but it would be very interesting.

Best 73 and have a nice weekend.

CT1DRB
David Quental

[N6KRJ]

Tom,

Can you please provide the schematic?

Thx,

Jim N6KRJ.