W0CHP.radio

Recently, we made a change to WPSD to help better educate users, and to make WPSD operate better with the various modems out there. However, users have been conditioned by poor documentation to select the incorrect modem type.

If you have been prompted to re-select your modem, or you are trying to find the “STM32-DVM / MMDVM_HS” modem in the Configuration Page, you’ll want to read this document.

What’s Changed

Simple: There is no longer a modem option/selection in the configuration page for “STM32-DVM / MMDVM_HS”.

Why the Change

Because there is and never was such a modem. It was a generic placeholder for some time, but caused more confusion than anything.

How to Select the PROPER Modem in the List

Most hotspots these days use the “MMDVM_HS_Hat” and duplex modems use the “MMDVM_HS_Dual_Hat” GPIO modems (originally designed by our colleagues, DF2ET and DB9MAT).

However, to be certain which modem you have, you can run the following command in SSH to detect your specific modem type:

sudo wpsd-detectmodem

Sample output looks like this:

Detected MMDVM_HS Port: /dev/ttyAMA0 (GPIO) Baud: 115200 Protocol: V1 
	 Modem Data: MMDVM_HS_Dual_Hat-v1.6.1 20231115_WPSD 14.7456MHz dual ADF7021 FW by CA6JAU, G4KLX, W0CHP. GitID #7e16099

Note the text immediately after “Modem Data:”. That is the modem type. So in this case, the correct modem to select is “MMDVM_HS_Dual_Hat GPIO” in the configuration page.

Hint

Ignore the craptacular, poorly translated instructions that accompanied your hotspot/modem that tell you to pick “STM32-DVM / MMDVM_HS”. It won’t work. Follow my instructions above. Eventually the sellers will have no choice but to update their documents.