Problems with PTT via SmartSDR CAT (foot switch)

Hardy · February 2022

Hello!

My setup: Flexradio 6500, SmartSDR 3.2.39, Windows 10 21H2

I connected a foot switch for PTT to a serial port via SmartSDR CAT.

Sometimes the radio doesn't go on the air. There is no transmission power out.

But I can see the audio control and TX flag. See picture below.

If I then release PTT and press again, it usually works but not always.

Pressing MOX with mouse within SmartSDR does alway work.

Any idea?

Hardy · February 2022

Update: This must be a timing bug within SmartSDR CAT.

As soon as I enable "logging" the failure disapears. Disable logging reenables the failure.

Hardy · February 2022

I got the answer from the help desk which solved the issue:

>The CAT COM Port PTT was not originally designed for use with an external footswitch, though many have done this.

>The most common cause of the issue you report is "keybounce" on the footswitch causing inconsistent operation.

I put a 470 nF capacitor between the contact of the foot switch and got success.

KD0RC · February 2022

Good catch! Might be a good idea to submit a help desk ticket with this new info so that Flex can look into it.

Mike-VA3MW · February 2022

Some RS232/USB adapters are flakey. If you search on the Remote part of the community, you will find some discussion regarding it.

BA4KW · February 2022

anti-shake

Mike-VA3MW · February 2022

Welcome!