G90 sometimes doesn't release PTT

Hi!

As i wrote also in the Facebook group, I have an issue with G90 Xiegu. On a Microsoft Surface 3, the PTT will not released after a CQ call. The tests in the config dialog are working. The Surface has an Atom CPU with 1,6 GHz.

Trying the same on a Fujitso Ultrabook i7 with 2,6 GHz, everything is working like a charm.

I tried different CAT cables with no success. All other digimodes (includes VARA-HF with Winlink) are working.

So, I started to analyze the UART protocol on the CAT line. And I found differences between the Fujitsu and the Surface. I'm confused, because I use the same hardware.

PTT on - Fujitsu:

PTT on Surface:

PTT off Fujitsu:

PTT off Surface:

During the CQ calls, the commands are the same.

Maybe this is the reason for my problems?

Thank you!

73 de Thomas, OE3TBR

EDIT: Could it be, that's the rig type? I guess I had on the Fujitsu the G90 and on the Surface the IC-7200 ... I'm freakn' out ... :-)

16 comments

Comments (16)

OE3TBR

Nov 03, 2022

Best Answer

Hello all!

I fixed the issue. It was a twice-controlled PTT. Here's the story:

I owned a xggcomms.com Digimode-3 TNC. During a sleepless night, I remembered something about a PTT-circuit inside this TNC. Investigating on xggcomms.com website, I found out, that I'm right. This means, I controlled the PTT of my G90 twice, once per CAT and once per TNC.

But I read also on the website: "For use with the X5105 and G90 transceivers the PTT needs to be actuated via the CAT commands. For this, you will need a separate USB CAT interface." - but NOT ON MY G90. I made following tests:

plug out the CAT cable -> the PTT is still working :-)
plug in the CAT cable and mute the audio L-channel of my PC (the L-channel controls the PTT-circuit inside the TNC) -> PTT is also working as expected.

For my case, I want to control the PTT using CAT, so I keep the audio L-channel muted. VarAC is working like a charm - thank you Irad!!!!

Here are some links:

To the TNC: http://xggcomms.com/Xiegu--Wouxon-Shop(2066631).html

To the info regarding the audio channels: http://xggcomms.com/userimages/USB-Digimode-3.pdf

Don't ask me, why the wrong settings were working at one PC and not on the other one ...

Anyway, I'm happy with this solution. Maybe the info helps some other OM's to figure out this kind of strange issues :-)

73 de Thomas, OE3TBR