BATC repeater controller questions

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G4WIM
Posts: 397
Joined: Thu Jan 29, 2015 8:36 pm

BATC repeater controller questions

Post by G4WIM » Sat Sep 27, 2025 11:17 am

Hi guys
I've been working on updating GB3FT which will hopefully be back on air before too long.
As part of this project I've incorporated the BATC controller and been making steady progress.
However I've run into a couple of problems - one I've fixed myself and other is proving troublesome.

First - I found that the DTMF decoder under marginal FM S/N when a tone would drop out then come back caused the decoder to think there were two consecutive inputs of the same type making entering dtmf commands difficult.
To fix this in my shell script every tone has to be different from the previous this means *00# or *11# are not allowed - fairly trivial fixes and much more robust under poor S/N ratios.

Secondly, I'm using a single 4 input Portta switch with input 1 for the BATC controller, 2 for the Ryde, 3 FM rx and 4 for a SRT stream input.
I find that if I have more than one input ie the ryde and streamer and quadmode is enabled it always displays input 1 plus whatever else is active.
I suspect I've got something messed - maybe related to the Portta inputs which are numbers 0 -3 or 1 -4 depending on where you look.

I've studied the code and can't figure it out - I thought some of my MQTT additions in the main.c section may have broken it, but even running the original code seems to show the same problem, leading me to think it's a config problem.
As always, any advice gratefully received.

73 Tim

G8GKQ
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Re: BATC repeater controller questions

Post by G8GKQ » Sat Sep 27, 2025 11:26 am

Hi Tim

Yes, all the controller DTMF testing was done using as fully quietening signal. I'll look at whether adding some sort of "debounce" might make things better.

The design is that if 2 or more inputs are active, the Portta switch should show the quad. In your case, the quad includes the controller. As some HDMI switches cannot only display 2 inputs, I did not add the complexity to switch to anything other than the quad. Given that displaying only 2 inputs means changing their aspect ratio, I don't think that it would gain us much.

Dave, G8GKQ

G4WIM
Posts: 397
Joined: Thu Jan 29, 2015 8:36 pm

Re: BATC repeater controller questions

Post by G4WIM » Sat Sep 27, 2025 11:55 am

Hi Dave
thanks for the quick response.
Re the quad question, perhaps I need to explain the symptons in more detail.

With two active inputs say ryde and FM rx it displays the controller and ryde side by side but no fm - so not quadmode just two screens.
If I add a 3rd streamer input it displays all four.
I was expecting quad mode to look at the active input signal lines and select only those inputs to display based on the fact with two active inputs it display the ryde plus the controller rather than say the streamer.

The Portta switch seems capable of display 1 or 2 or 3 or 4 screens at once depending on mode - hence my expectations.

Maybe I'm misinterpreting how it should work - but having fun and learning stuff as I attempt to sort it out.
Had a visit from Tony G3UIS yesterday and showed him how its working etc.
I've built in a web interface using MQTT to show status and control various aspects of the repeater basically replicating the dtmf functions plus others specific to GB3FT

73 Tim

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