MER Level not holding

[g1tzc]

Good afternoon all,

The PicoTuner v3 has been working well but now seems to be having an issue with holding the MER. If you select Beacon MER it is sitting around 7.2 and seems constant.

However if you try to receive anything the MER is shifting from anywhere from 7.4 to -6.1. Needless to say it isn't receiving much more than a single frozen fram now and then.

Also, randomly, it has started not being able to reset the USB bus after the Waiting for Tuner to Respond. The system then goes to the Touch Centre of Screen to Return to Receiver.

Currently running version 202504290.

Thanks in advance,

Neil - G1TZC

[g0mjw]

Try another USB lead and tell us what you are trying to receive because if the beacon is working maybe that's the issue, someone sending something different.

[Pa3fbx]

LO freq is also under suspect.
The beacon is almost 2 Mhz wide.. 300 Khz off is not a problem... but on a 333 signal 300 Khz off is to mutch and the receiver might not be able to keep the fix..

So check the LO of your LNA or just try raising or lowering the LO setting in Opentuner..

Benno

[g1tzc]

Sorry for the long delay. Life rather got in the way of the hobby.

@Benno Yes I am trying to receive the beacon. I thought that was a good place to start. Even if the oscillator was out would that give the USB bus error?

@G0MJW. I have tried several USB leads, including getting a very short one from Pi Hut that I find to be a reliable source.

Other things I have tried;

Replacing the Pico.
Reprogramming both of said Picos.
Running on Portsdown and Ryde software.

Also tried open tuner.

Before I do it, are we allowed to add .mp4 files as I could record what is happening in open tuner.

Thanks.

[radiogareth]

You will probably run into the 'file too big' message. Best way is to upload it to youtube, then copy and paste the link you can share.
HTH
Gareth

[g4eml]

Also are you running the Picotuner on external power or USB power? If running on USB power It takes a lot of current and some USB ports can't handle it.

Colin G4EML


.

[g1tzc]

@Garath - I am running it from external. It has been built in to an old satellite receiver box to keep things neat. The 12v supply runs straight from the back of the unit to the power connect or the Pico V3 board.

@ Colin - I will give that a go after the weekend

I have attached some of the open tuner log files, in case they help. As you can see, I have been experimenting with A&B ports as well. The LNB is powered from an external BIAS-T as there is a known issue with the on board one. I don't have a spare 8 pin regulator (?) IC to replace it with at the moment.

Hope some or all of this helps.

Neil - G1TZC

log files.zip

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