Satellite signal strength 61% but getting audio glitching!

[smilingcrow]

I’m recording JazzFM radio broadcasts from Freesat (Sky) and noticed that quite a few have glitches which occur every 2 or 3 seconds which really spoils them.

I’m only using the Hauppauge USB Satellite receiver to record JazzFM as everything else is happily being recorded via Freeserve.

Is 61% signal strength an issue? This is as reported by DVBViewer. I’m not listing PC specs etc until I’ve determined whether it is a Satellite issue.

[QBox User]

Signal strength may not be a useful indicator for satellite - on all the receivers I have used, it's pretty constant for all signals (or none!) Better to compare signal quality, which is shown in TransEdit Analyzer, or DVBViewer GE. Alternatively, you can View the Filter DVB Source to look for discontinuities.

 

Jazz FM is on Eutelsat 28A, which is a little further East than the Astra satellites that carry most Sky and Freesat services. You dish may be slightly out of alignment.

[smilingcrow]

Signal strength may not be a useful indicator for satellite - on all the receivers I have used, it's pretty constant for all signals (or none!) Better to compare signal quality, which is shown in TransEdit Analyzer, or DVBViewer GE. Alternatively, you can View the Filter DVB Source to look for discontinuities.

 

Jazz FM is on Eutelsat 28A, which is a little further East than the Astra satellites that carry most Sky and Freesat services. You dish may be slightly out of alignment.

Thanks for the info, I did some research yesterday and came to a similar conclusion. I was wondering all along if it was an alignment issue so your input has been most helpful.

 

I’ve run Transedit this morning but it’s the first time I’ve used it so am getting to grips with it.

For JazzFM it gives this info:

 

Packets 760,600

Missing 877

Percent 0.40

 

In the bottom corner it says Quality = 100%

 

I will look at it more over the weekend but any feedback on the above data would be appreciated.

[Griga]

For JazzFM it gives this info:

 

Packets 760,600

Missing 877

The missing packtes are causing the glitches. Are other streams on 11223 V affected? Or is Jazz FM the only one?

 

Here no missing packets with a Hauppauge Nova S2 HD and a small dish (45 cm) in western Germany.

[smilingcrow]

Thanks Griga. I’ve just checked and all the radio channels have a similar missing packet rate roughly proportional to their bit rate. i.e. the 192kb streams have more missing than the 128kb streams.

 

I’ve noticed a discrepancy in that DVBViewer shows JazzFM with a frequency of 11,224MHz whereas there was no entry for that frequency in the list in TranEdit so I selected the nearest which 11,223MHz. It’s a small difference but is that relevant?

[Griga]

It’s a small difference but is that relevant?

Usually it is covered by the catch range of your tuner (+/- some MHz - you can try with TransEdit by shifting the frequency up/down. Click Apply on the right side after each change). However, it may be relevant if your LNB is damaged or quite old and its local oscillator frequency (Lowband LOF = 9750 MHz) is off the mark.

 

If all other frequencies are ok, I'd suspect that the intermediate frequency created by the LNB resp. received by the tuner (11223 - 9750 = 1473 MHz) is disturbed by something. It may even be a source in your PC. Unfortunately there are a lot of possible reasons, including bad cable/connector quality.

 

P.S. If the intermediate frequency gets disturbed, it probably will also affect the highband transponder 12070 H (yielding a nearby intermediate frequency of 2070 - 10600 = 1470 MHz). Check it.

Edited August 18, 2012 by Griga

[smilingcrow]

Thanks. I’m not clear where to look for the possible anomaly at 1,470MHz. I looked at the Transponder list for Eurobird and the range is 10,714 to 12,643 so that doesn’t appear to be the right place to look.

 

I appear to get just drop outs with live listening and not glitching which is a lot worse. But I don’t listen to enough live radio to know if this is consistently the case. I’ve also noticed that it seems to get worse the further into a recording I go. The first x minutes are often fine and then the regular glitching starts. I need to investigate further but I’m tempted to just buy a DAB USB stick as I’m only using the satellite for 1 radio channel. But then I lose DVBViewer support.

 

Does anyone here know if the Compro U680F is supported by your DAB application?

I scanned the web and couldn’t determine which chipset it uses. If not is there a recommended USB stick for DAB; I’m in the UK so we don’t do DAB+ I believe.

[Derrick]

..so that doesn’t appear to be the right place to look.

 

@Griga wrote where to look: 12070H is the closest match in the high band. If transedit shows also many missing packets for this transponder, there could be an interfering RF-source from outside, provided the other frequencies don't suffer from missing packets. Please check other transponders as well...

[smilingcrow]

@Griga wrote where to look: 12070H is the closest match in the high band. If transedit shows also many missing packets for this transponder, there could be an interfering RF-source from outside, provided the other frequencies don't suffer from missing packets. Please check other transponders as well.

Thanks I get it now; I didn’t relate 12070 H with 12,070 MHz.

I can’t check the data streams anymore as when I open Transedit and then click on Analyze I only get the Transponder entries on the left but no longer see the data on the right. I’m new to this utility so no idea what I may have done. I initially thought that the right hand pane had been inadvertently hidden so I grabbed the panel divider but that didn’t help.

[QBox User]

That generally means the transponder hasn't been tuned. You have to choose the correct satellite and an active transponder.

[smilingcrow]

That generally means the transponder hasn't been tuned. You have to choose the correct satellite and an active transponder.

Thanks. I did what I had done previously which was to select a Satellite in the Left hand column then a Transponder in the right hand column and click the Analyze button. It still doesn’t give me the data in the right hand column when I do this.

[QBox User]

That happens to me when I repeat a tuning attempt to the same transponder. I thought it was a driver problem but it could be TransEdit. Tuning to a different transponder, then back again, clears this for me.

[smilingcrow]

That happens to me when I repeat a tuning attempt to the same transponder. I thought it was a driver problem but it could be TransEdit. Tuning to a different transponder, then back again, clears this for me.

Thanks. I’d tried that but it didn’t work. I opened another Satellite and analysed a Transponder and when I tried playing with the mouse to grab the border between the two panels I was able to move it and see the right hand panel. Not sure if this issue points to a bug!

 

In the meantime I have been recording BBC radio broadcasts to test them for glitching and have found none yet. Now that I can analyse the BBC transponder most seem to have 0 with some having 1 or 2 missing packets which should be negligible. Seems like the issue is that JazzFM uses a different Satellite.

The Hauppauge USB Receiver is crashing my system so I think it needs to go back.