TV Server: weak DVB-S signals (2 Viewers)

[mm1352000]

Hi chschs

Can you please post your TV Server logs so I can confirm that the patch is actually needed for your card. There is a link in my signature to tell you how to do that if you don't know how.

Thanks

 

[chschs]

AW: Re: TV Server: weak DVB-S signals

I hope that what you want to see is in there.
If not, let me know.

 

[mm1352000]

Hi again chschs

I can't tell from your logs whether my patch is having any effect or not. It appears like your signal is just fine:

dvb:  LockedInOnSignal locked: True, present: True, quality: 98, strength: -3500

The reason why I created this patch is for users who were getting something like...

dvb:  LockedInOnSignal locked: False, present: True, quality: 98, strength: -3500

TV Server usually detects that a tuner can tune to a channel using *only* the "locked" value. If locked is "true" then the tuner can tune, otherwise it can't. In my case, when I tried to watch channels on weak transponders the tuner said it wasn't locked ("locked: False"), however it also said that it had detected the signal ("present: True")...

I did notice other things in your error log which are more likely to have been the problem:

TvLibrary.TvException: Unable to start graph

This patch is not meant to solve that issue. Having said that, if you think the patch helps then you're welcome to keep using it. I should say that it is *very* unlikely that this patch would get added to MediaPortal (at least for version 1.*) because it would require too much user testing (to confirm that *every* tuner still worked)...

 

[chschs]

AW: Re: TV Server: weak DVB-S signals

Thanks for you quick response.
You are right (unfortunately ;-) The problem is back, despite of your patch.

Yes 'unable to start graph' is the symptom.
The 2 DVB-T cards seem to work just fine, but the DVB-S card causes problems now.
I am about to try installing an older driver for the card.

Since a while the system hangs if running a couple of hours.
Then one of the processor kernels is at 100% (P4) I have tried to cancel all the processes - does not change anything.
Shut down the whole computer is the only thing that works.

Was reading a lot of posts regarding: Unable to start graph. I think it is related to the card.
No prob on the DVB-T cards at all - only on the DVB-S.
In that moment the channel scanning does not find anything on DVB-S - therefore no tuning.
But why? Have you got any hint for me?

 

[mm1352000]

Hi again

The only hint I can offer you is to say that the "unable to start graph" message means that the tuner did not do what TV Server asked it to do. It seems to be an indication that there is an internal driver error or other hardware problem. For that reason I think it is definitely a good idea to try older drivers.

Have you always had these problems with the DVB-S tuner?
What version of MediaPortal are you using? (I know that the system listed in your profile says version 1.1.2, but I want to be sure...)

 

[bendtsen]

Hello all,

I am following this thread with interest as I think the exact same problem applies to analog tuners. I guess I am soon the only person in Sweden still using an analog tuner, but there are providers with analog content even though the analog broadcasting network was shut down and replaced with digital equivalent a few years ago in Sweden.

My problem is that sometimes my analog channels work, after rebooting or hibernating they don't work. I can't really see a pattern so I'm guessing the signal might be weak, and MediaPortal runs into trouble. I have the exact symptoms as described in this thread with DVB-S signals, i.e. tuner is found, set to a specific frequency, but it fails to lock onto the channel. I suspect MediaPortal (through the card's driver?) thinks the signal is to weak to attempt to start reading video and audio.

I would be very happy to receive a patch for TV Server and analog tuners. I noticed that the trace output from this patched DLL was printed in the log only for my TechnoTrend DVB-C card which has always worked perfectly with MP. But for the analog card, a line similar to "dvb: LockedInOnSignal locked: False, present: True, quality: 98, strength: -3500" wasn't printed. Maybe its not part of the patch and is in the regular and released MP code but only printed for DVB?

I would be happy to create the patch myself if someone told me in which source file this is implemented.

Thanks and best regards,

Mikael

 

[mm1352000]

Hi bendtsen

Analog tuners are *very* different to DVB tuners. With analog tuners, the driver doesn't actually provide signal strength or quality measurements. It is either (1) no signal, (2) signal present, or (3) can't be determined. Up until now TV Server has been expecting the tuner to return "signal present" if it is locked. A patch has been accepted for 1.2.0b+ that will make TV Server think that the tuner is locked if the tuner doesn't return "no signal". You could try the patch that I linked (it is for TV as well as FM radio), but to be honest I don't really think that is the problem. I think the drivers for your analog tuner don't like hibernate/sleep. I suggest you update to the latest version of the driver and search the internet to see if there are other people that have the same tuner as you and that experience the same problems as you after the computer wakes from sleep.

 

[bendtsen]

OK! Are you saying that if I get the "No signal" message in MP, that actually reflects what the driver reported? What then puzzles me is why this card ALWAYS works in the bundled software despite standby/hibernation. Obviously, some workaround, reset or reinitialization is performed. I will try to find updated drivers, but I doubt Hauppauge provides it as drivers for their analog tuners are likely treated as legacy software.

Maybe I should point out that even cold starts or reboots don't address the problem, hence my theory of a signal that is varying and is sometimes below the threshold.

- Mikael

Hi bendtsen

Analog tuners are *very* different to DVB tuners. With analog tuners, the driver doesn't actually provide signal strength or quality measurements. It is either (1) no signal, (2) signal present, or (3) can't be determined. Up until now TV Server has been expecting the tuner to return "signal present" if it is locked. A patch has been accepted for 1.2.0b+ that will make TV Server think that the tuner is locked if the tuner doesn't return "no signal". You could try the patch that I linked (it is for TV as well as FM radio), but to be honest I don't really think that is the problem. I think the drivers for your analog tuner don't like hibernate/sleep. I suggest you update to the latest version of the driver and search the internet to see if there are other people that have the same tuner as you and that experience the same problems as you after the computer wakes from sleep.

 

[mm1352000]

Hi again

OK! Are you saying that if I get the "No signal" message in MP, that actually reflects what the driver reported?

Well you haven't posted logs so I can't be sure, but usually that is the case. If you posted logs then I could confirm...

What then puzzles me is why this card ALWAYS works in the bundled software despite standby/hibernation. Obviously, some workaround, reset or reinitialization is performed. I will try to find updated drivers, but I doubt Hauppauge provides it as drivers for their analog tuners are likely treated as legacy software.

Maybe I should point out that even cold starts or reboots don't address the problem, hence my theory of a signal that is varying and is sometimes below the threshold.

So signal is *always* okay in the bundled software, but only sometimes okay in MediaPortal (even from cold boot)? What happens if you restart TV Server after resume/hibernate?
Two things to say in response. First, please can you tell me the model number of the tuner. It could be a hybrid tuner that you would need to set up correctly in order for it to work properly. Second, I hope you're aware that a tuner can't be used in multiple applications at the same time.

 

[bendtsen]

Attached are logs from reproducing the problem (extracted with the built-in debug mode of MP 1.1.0)

Restarting TV Server after resume/hibernate doesn't help. Tried 15 cold boots and 15 hibernate/resume.
Model number of the tuner is in the logs, the Hauppauge card. Let me know if that specific card needs specific set up in order for it to work properly with MP. I am aware that a tuner can't be used in multiple applications at the same time. That is not what I am trying to do. IF some other application has locked the tuner, how would I find out? Can use some tool from Sysinternals to find out which process has a device locked?

Best regards

Mikael