Unable to tune channels - Compro DVB-T200 and Hauppauge HVR-1200

[Andy_L]

I've bought two TV cards, if I can get one of them to work with GBPVR I will be very happy
Unfortunately neither seem to be able to properly pick up DVB-T channels during scanning, though the results are slightly different with each card.

With the Hauppauge WinTV HVR-1200 PCIe card, the config app shows strength 0 and quality 0 all the time and finds no channels.

With the Compro Videomate DVB-T200 PCI card, it successfully tunes channels on the first mux (BBC1, BBC2, BBC News and CBBC), but for each successive mux it just finds the same four channels again. Someone else posted about the same problem with this card, it seemed the card was not complying with GBPVR's instruction to switch muxes during the scanning process. The four channels it does find, I can watch OK.

I've attached the config logs from both attempts at tuning. I'm using GBPVR 1.4.7. Hoping someone can shed some light on either of these problems...

[Graham]

Is it a reception thing? My understanding is that computer TV stuff is less sensitive than real TVs. Have you tried each card after removing all splitters and connectors on the ariel cable?

[Andy_L]

Thanks for your reply Graham. The reception quality is a good question. I don't have any other DVB-T receivers to test it with apart from these cards. I can only say with certainty that the aerial is OK with analogue TV from the same transmitter. I have removed a splitter from the downlead, but there is still a connector that I can't really do anything about without running a complete new cable.

I think the fact that I can view some channels on the Compro card does imply I have at least some reception though.

I've tried a couple of other apps now as well. I downloaded "DVB Dream", and it exhibited similar symptoms. No signal at all on the Hauppauge, and it only tuned to channels from one mux on the Compro - but a different mux to the one GBPVR picked up.

I've also tried a command line utility called ScanChannelsBDA. It also found nothing at all with the Hauppauge - I'm beginning to suspect a hardware fault with that card.
With the Compro, it detected a bunch of channels on 4 or 5 different muxes. It reported signal strength 0 on all of them (probably a reporting error?) but signal qualities ranging from 34% to 100%. So the Compro can definitely detect a lot of other channels, if only I could persuade GBPVR to tune them!

[Graham]

I have solved similar problems with a signal booster ... one input and multiple outputs plus a dial to vary the signal gain. Check the gain (in db) before you buy because they are not all equal. B&Q have lots.

Broadcast signal strength is boosted at switchover ... if you can wait that long.

Before I fixed my problems, I got variable results ... some muxes worked and others didn't ... some muxes worked one day and not the next and so on.

It has been my experience that reception for viewing and recording can work even though scanning fails. In the BDA folder in the GBPVR install directory you will find scan cacche files. If you ask nicely and tell us your transmitter, some kind soul will post a scan cache file that should work and allow you to bypass the scanning process.

[Andy_L]

A bit of further info - I downloaded Compro's own TV app (don't know why I didn't think of that before!) and it picks up 60-odd channels, which all work perfectly apart from a few on Crystal Palace multiplex A (broadcast on low power) that are breaking up.
Unfortunately their app is pretty poor so I'm hoping I can find a way to make it work with GBPVR. I tried doing a manual scan and entering a frequency that I knew should have some channels on it (530000kHz = UHF28) but I just got "Unknown 2" appearing hundreds of times in the list of channels found.

[sub]

There have been a few Compro devices in the past that seem to ignore GB-PVR tuning requests for some reason, and this sounds like the case here. Something quirky about the Compro drivers that dont like the way GB-PVR does things.

Its a pity your HVR-1200 doesnt seem to be functioning, because I'm sure that would work with GB-PVR correctly.

[Andy_L]

Hi Sub,

It's not just GB-PVR either because as I mentioned I got similar results with DVB Dream. Though on that I got the channels from the mux on highest UHF channel, because I guess that starts scanning from the top downwards.

I've put in a support request to Compro to see if they can provide any driver reference documentation or similar that might shed some light on why their cards don't behave like everyone else's... I won't hold my breath on it though

I'm wondering if there's any way I can work around it by setting channels up manually. The ScanChannelsBDA app I mentioned gives me information like this:

Code:

Frequency (As Locked) = 482000kHz

Frequency of Parent Transmitter  = 481833kHz

Network/Region Name = London.
Freeview Multiplex  = Mux 2
#Relay transmitter frequencies
#Network_1("London.", 658166, 8, 1)
#Network_1("London.", 746000, 8, 1)
#Network_1("London.", 474000, 8, 1)


Channel Name           LCN   SID    Vid   Aud   PMT
-------------------------------------------------------------------
ITV1                ,    3, 8261,  520,   521,  256    #
ITV1                ,     , 8261,  520,   522,  256    #
ITV2                ,    6, 8325,  530,   531,  258    #
ITV2                ,     , 8325,  530,   532,  258    #
Rabbit              ,  102, 8643,    0,   789,  274    #
Channel 4           ,    4, 8384,  560,   561,  264    #
Channel 4           ,     , 8384,  560,   562,  264    #
Channel 4+1         ,   13, 8452,  580,   581,  268    #
Channel 4+1         ,     , 8452,  580,   582,  268    #
E4                  ,   28, 8448,  570,   571,  267    #
E4                  ,     , 8448,  570,   572,  267    #
More 4              ,   14, 8442,  590,   591,  270    #
More 4              ,     , 8442,  590,   592,  270    #
Heart               ,  216, 8772,    0,   631,  284    #

Is there any way I can convert that into a configuration that GB-PVR can use?

[Andy_L]

I'm wondering if there's any way I can work around it by setting channels up manually.

Just thought I'd post a quick update on this - after a bit of experimentation it seems the answer is yes. I located the channels that GB-PVR found in the file C:\Program Files\Devnz\GBPVR\BDA\scan-2.cache. Using an application called TSReader Lite I've been able to glean all the channel data I needed to add channels manually to that file, and successfully watched them in GBPVR. I'll post some more details later if anyone's interested.

[clayt_d]

Hi,

I've gone through the same thing many times with the compro T300 card.

It is possible to offset the frequency by a couple of KHz in the .ini file to make the compro cards "see" the channel information when autotuning - although it is hit and miss, and not very good for subsequent viewing unless you change the frequencies back to their proper values in the scan.cache before mapping them in GBPVR.

I've posted my scan.cache file for Winter Hill UK which has gone all digital, you should be able to paste in whatever is missing into your own cache file, or search-n-replace the file in it's entirety.

(Red Hot and some other adult channel are missing - I am usually way too drunk to operate anything except a bottle opener by the time it comes on)

I understand that the channels carried are the same throughout the UK, the only differences being regional programming supplied by the BBC, ITV and Channel 4 in wales, as well as some radio stations for Wales, Scotland and Ireland.

The following changes will need to be made to the scan.cache file, which can be gleaned from TSReader:

Example:
T:C62,801834,0,0,8~NID:12330~ONID:9018~TSID:4168~P:4168~V:101~A:102~L:eng~PMT:100~LCN:1~PCR:101~N:>BBC ONE

T:Cxx,xxxxxx - change to your local Mux channel and frequency. Remember to apply the 166KHz offset if needed (shown as Cxx+ or Cxx- on the freeview site).
The example above shows BBC1 on C62- The centre frequency is 802000KHz, in my case a -166KHz offset needs to be applied.

NID:12330 - change to your regional network ID. (London). Example is North West (Granada Region). In the UK the same number is used on all Muxes in a region.

TSID:4168 - will need to be changed per region. Definitely ITV1 and BBC1 Mux (C4 is on the ITV1 Mux), I'm unsure about the other 3.

P:4168 - Program (channel service) ID. BBC1, BBC2, ITV1, ITV2+1 will need altering on a regional basis (and C4 in wales). Some radio stations too. If it is wrong you can still probably receive channels, but the broadcast EPG will be empty (or wrong).

Remember to update your BDA/xxxx.ini file to reflect the new frequencies (because of the freeview retunes). It still won't get your T200 to autotune (and isn't needed if you edit the scan.cache file directly), but if you ever add another card it will tune from that file.

Winter Hill and Crystal Palace broadcast HD ITV1 and BBCHD on a separate Mux. No current DVB-T cards can decode it, but add it to your ini file anyway if you plan on getting a DVB-T2 tuner in the future. GBPVR tries to scan it and moves an if it isn't supported by the card.

[clayt_d]

Updated frequency list for Winter Hill (A) to drop into the BDA\DVB-T folder for autotuning. Covers the Manchester and Liverpool areas.

The HD Mux is correct frequency-wise, but will need correcting on the other parameters (no DVB-T2 card to test).

The UK Freeview retune has shifted many frequencies around all over the country. Winter Hill lost it's analog TV in December 2009, the digital frequencies in the file are now the permanent frequencies for digital TV from this transmitter.

Apologies to sub if this has been posted elsewhere (and for following different naming conventions).