Channels 6-12 (VHF) with 8 MHz raster width not detected [as102]

cineq

cineq

Vu+ Newbie
Some time ago I posted about a problem (http://www.vuplus-community.net/board/threads/channel-6-12-8-mhz-not-detected.11072/).

angelofsky1980 wrote he'll check driver's sources, but no answer till now. The problem is well described in the mentioned thread, but it seems it has been forgotten.

Can you (angelofsky1980) check if there is any possibility, that the problem can be fixed in the driver or globally? As I wrote in the original thread it doesn't matter if I set manual scan of given channel and 8 MHz raster width. I know some DVB-T set-top-boxes and even TV-sets (my Panasonic Viera) can receive such MUX-es (manual scan must be selected of course). As I wrote my USB dvb-t stick receives these channels under Windows also, so the problem is software only.
 
cineq said:
Some time ago I posted about a problem (http://www.vuplus-community.net/board/threads/channel-6-12-8-mhz-not-detected.11072/).

angelofsky1980 wrote he'll check driver's sources, but no answer till now. The problem is well described in the mentioned thread, but it seems it has been forgotten.

Can you (angelofsky1980) check if there is any possibility, that the problem can be fixed in the driver or globally? As I wrote in the original thread it doesn't matter if I set manual scan of given channel and 8 MHz raster width. I know some DVB-T set-top-boxes and even TV-sets (my Panasonic Viera) can receive such MUX-es (manual scan must be selected of course). As I wrote my USB dvb-t stick receives these channels under Windows also, so the problem is software only.
Click to expand...

I need to know the model of your USB DVB device used.
 
It is being identified as "Aton2 DVB-T USB tuner" under Blackhole software. It has been supported in BH for more than a year I think.

Under Windows we can use PCTV Systems 74e DVB-T Receiver drivers with modified USB ID: Abilis.Device1,USB\VID_0B89&PID_0007

If you need some more information I can get it from my tuner later, just tell (dmesg or some other tool output?).
 
Ok, but I don't think you are able to test DVB-T channels shifted to UHF with 8 MHz raster. Normally 21 and higher channels have got 8 MHz raster width. 6-12 UHF channels have got 7 MHz raster width. This is EU standard. Most older antenna installations in Polish block of flats (40-50 flats for one antenna) were built using low quality cables that cannot transfer higher frequencies. There were only a few analog tv Channels before 90's and these channels were simply transfered to 6-12 channels using simple analog amplifiers. Today in DVB-T era all cables should be replaced with high quality ones, but the cost is the reason 21-60 channels are being moved to 6-12 channels as it was done with analog ones. But the problems is that channel width is 7 MHz for DVB-T 6-12 channels and analog 6-12 channel were 8 MHz width. So now simple shift makes channel 6-12 base frequency different then it is in DVB-T specification.

If I connect private antenna I will receive DVB-T muxes in 21-60 channel range and there is no problem at all. The only problem is many block of flats on Poland use amplifiers that move these 21-60 channels to 6-12 channels but these amplifiers are simple analog devices that cannot reencode DVB-T stream from 8 MHz to 7 MHz. The only reason is cables quality. Anyway as102 USB stick can receive 7 MHz channels in UHF frequencies without any problems under any WIndows application.

I hope you'll fiond the reason ir doesn't work under BH Linux.
 
cineq said:
Ok, but I don't think you are able to test DVB-T channels shifted to UHF with 8 MHz raster. Normally 21 and higher channels have got 8 MHz raster width. 6-12 UHF channels have got 7 MHz raster width. This is EU standard. Most older antenna installations in Polish block of flats (40-50 flats for one antenna) were built using low quality cables that cannot transfer higher frequencies. There were only a few analog tv Channels before 90's and these channels were simply transfered to 6-12 channels using simple analog amplifiers. Today in DVB-T era all cables should be replaced with high quality ones, but the cost is the reason 21-60 channels are being moved to 6-12 channels as it was done with analog ones. But the problems is that channel width is 7 MHz for DVB-T 6-12 channels and analog 6-12 channel were 8 MHz width. So now simple shift makes channel 6-12 base frequency different then it is in DVB-T specification.

If I connect private antenna I will receive DVB-T muxes in 21-60 channel range and there is no problem at all. The only problem is many block of flats on Poland use amplifiers that move these 21-60 channels to 6-12 channels but these amplifiers are simple analog devices that cannot reencode DVB-T stream from 8 MHz to 7 MHz. The only reason is cables quality. Anyway as102 USB stick can receive 7 MHz channels in UHF frequencies without any problems under any WIndows application.

I hope you'll fiond the reason ir doesn't work under BH Linux.
Click to expand...

In my country there is no analog TV and all was upgraded to DVB-T digital standard. In my area there are some DVB services into 7Mhz bw channels.
With some DVB-T sticks I'm capable to tune and view them but I haven't tried with PCTV 74e.
 
There is no more analog tv in Poland too, upgrade process finished a few months ago. I think Europe DVB-T standard is 7 Mhz for channels 6-12 and 8 MHz fo 21 und higher. The same applies in Poland, in fact we have no services broadcasted in 6-12 channel frequencies. Only some older, poor quality multi-socket installations were simply "upgraded" to DVB-T by using amplifiers with analog channel movement. For example: originally received channel 51 is transformed to channel 9. But channel width remains 8 MHz and most TV receivers doesn't support tuning 6-12 in 8 MHz. Under BH I can select channel base frequency and width correctly, but no services are detected after scan. This is the only problem, setting the same channel parameters under Windows with the same stick works ok. There is no problem to tune to "ordinary" 21-60 8 MHz channels using indoor antenna, but the reception is quite poor.

So I think you will be unable to test tuning for 6-12 8 MHz, as I think this was ok for analog tv and now maybe in some other countries. My Panasonic Viera allows to tune such frequencies, but I must select manually channel called "6R" or "9R" which I think is some Russia standard.

Anyway maybe you'll just see something that can be the reason of described problem. If it is possible to set manual DVB-T channel parameters in BH, it should detect services.
 
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