TV Tuner

Hello everyone, I have a ‘Compro Videomate TV/PVR FM’ TV Tuner card. Link to the product: http://www.comprousa.com/en/product/m300m300f/m300.html. Something strange really happens in it. Some particular channels, (like HBO, or Disney…) show disturbed video, like the whole picture shifts and makes lines or jumps up and down (and things like that). [If you want, then I can post a picture or two.] Now by elimination method:

  1. It cannot be a problem with the TV Tuner as I had another Tuner before this (of Frontech). The same problem occured in it too.
  2. Not of signal, as when I bring my tv to the same position, the signal is absolutely clear.
  3. Not of some unreadable frequency range as the channel are pretty far apart from each other and occurs with some channels only. (Rest all have pretty good quality picture).
    So can anyone suggest anything to be done?

Some things which might help:
I have 2 PCI Slots, 1 PCI-E, and 1 AGP, in this order, PCI-E, PCI1, AGP, PCI2. TV Tuner is at PCI2 and all slots except AGP are filled. The graphics card (8500 GT) blow air directly towards the TV Tuner. Could that cause a problem. However the disturbance always occurs so I guess not.

I would be thankful for any help

This is just a guess, but are they all premium channels that have the problem? Hbo in particular uses copy protection (at least they used to). They send a signal to the cable box that it is copy protected, and the box applies a macro vision type copy protection if I am not mistaken. Does that sound like a possibility?

Hey thanks, you really added a new thinking dimension for me. But some National Channels are also affected. But really, good idea. Wait, I will check with the cable guy and tell you.

In case I forgot to tell, I use normal local cable, no DTH or anything.

[QUOTE=soumya1323;2140989]Hey thanks, you really added a new thinking dimension for me. But some National Channels are also affected. But really, good idea. Wait, I will check with the cable guy and tell you.

In case I forgot to tell, I use normal local cable, no DTH or anything.[/QUOTE]

I do believe ripit hit it on the head here. The pay for premium channels are the ones that you are having trouble with.

I do believe ripit hit it on the head here. The pay for premium channels are the ones that you are having trouble with.

I didn’t get what you said. Do you mean to say the cable man is doing some tampering with the channels or something. I have to pay him extra or something, I really am not getting anything.:confused:

The channels I have most frequently seen the problem with:
HBO, DD Gujrati, Disney, DD Bengali, ESPN, UTVi (I think thats the name) and one or two more such channels.
P.S - DD stands for Doordarshan and is a national govt. channel in India.

Thank You

Are these channels “scrambled” or do they come in clearly on your regular tv (using a cable converter box)?
Your tuner card cannot “unscramble” copy-protected channels like your cable box can, even if you are paying for these channels. (By the way, with multiple basic packages, even some “basic” channels that once were untouched, may now be scrambled.)
If your video card is a capture card (has video & audio inputs), connect those to the corresponding video & audio output jacks on the back of your cable box. Let the cable box process the cable signal. Let your video card just copy it. You’ll have to set the input source on your video card to “line in” or “aux.” so it will find your audio & video signals, instead of trying to tune in a channel on its own.

hello, the channels come extremely clear in a regular tv, no scrambling there. However I do not have a Cable Converter Box. Simply plug the cable into the back of the tv. do the same with the tv tuner.

Just visited one or two websites about cable converter box, and channel descramblers. Seeing some sample screenshots I think might be that is the problem. Thanks really. Will do some searching around and report back.

Ok, so now I read up quite a good number of articles on video descrambling.
First of all before you say it is illegal and I am doing something wrong, please do some searching. Descramblers are legal, though it “may” be used for illegal purposes (something like the torrent network). My regular Television when connected on the same line shows absolutely clear picture and I pay for these channels twice over, (for two connections: 1 for regular tv and 1 for the tv tuner), and so it is a little unfair that I get bad picture.

I also read that Software descramblers exists, though for PAL only, not NTSC (read up don’t know truth), so I live in India (PAL country), can anyone give some more info.

As for cable converter box, I don’t (actually no-one in this whole city probably) use one. The cable guy just connect the wire at the back of the TV.

Please, Please help

No one said anything about illegal, just trying to get more info to help.
I have not been able to get much feedback on your brand of capture card. Most capture cards will not descramble premium channels and some won’t do half what they say they will.

The channels that you are having trouble with are considered premium cahnnels in most places.
The tuner inside the capture card will not be able to descramble those channels.The cable providers do not want people to record those channels and that’s why they are scrambled in the first place.

A higher end card like the Hauppauge brand may or may not be able to.They are good at taking care of macrovision but I am not sure what India does or uses to scramble channels.

Hopefully someone will come along that is more familar with India cable.

Don’t give up yet, there usually is an answer somewhere.

I’m guessing that if you don’t have a cable box, then you probably have analog cable. There are all kinds of things that they can do to scramble and or cause copy protection with analog.
Be aware of the difference. Scrambling is designed to completely mess up the signal to where it won’t show on anything. The descrambling hardware used would often be on the pole outside, typically in the form of a simple filter. There were several kinds of these filters. Different channels would use different methods of scrambling. It was the channel that mandated what kind of scrambling was used, not the cable company, so whatever method the channel (like hbo or cinamax) wanted is what was used. In fact, people learned how to make and or what to buy to use as filters to unscramble many of these channels. I remember years back, it was as simple as winding copper wire around a tube (it had to be certain dimensions constructed in a certain way), to descramble hbo. You could build a descrambler for a few dollars. I also seem to recall that hbo changed what type of scrambling they had more than any body else. Later on (even while still analog), cable boxes were used and the box descrabled it. there was eventually intelligent descrambling where the cable company could change the descrambling as often as they wanted. They would send a signal to the cable box instructing it on how to descramble the signal each time it was changed. I suppose its feasible that there is a unit like this that is outside on the line somewhere?
Copy protection is different. It is generally intended to allow it to play on a tv, but prevent copying. One of the early ways that macrovision used for vhs tapes was to make one of the video channels weak. It would generally play fine from an original (most of the time and unless the tape was old), but copying would further weaken the signal to the point the video got messed up. I’m not sure how they do/did it with cable (I’m sure that there were several ways used, especially with channels like hbo). I guess that it is feasible that there is a similar weakness in the signal somewhere. It might mess up the picture to the tv, but to such a small extent, that its not very noticeable. When a computer trys to digitize it, it gets confused or has problems with the bad parts, and further messes up the video (preventing you from digitizing it to record it). I do know that some channels would have the cable box apply some sort of analog copy protection. The signal was scrambled, and the scrambling would change so you couldn’t just build/buy a descrambler. The cable box would get updates from the cable company so that it could descramble it, and then it would apply copy protection to the signal before it left the cable box. Fyi, better capture/tuner cards and or ones with stronger tuners tend to do better with copy protection. I’m not familiar with the brand you have as it is not common here though (not sure about the quality). There are video signal enhancers that can take care of some of the copy protections (and I do know for a fact, that at some point in time, they have been effective with copy protection that hbo used).

I think you are just going to have to find out what copy protections are used there. Perhaps you could set your google search filters for local web sites only and try searching for terms like hbo copy protection etc. Do it for the various channels and see what you find. Perhaps someone on this forum from India might see your post if you are lucky too. Here is a hack that worked back in the day (it probably wont help you but it might be interesting to read about using a tin foil slider to tune the descrambler, lol).
http://www.artofhacking.com/tucops/etc/tv/live/aoh_chiccatv.htm
I would imagine, that others there have already dealt with this issue so there has got to be some known ways around it somewhere?
You might also try googling terms like india cable tv hack and look for sites like this.
http://www.hackerscatalog.com/Services/TECH_Notes/eleven.html
and or


In fact that second link might be a good place to ask your question (I don’t know anything about the forum, I just found it googling). Let us know if you find anything.

Thanks for giving the solution, and sorry I was away for so long. Thinking about it, will you just check the images in the attachment and tell whether the disturbance is really because of protection. Please…

ScreenShots.zip (175 KB)

I’m no expert but it looks like it to me.

[QUOTE=ripit;2141895]I’m no expert but it looks like it to me.[/QUOTE]

Same here, not an expert but that is what It looks like.

Thanks for checking them out, now doing search on the forums mentioned, If I come to know of anything new will post it here, and please do so if you all get anything at all.

And by the way bean55 and ripit, thank for giving so much time to my problem :bow:

No problem. Tv tuners in general can be a pain in the but. I have had my share of headaches (mainly because they don’t like less that perfect signals).