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Doom9
9th May 2004, 16:02
As the title says..

Doc SoLo
12th May 2004, 23:24
Yep, me for instance. :) I'm using a Hauppauge WinTV-DVB-c aka Technotrend DVB-c 2.1 for doing my DVB stuff. Is there anything in particular of interest for you?

Ciao,

Doc SoLo

Doom9
13th May 2004, 10:57
Finally :)
I'm interested which software ships with the card, what its capabilities are, what other software you use for your card, and if you'd be willing to write a short guide similar to the already published 3rd party DVB guides (basically how to scan for channels and record a program). If you're using a program that has already been discussed (I know MyTheatre can handle all kinds of cards), then I'd be interested in the differences there might be in between using the program for a DVB-S and a DVB-C card.

SeeMoreDigital
13th May 2004, 11:05
Where abouts in the world are you Doc SoLo?

I was thinking about getting one of these cards mailed over from Germany, where free-to-view digital cable is quite a big market!


Cheers

Doc SoLo
13th May 2004, 16:32
Originally posted by Doom9
[B]Finally :)
I'm interested which software ships with the card,
I'm pretty sure, the software-CD ist the same as the one the Hauppauge DVB-s cards are shipped with. I did not use it extensively, instead I downloaded the most recent Technotrend Driver/Software-Pack which is the same as for s-Cards. The Hauppauge software is just a relabeled version of these. So I guess there are no functional differences to TT-DVB-s-Cards.
what its capabilities are,
The cards layout is a standard TT premium design, only the tuner is different.

One interesting aspect is that on DVB-s Rev 2.x Boards the "J2-Jumper Block" is not present anymore. Therefore everywhere on the web it is recommended to buy a Rev 1.5 or 1.6 Board. On my DVB-c Rev 2.1 this jumper block IS present. This is important for SPDIF and TV-out since you can get a high quality RGB-signal with an adaptor connected to this jumper block. I'm sure a lot of people get fooled this would not be possible with the WinTV-DVB-c.

what other software you use for your card,
I haven't found my preferred software yet.

In ProgDVB the picture quality is not satisfying. With enabled deinterlacing the picture looks aliased and badly scaled. The same occurs in TT's original software. The software-decoding-mode in ProgDVB doesn't show this issue and provides best quality, but i want to use the onboard-MPEG-decoder for obvious reasons. If someone has a solution for this, I'd like to hear it.

In MultiDec there is a mode available called "Hardware Bob" which produces much better quality. But MultiDec crashes quite often and the channel scan doesn't work.
and if you'd be willing to write a short guide similar to the already published 3rd party DVB guides (basically how to scan for channels and record a program).
What do you mean with "3rd party DVB guides"? I'm not up to date on the state of doom9 anymore (last time I was active on this board was in the good old nandub days several years ago :))

Where abouts in the world are you Doc SoLo?
I'm located in Germany and indeed since all major free-tv-channels are available on cable now the cable-market starts growing rapidly here.

Ciao,

Doc SoLo

Doom9
13th May 2004, 18:35
What do you mean with "3rd party DVB guides"? I'm not up to date on the state of doom9 anymore (last time I was active on this board was in the good old nandub days several years ago )Here are two examples.. they are part of the DVB guide I've written:
http://www.doom9.org/DigiTV/mytheatre.htm
http://www.doom9.org/DigiTV/nebula.html

Since I don't have a guide for any TT standard software I'd definitely be interested in that.. and how does ProgDVB work differently for your card? You'll certainly don't have a Diseq setup screen.. so what do you have to configure to get it going?

Doc SoLo
19th May 2004, 09:45
Ok, I'll try to come up with some information. I had a look at your mytheatre guide and tried to get MT working with my card. No matter what I did I could not get it to scan for channels. There is an entry "DVB-c" on the tab where DVD-s owners select their satellite, but it seems to scan the wrong frequencies. Perhaps the cable-tuner on the TT DVB-c is not supported.

So i have to conclude, that Mytheatre currently doesn't work with TT DVB-c premium.

Ciao,

Doc SoLo

SeeMoreDigital
19th May 2004, 10:04
Originally posted by Doc SoLo
... There is an entry "DVB-c" on the tab where DVD-s owners select their satellite, but it seems to scan the wrong frequencies. Perhaps the cable-tuner on the TT DVB-c is not supported. Now that's interesting. I wonder what would happen if you connected an satellite dish to the end of your cable.... instead of...well... your cable?


Cheers

bb
19th May 2004, 22:36
That would not work, because cable uses different frequencies than satellite. You can't use a DVB-C card with a dish, neither is it possible to use a DVB-S card with cable.

bb

Doom9
19th May 2004, 22:48
@Doc Solo: According to the mytheatre website your card should be supported.. but I'm afraid I can't help you with that.. I don't even use MyTheatre and DVB-C is not possible around here. But they might be able to help with that at the mytheatre support forum.

SeeMoreDigital
28th May 2004, 20:41
This might be interesting...

Somebody called mika, from Finland, posted the following on the JovePlayer forum (http://8dim.com/forum/topic.asp?TOPIC_ID=1433) today: -
DVB-C is working in Finland TTV ( Tampereen Tietoverkko ) cable network. Eg. for TTV, define LOF1 = 3 ( QAM 128 ), add transponder using SymbolRate 6900000, Frequency 426000 and Polarization = Vertical and then scan. You must define LOF1 ( DVB-C use it for QAM selecting ) using value below depending on your network parameters. I think spectral inversion is also used for DVB-C, propably now in "INVERSION_AUTO" mode because it is working.


From DVBCore.h


#define DVB_C_QAM_16 0 // DVB-C: Modulation: 16-QAM
#define DVB_C_QAM_32 1 // DVB-C: Modulation: 32-QAM
#define DVB_C_QAM_64 2 // DVB-C: Modulation: 64-QAM (default)
#define DVB_C_QAM_128 3 // DVB-C: Modulation: 128-QAM
#define DVB_C_QAM_256 4 // DVB-C: Modulation: 256-QAM

#define SPECTRAL_INVERSION_AUTO 2 // automatic detection of spectral inversion
#define SPECTRAL_INVERSION_ON 0 // spectral inversion
#define SPECTRAL_INVERSION_OFF 1 // no spectral inversion

struct TP_INFO
{
DWORD HdrVer; //Structure version. Please check this for sure data is in expected form
WORD wDataValid; //Flag for validating data in wChCount, wChCurrent, all EMMs, all wPMT and all wSID
DWORD dwUserFlags; //User defined flags or variable;
BYTE DiSEqData[32]; //Data for DiSEq
BYTE bDiSEqLen; //Length of DiSEq Data
BYTE bDiSEqToneburst;
DWORD dwSymbRate; //Symbol Rate of Transponder (DVB-S and DVB-C only)
DWORD dwFreq; //Frequency
DWORD dwLNB_Power; //Power for LNB (DVB-S only)
DWORD dwInversion; //Spectral Inversion
DWORD dwLOF; //LOF for DVB-S, QAM for DVB-C
BOOL bF22KHz; //ON/OFF 22KHz (DVB-S only)
DWORD dwViterbi; //Viterbi Rate (DVB-S only)
WORD wChCount; //Quantity of Channels of current transponder
WORD wChCurrent; //Current Channel
CH_INFO Channel[TPI_CH_COUNT]; //Channel Map
CA_INFO EMM; //Array of EMM PIDs
WORD wSatID; //it's a position of Satellite in degrees. i.e.: 0360, 0192, 0050..
//mustbe filled by application before set-up tuner if it supports DiSEqC plugins.
WORD wNetID; //Network ID
WORD wTSID; //Transport Stream ID
} _TP_INFO;[.
Cheers

EDIT: I forgot to point out he was from Finland

Doc SoLo
31st May 2004, 15:38
Erm... I'm not sure what you're trying to say with that post!?

Ciao,

Doc SoLo

SeeMoreDigital
31st May 2004, 16:40
Originally posted by Doc SoLo
Erm... I'm not sure what you're trying to say with that post!?

Ciao,

Doc SoLo Apparently, they are DVB-S settings with an DVB-C card!

Doom9
31st May 2004, 16:52
this is from the mytheatre homepage
DVB-C (Cable):
- Technotrend Premium (SkyStar-1)
- Technotrend Budget PCI
So, your card is supported, but I think the software is by default set to use satellites.. so you need to find out the proper settings for DVB-C cards. Is there nothing on that subject on the Mytheatre support forums regarding this?
http://mytheatre.phpbbhost.info/portal.php
http://forums.dvbnetwork.com/viewforum.php?f=22

I guess a guide is more than needed ;) Too bad I can't investigate this myself.

@edit: here's something I have found that might be useful: http://mytheatre.phpbbhost.info/viewtopic.php?t=468&postdays=0&postorder=asc&highlight=dvbc&&start=15

check the last post.. it tells something about channel scanning for dvb-c

SeeMoreDigital
1st June 2004, 13:27
Can anybody here confirm the input frequency range (in MHz) of these DVB-C cards?

Do they use the same frequencies as DVB-T (40-870MHz)?


Cheers

Doom9
1st June 2004, 15:00
@smd: I meant to add that to the DVB basics.. I don't have the numbers at work but they're somewhere at home.

SeeMoreDigital
1st June 2004, 15:11
Originally posted by Doom9
@smd: I meant to add that to the DVB basics.. I don't have the numbers at work but they're somewhere at home. Thanks Doom9

You know it struck me the other day that as cable TV distribution is via a closed network, there's no technical reason why just about 'any' frequency can't be used - coax cable type permitted!

Worrying isn't it?


Cheers

Doom9
1st June 2004, 15:58
there's no technical reason why just about 'any' frequency can't be used - coax cable type permitted!Well, I think they still have federal regulations on that subject, and I presume that since in the analogue age the frequency ranges were the same, it'll stay like that in the digital age.. bandwidth has not changed (so in regions where you get DVB-T or DVB-C you have less analogue channels via antenna/cable), so frequency most likely won't have either.

SeeMoreDigital
1st June 2004, 17:01
Originally posted by Doom9
Well, I think they still have federal regulations on that subject, and I presume that since in the analogue age the frequency ranges were the same, it'll stay like that in the digital age.. bandwidth has not changed (so in regions where you get DVB-T or DVB-C you have less analogue channels via antenna/cable), so frequency most likely won't have either. I'm not sure whether we have the same kind of restrictions over here in the UK.

Currently NTL, one of our 'analogue' cable providers uses 'active' frequencies of between 72MHz - 576MHz (48MHz - 870MHz being the full range ie: VHF bands 1, 2 and 3 + UHF). They also shove (band 2) FM radio down the pipe.

You may not be aware that UK terrestrial TV only uses UHF frequencies. The VHF frequencies were abandoned when B&W 405 line transmissions were terminated. And as a result, we were unable to buy TV sets with 'wide-band/full-band' tuners (unlike our European cousins).

Anyway... if DVB-C does use the same frequencies as DVB-T, I really can't see why we can't use just one card to do both... there's got to be a solution to this...

DVB-S is a different matter though.


Cheers

Doom9
1st June 2004, 18:11
according to c't DVB-C uses frequency bands 1 - 3 and special channels (not specified), whereas DVB-T can use bands 1 - 5, but mostly bands 4 & 5 are used.

band 2: 48-67 MHz (channels 2- 4) (UHF)
band 3: 175-224 MHz (channels 5 - 12) (UHF)
band 4-5: 471-860 MHz (channels 21 - 69) (VHF)
each channel typically uses 8 MHz and I'm afraid band 1 wasn't listed but I'd expect it to be a low frequency UHF band.

But, as already mentioned in the DVB basics, we have two major imcompatibility reasons: frequency and modulation. DVB-C uses QAM (16 - 256), DVB-T uses COFDM. DVB-C has a much higher net capacity per channel : 38 MBit/s (as DVB-S using a standard transponder), as compared to 14.75 MBit/s. This also reduces the number of TV channels per channel/TS/bouquet.

@Doc SoLo: did my links help?

SeeMoreDigital
1st June 2004, 18:46
Actually your bandings are not quite correct: -

Band 1: 48-67 MHz (VHF Channels 2 - 4)
Band 2: 88-108 MHz (VHF FM Radio)
Band 3: 175-224 MHz (VHF channels 5 - 12)
Band 4-5: 471-860 MHz (UHF channels 21 - 69)

There are slight frequency differences per 'colour system' and even per country. And as you already mentioned the channel numbers will differ due to the overall channel bandwidth allocations.

For instance, China (System D) can go up to as high as 230MHz (C13)and South Africa (System I) can go as high as 253.43MHz (13) for band 3. Even System M can go as high as 885.25MHz (A83). I guess this is why most wideband tuners (certainly the Philips ones) scan from 45 - 890MHz.


Cheers

ronnylov
2nd June 2004, 16:33
I'm using the Technotrend DVB-C 2.1 premium card I have with a CI-interface and viaccess hardware cam and it works on comhem cable network here in Sweden. The software I use mostly is DVBControl and it works pretty good mostly. It does also work with ProgDVB and DVBXtreme but not as stable as dvbcontrol. With ProgDVB I use version 4.07 in hardware mode.

I had to modify the cable.ini file to correctly scan the channels in DVBXtreme. The scanning in DVBControl did not work for me so I did a scan with multidec and then imported the channel list into dvbcontrol. I think I had to do some manual editing of the channel list too.

The bundled Technotrend software worked without problems to scan the channels but it lacks teletext subtitle recording which is a feature I need to get subtitles on some channels. With DVBControl I can record to pva format together with a subtitle file in srt format.

The biggest problem I had where when the cable company swithed coding system. They switched to conax cards but with tunneled viaccess communication and the viaccess cam did not like the new card at all. But reading different forums I found that I had to upgrade my Viaccess redcam to version 4.84 and that could only be done with a satellite receiver tuned to a special satellite channel so I had to send my CAM to someone that did it for me and then at last everything worked again.

SeeMoreDigital
2nd June 2004, 17:34
Hi ronnylov.

Your DVB-C setup sounds kinda cool.

You're the first DVB-C user I know of to detail that your system includes a CAM reader, CAM, and smart-card. Nice of you to confirm that DVB-C is not just for 'free-to-view' services.

You've given me hope that it might be possible, at some time in the future, to obtain official CAM's etc for our NagraVision encrypted DVB-C systems, over here in the UK.

Do you have any frequencies you can list?

Also, do you have DVB-T in Sweden too?


Cheers

Doc SoLo
2nd June 2004, 17:53
Originally posted by Doom9
@Doc SoLo: did my links help?
Not exactly your links, but some other ones I found while searching again. I knew the needed settings pretty well since I'm using my card without any problems with some other apps. MyTheatre works now also but this scan dialog is realy crude. I just didn't get the idea that you can change QAM-Settings via the LNB-box. So these are working settings for me together with some channels and their frequencies:

http://www.pcp-forever.de/~sl/MT-Cable.png

Ciao,

Doc SoLo

Doom9
2nd June 2004, 18:34
@doc solo: so now that this hurdle has been taken, would you still consider writing a few words on the differences on mytheatre when it comes to dvb-c, as well as other software you might be using.

@ronnylov: how would you feel about writing guides on the software you're using for your dvb-c card?

ronnylov
3rd June 2004, 08:54
doom 9: Maybe I can contribute to a guide but I don't have very much time to do it because since I got my first daughter seven moths ago the time does not seem to be enough to keep up with my hobbies. I'll see what I can do, I won't promise anything.

SeeMoreDigital:
I'm at work right now (seems to have more time for the forums at work, hope my boss does not catch me) but I'll check out my frequencies at home. Yes, we have DVB-T here in Sweden too, but you can't receive it with a DVB-C receiver and I have no DVB-T receiver yet. In Sweden there are 7 or 8 free-to-air channels on dvb-t and some additional encrypted channels. I've heard that some DVB-T PC-card user's has got problems now with the encrypted channels because senda/boxer has also changed encryption system but to viaccess 2 and some people may have got problem with their CAM solutions.

We also have Swedish satellite channels sent by Viasat and Canal Digital. Viasat is also changing their encryption system to NDS I think, and it will not work with DVB-S and CAM because it only works in approved receiver boxes and there are no Conditional Access Modules available to buy for their system. But Canal Digital is using Conax and it works with DVB-S cards with conax CAM right now.

I'm searching for a house to buy and probably without cable-tv so I'm not sure if I'm going to switch to DVB-T or DVB-S when I move. Maybe I get both, dvb-t for the free channels and canal digital via dvb-s for pay-tv.

Edit: I have replied in the other thread regarding the frequencies on comhem: http://forum.doom9.org/showthread.php?s=&postid=505548#post505548

Doc SoLo
8th June 2004, 21:36
Originally posted by Doom9
@doc solo: so now that this hurdle has been taken, would you still consider writing a few words on the differences on mytheatre when it comes to dvb-c, as well as other software you might be using.

@ronnylov: how would you feel about writing guides on the software you're using for your dvb-c card?
Sorry, i don't have time for that at the moment. But the differences are really minimal, basically you just have to set whats on my screenshot and youre done.

Ciao,

Doc SoLo

Ishan
20th June 2004, 16:47
Hello people,
I'm using a TT premium (maybe a 2.1 but i'm not sure), here in france we can't get any official CAM for cable so i'm using a "softcam" :rolleyes: (yeaaa i know, that's bad).

I'm using ProgDVB 4.15.1 mainly for recording because it's very stable and it handle teletext subtitles recording as SRT files.

If I just want to watch TV I use the kickass MyTheater in software mode (higer quality than the hardware decoder on monitor)

We also got one HDTV channel here (Euro1080) so i use RitzDVB which is able to handle HDTV through skystar1 card in software mode, by disabling the onboard decoder. (something MyTheater can't do even if it's compatible with HDTV channel)

i had to customize cable.ini for progdvb and also literaly build frequency list for some of the softwares (like mytheater) and symbolerate aren't standard here (6110 and 6875 instead of 6900 for most of the countries).

If you don't know frequency list for ur provider, just scan every 500khz on all the band. it did the trick for me (i've had to build somthing like 10 ini files with 960 frequency for each symbole rate. was a pain but it was worth it)