connecting dstv to home theatre

[KenMasters]

RGB refers to a system where red green and blue are sent along individual signal lines with a separate h and v sync signal. sometimes the syncs are combined to one line. It is thus typically a 4 or 5 signal system.

With RGsB it's a 3 signal system with the sync info carried along the Green channel. This RGB signal type works over component

Component video uses a differential equation to superimpose one of the colours on top of the other two. the syncs are also carried one one of the colours, this is a 3 signal system. the confusion is that component uses a Red, Green and Blue connector making folks think it is RGB...

Something like that, but just to be a little more correct, it carries the brightness and sync info over one cable and blue and red over the other two. Green is then easily worked out by the TV's colour decoder just by figuring the difference.

[handsome]

ah-ha! so what does the dstv decoder use?

[KenMasters]

ah-ha! so what does the dstv decoder use?

Wait, sorry, just to be clear, I mean RGB can be carried over component, it doesn't mean your TV can accept it though.

[handsome]

my telly accepts the "rgb" signal from the dvd player but not from the dstv decoder......so what gives? different formats?

[KenMasters]

my telly accepts the "rgb" signal from the dvd player but not from the dstv decoder......so what gives? different formats?

I have not idea what flavour RGB scart outputs, it sounds like it could well be RGBHV (Red, Green, Blue, and seperate Horizontal and Verticle syncs, as Hi-Phibian mentioned) which uses 5 cables.

My only experience with RGB over component is with consoles such as the PS2.

[Hi-Phibian]

your dvd player is component, your dstv is RGB H/V.
the two formats are not interchangeable.
Some monitors may allow you to set input parameters to change an input but component to RGB HV as used by dstv requires electronics, not a cable.

Btw, DVD native format in which the picture is stored is Component. RGB on dvd will/should not provide an improvement if all is designed well.
There are boxes from Kramer that take RGB to component and some woulds say that with a component telly this would give best reults but the box costs nearly 2k I think.

[Hi-Phibian]

I meant to say the Kramer box would give best result for DSTV where the native format may be RGB  not DVD..

[handsome]

murky waters indeed. did dstv choose an offbeat output format? there are very few TVs with scart inputs i have seen. do flat screens and avrs accept the different rgb/component formats or is there a standard?

[KenMasters]

Looking it up it seems Scart uses four pins for RGB so that would mean RGBs (Red, Green, Blue plus a composite sync cable) so you would need a four cable connection.

murky waters indeed. did dstv choose an offbeat output format? there are very few TVs with scart inputs i have seen. do flat screens and avrs accept the different rgb/component formats or is there a standard?

You're not really supposed to be using RGB at all. The option is only meant from scart out to scart in. At then end of the day, unless you have a TV with a Scart connection, it'll be a lot easier just going with s-Video (or get an HDMI equipped decoder).

[handsome]

ok................fine.....................i think i will go listen to some records, through valve amplifiers connected to speakers that where made before i was born...sooo much simpler....!

[Hi-Phibian]

It would seem that multichoice has always taken the euro approach, they used to use DIN sockets for M net remember?
ICs are probably available for longer and data sheets easier to comprehend.
Scart is/was big on euro models of TVs but now the Jap way seems dominant, even more so in SA.
What I do not know is what the native format is from dstv, it may be RGB and part of the codec so unlikely to change. conversions incur their own losses so not always a way forward.

[ludo]

......i think i will go listen to some records...

Handsome

To sum up, rant a little, sow a bit more confusion, or maybe clear things up:

RGB has a red blue and green signal line, as a CRT tube has a red green and blue signal requirement. The connectors for the 3 lines have the same colour boots on them, usually BNC. The sync signal, that tells the display to start scanning a new line, start a new frame etc, can be on separate line(s), or added to the green signal line. The sync can be positive, negative...

The more modern way, thank goodness, is YPrPb (on Red/Green/Blue RCAs in consumer gear), where the Y line (green connector) is the luma (black and white) signal and all necessary syncs. Pr is red minus luma, and Pb is blue minus luma. Sometimes we refer to this, wrongly, as YUV, and purists get the heebie jeebies. With some adding and subtracting and gain djustments, the primary RGB signals that CRT monitors used to drive their innards could be recovered from this set of signals. A Kramer box-o-tricks is one way to convert it, but they are sometimes referred to as the bottom feeders of that line of business... (strong purely personal bias warning here.)

If the signals have been digitised, the analog component lines are referred to as YCrCb, to indicate that they have a digital origin. Like analog outputs on the back of a DV recorder. The Cr and Cb colour difference signals are often (always?) awarded less bits in the digitising process to save on data rates. Lossy compression in other words. There are many approaches to this. Apparently the eye is less sensitive to the colour info being chucked away, but quite fussy about brightness information. Marketers prefer the term "Redundant information."

Traditionally, SCART uses RGB, not YPrPb. But a note on the Wikipedia article on SCART says some equipment can have YPrPb there (probably YCrCb nowdays), available from an on-screen menu setup.

As per usual, the manual for the equipment will not state the necessary info, especially not which possibilities have not been implemented by the manufacturer. The buyer may neither be confused, nor informed, you see? It's bad for business, always. Besides, if the buyer can't measure for himself and reverse engineer to figure out what it is that he ended up buying, who does he think he is anyway? Or something like that.

Count yer blessings if there is a picture, and the savages that made the gear didn't put it all in D-Type 15pin VGA-style connectors with pin-outs to their whim, to save a couple of bucks by using a connector that is going obsolete. Or on Hirose HR10A circular jobbies to burn some budget.

Ja. Beat that TV into an amp chassis I'd say.