CurtPalme.com Home Theater Forum

SisterOfMercy · Posted: Sat Nov 29, 2008 1:26 am Post subject: 1209s quad decoder

Hi all,

Would I be able to run my 1209s without the quad decoder that is currently attached to the RGB input and switching board? I'm not planning on using the video inputs, and I also do not need the sh*tty component transcoder. Do I need to connect J401 on the RGB input board to J402 as mentioned in the service manual, or don't I even have to do that?

And by the way; I've been reading the service manual as bedside material, but what function does the video matrix have? The only thing I can find that uses it is the saturation control. Don't know if that works for RGB, or only for video inputs, I never press those buttons.

**Curt Palme** · Posted: Sat Nov 29, 2008 2:01 am Post subject:

I believe the RGB signals run through the quad decoder, the set won't work without it.

SisterOfMercy · Posted: Sat Nov 29, 2008 2:28 am Post subject:

The RGB signals going to the decoder are present on J401/402. See page 76 of the service manual (page 9 of the quad decoder portion). "Interconnection if decoder omitted", but they don't say anything else.

When looking at the RGB input board schematics the signals are also attached to the output to the RGB driver board. Why the RGB signals would need to go through the quad decoder is beyond me, other than the assumption it has something to do with the saturation controls.

Could I safely try it out by connecting J401 to J402 as stated on that page, or I am I missing something big here?

**Curt Palme** · Posted: Sat Nov 29, 2008 2:36 am Post subject:

You go right ahead.

As I like to say:

'You can...... I wouldn't'.

I'm all for others modifying and playing. If it blows up, let me know, so I don't try it.. Very Happy

Seriously, I don't personally do mods, unless it's beefing up components that are known to fail. I personally won't risk a set failure by pulling out boards that manufacturers designed to be in the set...
Cheers!

Tom.W · Joined: 09 Mar 2006 Posts: 6635

[quote="SisterOfMercy"]Hi all,

Would I be able to run my 1209s without the quad decoder that is currently attached to the RGB input and switching board? I'm not planning on using the video inputs, and I also do not need the sh*tty component transcoder. Do I need to connect J401 on the RGB input board to J402 as mentioned in the service manual, or don't I even have to do that?

And by the way; I've been reading the service manual as bedside material, but what function does the video matrix have? The only thing I can find that uses it is the saturation control. Don't know if that works for RGB, or only for video inputs, I never press those buttons.[/quote

Why do you wish to remove the quad decoder if you may or may not need it ? Wink

r.bauer · Joined: 08 Apr 2006 Posts: 280 Location: The Netherlands

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

YOu don't need the quad card to use the RGBHV inputs. Unless you plan on using Svideo/composite video get rid of it.

Ile · Posted: Sat Nov 29, 2008 5:26 pm Post subject:

SisterOfMercy · Posted: Sat Nov 29, 2008 5:48 pm Post subject:

Don't you need to solder the diode D105 in place when it is missing?

I kind of need the Iris3, the flashy colours are nice Wink

But, I might remove it in the future, never need it anyway.

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

I also removed the iris / the port 3 board and the quad board, this reduces current draw, less heat generated and better air flow with them removed too.

Off hand not sure what diode D105 is, what board is it on?

SisterOfMercy · Posted: Sat Nov 29, 2008 6:34 pm Post subject:

D105 is on the back side of the RGB input board. When the quad decoder board is fitted the signals from J401 and J402 only go through an extra diode on the quad decoder board. In the service manual it says that the D105 (on the input board) is only mounted for the RGB version.
The horizontal and vertical sync signals go through this diode, but after looking at the service manual again I think the H and V sync signals go somewhere else and only need to go through that point when using the quad decoder or the line doubler.

If you guys removed the quad board and it worked, then I'm also set. Going to try it out later.

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

I see which diode you're asking about, you don't need to worry about that(installing) diode.

SisterOfMercy · Posted: Sat Nov 29, 2008 9:18 pm Post subject:

It works, thanks!

For the record; Just remove the quad decoder bord from the RGB input and switch board, and you're done Wink

You really should consider this Curt, as I remember you were looking for a few of those cables. There are four going to every quad decoder board.

Ile · Posted: Sun Nov 30, 2008 7:28 pm Post subject:

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

Oh, forgot about him. I thought we lost him along time ago?

1031 · Joined: 22 Mar 2006 Posts: 657 Location: Finland