Author Topic: CPC scart cable problem - 1980's CRT  (Read 459 times)

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Offline garycpc1987

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CPC scart cable problem - 1980's CRT
« on: 10:16, 09 April 20 »
Hi,

Firstly, thanks for adding me to the forum.

I've recently bought a pristine 1980's 14" Griffin audio CRT TV from ebay, what really drew me to this was it has that 80's look (obviously) and comes with a scart AV input, which unless I'm mistaken is quite rare on a set dating from this period. The TV automatically switches over to AV and detects whether the input is composite or RGB, I've plugged in a DVD player with RGB over scart and it works perfectly.

The problems comes with the CPC scart cable which I bought from cool novelties, while this works perfectly on my relatively modern 40" Panasonic LCD flat panel when plugged into the 14" CRT the picture rolls around and is completely unusable, see the atttached video (video looks exactly as it does in real life). I assume this is something to do with the TV not liking the sync signal from the CPC but I'm not sure, if someone could maybe throw some light on maybe why this isn't working that'd be great as I'd really like to use the 80's set with CPC if possible as it looks good and suits the set up perfectly.

Thanks in advance.

Gary.

Offline Gryzor

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Re: CPC scart cable problem - 1980's CRT
« Reply #1 on: 12:07, 10 April 20 »
Damn that's a cool TV :) I want one...

Offline garycpc1987

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Re: CPC scart cable problem - 1980's CRT
« Reply #2 on: 18:50, 10 April 20 »
Thanks, I know  :D ..... that’s why I’d love to have it working with my CPC.


Offline tjohnson

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Re: CPC scart cable problem - 1980's CRT
« Reply #3 on: 20:31, 10 April 20 »
could it have something to do with the capacitor that is inevitably inside the scart cable?  Maybe try cutting one leg of the capacitor and seeing is that helps.

Offline garycpc1987

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Re: CPC scart cable problem - 1980's CRT
« Reply #4 on: 18:50, 11 April 20 »
No capacitor fitted I'm afraid.
Thanks though.

Offline tjohnson

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Re: CPC scart cable problem - 1980's CRT
« Reply #5 on: 22:16, 11 April 20 »
This is a passive or active cable?  How long is the cable?

Offline garycpc1987

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Re: CPC scart cable problem - 1980's CRT
« Reply #6 on: 18:47, 12 April 20 »
It's active, it takes the 5v feed from the CPC PSU.
The cable is around 1.5m long.

Thanks.

Offline tjohnson

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Re: CPC scart cable problem - 1980's CRT
« Reply #7 on: 19:10, 12 April 20 »
Have you tried it without the 5v? Although that would probably just make the screen monochrome if the TV doesn't switch to rgb, looks like a sync issue, is there a dial on the TV to adjust the sync hold?
« Last Edit: 19:12, 12 April 20 by tjohnson »

Offline 1024MAK

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Re: CPC scart cable problem - 1980's CRT
« Reply #8 on: 11:59, 13 April 20 »
I agree that it looks like a synchronisation issue, in fact it looks like it’s just the vertical (field) sync. that is the issue.

Before speculating, I’m gonna ask a few basic questions:

The forum shows a Union Jack so I presume you are in the U.K.?
Is the CPC a U.K. model?
Is the TV a U.K. model?

In other words, are both designed for a 625 line / 15625 Hz / 50 Hz system I TV system (PAL-I)?

If the answer is yes, then have you tried any other 8 bit or 16/32 bit home computer on your Griffin TV (via SCART or via any other available input)? If yes, did this work?

Do you own a multimeter?
Can you please carefully open up the SCART plug on your CPC cable and either post a reply giving details of what is connected to where, or if it’s possible, post photos showing us the insides.

Mark
« Last Edit: 12:00, 13 April 20 by 1024MAK »
Looking forward to summer in Somerset :-)

Offline Bryce

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Re: CPC scart cable problem - 1980's CRT
« Reply #9 on: 12:05, 13 April 20 »
It's probably a grounding issue. Make sure that the CPC's ground connection is definitely connected to the TV's ground pins in the SCART connector.

Bryce.