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Steve1977
9th October 2011, 14:54
I have 2 A1200's and they only produce a picture on a Monitor and with my Phillips monitor packing up and now seeking refuge in the local tip, I wondered if anyone had one they want to sell?

Havent got much funds but desperately need it for the 2011 World Cup of Kick Off 2.

ddni
9th October 2011, 15:03
Why not get an RGB to SCART cable and use any RGB SCART TV?

Steve1977
9th October 2011, 15:15
Ever since resoldering one of the hard drive pins, it does connect to a TV and produces a picture...but it's purple :( You know how on the old monitors you clicked a button to cast a green filter over the image? Well thats what happens but in purple.

ddni
9th October 2011, 15:22
The RGB SCART should carry the same signal that an Amiga Monitor cable would take to your monitor.

Steve1977
10th October 2011, 01:15
Yeah? Very interesting...why does it have a purple overlay? I know sometimes different colours mean different things...do you reckon what might be the problem with this one?

robinsonb5
10th October 2011, 01:31
Yeah? Very interesting...why does it have a purple overlay? I know sometimes different colours mean different things...do you reckon what might be the problem with this one?

What may be causing confusion is that SCART cables can carry the video signal in two ways: RGB (via the Amiga's 23-pin socket) or Composite (via the Amiga's yellow RCA phono socket).

If the picture on your monitor (which uses the RGB signal from the Amiga's 23-pin video port) is OK, then the picture should also be fine on a TV, *provided* that TV also uses the RGB signal from the video port. (Not all TVs support RGB input via SCART, often only one SCART socket has RGB support, and moderns LCD TVs are apparently rather picky about signal levels, mind you.)

My guess is that when the hard-drive pin was resoldered, the trace that carries the green signal to the composite video circuitry was either shorted or cut, and thus no green's making it to the screen when connected via composite (or RF), but direct RGB connections are still OK.

DubbleTrubble
10th October 2011, 03:48
I have 2 A1200's and they only produce a picture on a Monitor and with my Phillips monitor packing up and now seeking refuge in the local tip, I wondered if anyone had one they want to sell?

Havent got much funds but desperately need it for the 2011 World Cup of Kick Off 2.

I've got a Commodore 1942 monitor. It works fine, but has a push switch on the back that has to be forced to stay in with a clip over the plastic switch cover. It can always be disconnected at the mains if you like, though the clip can be swivelled out of the way and the switch can be allowed to move to the off position, it's just the spring ratchet inside the switch that has failed, but the switch contacts work OK.

I can supply an RGB cable if you prefer, and want to use your LCD TV as already suggested, just let me know if you're interested - preferably by PM.

I'm sure from what you've said already, in this thread, that the RGB output is OK for an RGB SCART or RGB video output connector so you decide which way you want to go.

Neil - D.T.

johnim
10th October 2011, 07:22
hi steve

i did not know it was you if you wanted i could pop over one of the nights and have a look at it, did you resolder the earth wire that fell off at the 8bit last month and i still got too give you that 23pin shell for the rgb cable

john

chiark
10th October 2011, 09:06
If it's producing Purple where white should be produced...

R+G+B=white
R+B = purple

It would suggest that the green component is missing to me?

rkauer
10th October 2011, 23:38
You are right.

There a few places to look at: monitor cable (specially where the cable wiggle and on the board contacts).

Second place is the little board attached to the tube's neck. Normally a high wattage resistor or transistor (or both) got burned. 15 minute replacement job.

Last (and worst case) probability the gain controller chip in the board got fried (depending what monitor you have).