A1200 display has a green tinge - what's wrong?

[dawiper]

Strange. To get colors like that the green component has to be inc. and the blue has to be reduced. They also has to be adjusted equally. Example: 10% more green and 10% less blue.
I just tried adjusting the pictures in a photoprogram.
I think it has to more than a loose pin/cable.

[motorollin]

gizmomelb wrote:
I tried 2 different models of 1084S, a 1960 and my TV with SCART input.  All of them have the green colour.

All of those screens use the Amiga's RGB output don't they? Have you tried using the RF or composite output?

--
moto

[Clooned]

I have a similar problem with my old A1200, all the outputs (RF, SCART and COMP.) are yellow!
Now my A1200 is in a box getting dust because I buyed an A1 but I want to know what is wrong in it.

[alexh]

What do you have inside your Amiga?

Have you tried switching Power Supplies with your mate? A faulty 12v line on your PSU will affect video but not the computer.

Is your SCART cable a TRUE RGB cable or is it a composite SCART cable? (If it connects to the 23-pin connector then it IS RGB).

Try connecting the A1200 to an RGB monitor and to the TV via RF at the same time. You could also try the composite output.

Report back.

I personally think that your video DAC needs to be refluxed. 10 minute job if you're good at soldering.

[gizmomelb]

Hi,

I've removed the Blizzard 1230 from the Amiga, so it's just got the HDD in there.  I've also tried it with 4 different A500 power supplies, so I don't think it's a power issue.

The SCART is an RGB 23 pin cable.  I tried the composite and it also has the yellow video output.  I haven't been able to find an RF cable yet to try.

Hmm, someone at the local user group might be able to resolder the DAC, I personally don't feel confident enough to do it.

Regards,
Gizmomelb

[Tomas]

Does this only happen in Workbench?? Because then it sounds like you have somehow altered the colour slider in preferences  :-P
I wonder this because the early boot menu looks normal?? Or did you use a different a1200 for that?

Is this problem present using both composite out, rgb and rf output?? If so, then it is probably some resistor that is burnt out of one colour, because it seems like one colour is missing, which will give the picture a green tint. If this only happen on rgb output, then it could maybe be a bent pin in the rgb output port??

Edit: I see you have tried most of what i suggested after reading the whole thread... :-P It sounds to me like it is very likely that the problem is a resistor or a burnt out trace on the motherboard since this also happens using composite out. I recall someone having the same problem with an a600, and then it turned out to be a dead resistor.

[gizmomelb]

Hi,

to sum up for everyone - I've tried an RGB-> SCART cable, RGB->DB9 analogue cable and an RGB->VGA (DB15) cable.  I've tried three different monitors as well as composite video output and 4 different power supplies.  The video output to all display devices is yellow (but the mouse pointer is red) if I use workbench, auto-boot games or demo disks (ie: it's not a WB setting).

So I guess if it's a faulty resistor, I should go looking for A1200 schematics so I can figure out which ones to look at with my multimeter, as well as what values they should be.

Thanks!