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Could someone point me in the right direction as how to fix this. It was working fine but now i get a faint picture and lines on the screen.

Kinda just looks detuned - eliminating simple things, you tried retuning the TV? Otherwise, I think I've seen similar when one of the trim pots on the video/power board is set too low (or high, not sure). Can't actually see that on the circuit diagram, I think I assumed it was setting a black level...

Could you please post a picture of your Dragon's motherboard and psu board?

At first sight I'd say you're looking at a NTSC Dragon on a PAL TV.

Here are some pics of the motherboard etc. Plus a picture with the monitor cable in

This is a bit of a long shot, but I once tried to drive a CoCo using a PSU with a lower voltage, which resulted in the screen output being pretty weak (also, it couldn't operate the tape motor).

Perhaps the PSU output voltages should be checked?

Have you tried your Dragon on a different TV? We don't want to 'fix' the Dragon if it turns out that the telly is at fault.

Yep I have tried it on a different TV and still the same. It used to work on this TV.

RV1 the pot just behind the cassette and joystick ports looks very crusty, this could well be the culprit. It would be worth a gentle external clean and then note the position of the pot and give it a rotate back and forth to see if that will clean the contacts enough to improve the output.

Hope that helps, Gareth

Nope that didn't work. Still the same.

If you see it right through the monitor port, maybe you have to adjust the modulator.

I think the two holes in the shiny metal box on the left of the psu board are for adjusting it. Try using a small screwdriver there and see what happens.

You can also open it and take a picture so we can see if any component is damaged.