Display issue

A place to discuss everything Dragon related that doesn't fall into the other categories.
mustangus
Posts: 6
Joined: Sat Jul 01, 2017 1:28 am

Re: Display issue

Post by mustangus »

I get like scanlines and a faint bar scrolling down the screen on the monitor port and not the clear solid green and black text. The modulator output is worse than the monitor screen.
sixxie
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Joined: Fri Jul 18, 2008 8:36 am
Location: Hertfordshire
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Re: Display issue

Post by sixxie »

Tried reseating the PSU board connector (the chunky one that links it to the motherboard)? I find that sometimes helps with video issues. Think the pins oxidise and a bit of mechanical action helps scrub them.
tjewell
Posts: 346
Joined: Mon Oct 19, 2009 4:58 pm
Location: Cambridge, England

Re: Display issue

Post by tjewell »

It's also worth noting that you have an earlyish D32 (the daughter board for the ram is a clue), so the quality of the video will never be that good, sadly. I have a D32 of that vintage and the quality is noticeably worse than my more recent D32, and my D64 is almost acceptable! So I wouldn't strive for perfection - but equally, that first picture of the RF signal is very poor, I'd expect it to look more like that picture of the monitor output. Good luck!

Tony
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robcfg
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Re: Display issue

Post by robcfg »

That's right!

There were some models (16 x 16K MKII board, PC10087 Issue 6 P/N 48127 ) released with a P/N 48200 daughterboard to improve the signal quality.

It was later added to the Dragon 64 board.
Alastair
Posts: 669
Joined: Fri Jul 18, 2008 11:33 pm

Re: Display issue

Post by Alastair »

munkeyboy wrote: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
MustAngus, even though it looks fine in the photo it may also be worth doing the above with RV2.

Another thing you may wish to do is remove both boards and check the underneaths for suspect solder joints or traces.
mustangus
Posts: 6
Joined: Sat Jul 01, 2017 1:28 am

Re: Display issue

Post by mustangus »

I'll have a look underneath later. For the quality of the pic it was perfect before and on the same tv so i know something is queit right. Not sure whats going on with my other dragon 32, i have sound but no pic (i'll tackle that one much latewr thou.)
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