Is my A1200 b0rked? (Issue w. Sony LCD)

[Nostalgia]

HALP!
 
Sorry about the wall 'o text below, but this really is driving me up the, well - wall.
 
I recently (yesterday, in fact) took delivery of a refurbished A1200 (4GB Flashdisk) from Amigakit. I set it up, RGB to new-ish Sony LCD, and got WB 3.1 installed. All was well - picture looked nice and clear - and I went to get some dinner.
 
10 minutes later I return to the livingroom, and find the screen filled with a black/grey blur - looked like a disconnected cable, but after checking all connections and finding no issues, I tried rebooting. This immediately solved the issue, as the A1200 booted to the WB with no problems.
 
This time I tried staying with the Amiga, watching the screen, and was treated to the same phenomenon: after about 15 minutes the picture started shifting sideways, accelerating until it was nothing but a mass of black with some grey streaks. Instead of restarting, I gently unplugged the RGB from the telly and then re-inserted it - this brought the picture back to normal - for 19 minutes.
 
Since then I've tried leaving the A1200 on and off for a few hours, and the pattern is the same each time: 10-15 minutes of both WB-inactivity and me jiggling the mouse about, and then black screen of death.
 
This is what I know so far:
 
1. A reboot fixes the picture immediately - no need for the Amiga to "cool down"
 
2. Resolution has nothing to do with it - I've tried all res's from 640*512 interlaced to 1280*256 de-interlaced
 
3. It doesn't matter if I use the Amiga or not - it "crashes" anyway
 
4. Two times it has crashed *just* as I jiggled the mouse - although that may have been a simple coincidence
 
5. I'm currently testing it with the RF-cable - hasn't crashed yet (45 mins in)
 
I'm pretty gutted at this, as I'd really been looking forward to playing all my old games again. The Amigakit-bloke seemed quite forthcoming, and I'm sure he'll replace my current A1200 if need be, but I'd really appreciate your thoughts on this all the same.
 
Thanks in advance.
 
Andreas

[dangermouse]

Have you tried power cycling your LCD on/off when it does it? Does that 'fix' the issue also?

If you can reinsert the RGB cable and it fixes the problem sounds more like an LCD issue than an Amiga issue. Have you got a scandoubler in your setup somewhere or does your LCD sync to Amiga screenmodes natively? I'm not an expert by any means but it sounds like your LCD loses sync with the Amiga after a certain period of time although why that may be is beyond my knowledge. Reinserting the RGB cable sounds like it's causing the LCD to re-sync successfully again.

Have you got another Amiga you can try on the same LCD? That may point the finger in the appropriate direction more accurately.

[tone007]

I'd have to try with a different monitor (RGB preferably, but even just composite is worth a shot) and see if you get the same issues.

Also, you mentioned trying with different resolutions, was one of the ones you tried Multisync mode? (640x480@31.5Khz I believe.)

edit: above suggestion (monitor power cycle) is a very good one too.

[the_leander]

Could be some dodgy soldering on the RGB connector, or dirty contacts, or even something broke in transit...

This is the problem when you're dealing with 16+ year old hardware.

I'd try plugging in the RGB connector one last time, see if jiggling it again causes it to crash again. At least that narrows this list of possibles down.

[tone007]

Instead of restarting, I gently unplugged the RGB from the telly and then re-inserted it - this brought the picture back to normal - for 19 minutes.

Re-reading, this would lead me to blame the TV.

[Nostalgia]

Cheers guys - the missus is hogging the telly tonight, so further testing will have to wait 'till tomorrow. I'm sorta hoping it's the telly, as I'm looking to buy a new one soon-ish - although the best outcome would obviously be that it just... worked.

[Nostalgia]

Right - tried powercycling my TV, and that brought back the picture just fine. Looks like it IS the sync-issue then - but is this fixable, and if so how?

[tone007]

If a non-15Khz mode (like "Multisync" mode) is stable on the TV, you could probably get away with an Indivision once they come out with another batch, or you could try composite if your TV has the jack for it, awful for Workbench of course but for gaming it could get you through until a new TV comes along.  There also have been affordable S-Video adapters if that's an option on your TV.

[Nostalgia]

If a non-15Khz mode (like "Multisync" mode) is stable on the TV, you could probably get away with an Indivision once they come out with another batch, or you could try composite if your TV has the jack for it, awful for Workbench of course but for gaming it could get you through until a new TV comes along. There also have been affordable S-Video adapters if that's an option on your TV.

How does composite compare to RGB for gaming? WB isn't much of an issue, as I'll mainly be using it for accessing WHD Load.
 
It's really strange, because a friend of mine has just tested his A1200 with his Sony (different model, though) and it seems to work just fine.

[tone007]

You lose some quality with composite (color, sharpness,) but alot depends on how well your TV does composite.  For games, personally I could be happy with it if it were my only option.

[the_leander]

How does composite compare to RGB for gaming? WB isn't much of an issue, as I'll mainly be using it for accessing WHD Load.
 
It's really strange, because a friend of mine has just tested his A1200 with his Sony (different model, though) and it seems to work just fine.

Just a thought, perhaps you should take your 1200 over to your friends house and see if yours works on his set.

The reason I say this is because I don't want you to go out and buy a new TV, only to find that actually, the fault was on the 1200 afteral.

[Nostalgia]

Just a thought, perhaps you should take your 1200 over to your friends house and see if yours works on his set.
 
The reason I say this is because I don't want you to go out and buy a new TV, only to find that actually, the fault was on the 1200 afteral.

Yeah - I'll probably do this one of these days as well.
 
EDIT: What are odds that it IS the Amiga, do you think? Bearing in mind the powercycle-fix and no issues whatsoever with RF?

[amigakit]

And we soak test every A1200 for about two days before shipping to customers.  As part of our Quality Control, we have structured Pre Delivery Inspection tests that include testing for many hours on both RGB video and Composite.

[the_leander]

Yeah - I'll probably do this one of these days as well.
 
EDIT: What are odds that it IS the Amiga, do you think? Bearing in mind the powercycle-fix and no issues whatsoever with RF?

16-18 year old kit verses 2 year old gear. It might be that the timings a little tighter on the newer gear than the Amiga, it might be that something shook loose during transit.

No bad on amikit, from what I can tell they're a bang up service. But as kit gets older it gets more fragile.

Best to test it against your mates telly before either sending it back or getting a new telly yourself. It just means you've ruled out everything else before blowing cash.

[Nostalgia]

And we soak test every A1200 for about two days before shipping to customers. As part of our Quality Control, we have structured Pre Delivery Inspection tests that include testing for many hours on both RGB video and Composite.

So you tested it with RGB, then? Of course the broke-in-transit-option remains, but the package looked in pretty good condition when it arrived. I'll test it on my friend's Sony next (or possibly this Saturday), and if it works then at least I know that the issue is with my TV (or my TV and the A1200).