TG16 - Black/purple screen at boot. Composite not RF.

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nova1313
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TG16 - Black/purple screen at boot. Composite not RF.

Post by nova1313 »

TG-16 with no game in, the video signal shows a solid purple/pink screen. With a game in the screen is solid black.

I added composite to check if it was RF port. Same thing.

Recapped most of the system but I didn't have the caps for the following:
C101 22uf 16v
C129 100uf 25v
C132 100uf 16v
C140 47uf 16v
C1 22uf 25v

I plan to do them later. None of them look bad.

Cleaned the hu card slot pins and polished them a bit. Cleaned the hu cards.

Checked the voltage on the power supply and it is suspect. It should be 10.5v but when I plug my meter in it is showing 15 with no load.

Any ideas on what else I should check?
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Hobie-wan
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by Hobie-wan »

Back the carts out as far as you can where the lock will still go to turn the power on. It is pretty common that some will push in a little too far and then it is likely that one of the pins isn't connected anymore and you end up with a solid screen of a seemingly random color. Hopefully that's your issue too.
nova1313
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by nova1313 »

No luck. Any idea if it is safe to go in and bend the pins up a little? Do they give at all? I haven't tried.
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by Hobie-wan »

You did clean the cards and the system pins too, right? Never heard of anyone needing to bend the pins on a TG, but I suppose it is possible if you look in there and don't see them all hanging down evenly.
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by nova1313 »

They are all hanging evenly. I can't find a way to bend them. The plastic shroud blocks it.

I put a coffee filter over a hucard and ran that in and out of the system with some alcohol on it. Didn't come out looking dirty. Did this maybe 20-30 times.

Took an eraser and alcohol rub to the hucards also. They look excellent.

Just tried to reflow the solder on the card connector also.

still:
No card in - purple/pink screen.
Card in - sometimes black screen sometimes purple/pink. One card gave me a white screen but only once.

I tried backing out the cards slightly like suggested. It seems if the card is all the way in I get a black screen, any amount out I'm getting purple.
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Hobie-wan
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by Hobie-wan »

Any bad looking capacitors on the boards? I'm not sure what else to suggest. :(
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by nova1313 »

Caps all look fine. I had replaced some (but they didn't look bad). the remaining I don't have caps for. I could order them and replace the remaining 5 or so.

I tried a known working SMS power supply today for fear the Turbo power supply was bad. That didn't fix it.

If you think of anything else let me know. Thanks for your help!
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ApolloBoy
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by ApolloBoy »

Try checking some of the traces around the HuCard slot.
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nova1313
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by nova1313 »

Sorry it took me so long to get back to this. I finished recapping the remaining caps. Didn't work.

I reflowed all the connections on the board. Didn't work.

Cleaned the hucard slot again. Didn't work.

Removed RF board (looked bad/sloppy). Didn't work.

I've checked that all the pins on the hucard slot reach the board.

So for now I think it is done.
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Re: TG16 - Black/purple screen at boot. Composite not RF.

Post by ApolloBoy »

Have you tried checking the 7805 regulator yet?
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