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Old 7th Aug 2022, 9:36 pm   #15
19Seventy7
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Join Date: Jun 2018
Location: Essex, UK.
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Default Re: Thorn 3000 - flywheel test point

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Originally Posted by its ur aerial View Post
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Originally Posted by 19Seventy7 View Post
Hi all

. The Thorn 1500 has a dead IF stage, looking like VT7 is faulty, but I digress.
Its a long time ago, but VT7 rings a bell

As for the uncontrollable brilliance etc, there's a set up procedure involving the set white switch and at least two presets, I think one is in the Frame Board, cant remember now once done they can produce a half decent picture, not sure if a Thorn New Life CRT is much of a positive They had a poor reputation back in the day.
As for the loss of Video, check the Decoder PCB, if it is fitted with the Thick Film Video out put module, they were notorious for intermittent faults, such as blank white raster, smearing etc etc.
Ken G6HZG.
I have to admit I cheated a little and googled the fault, and found that there was a fairly extensive thread on the same fault, I did all the same checks on "my" set and found VT7 to be well out of spec.

I think you're dead on with the thick film module too, it will just fade into a pure white raster and the video is pretty smeary, but I originally put that down to being from VHS, when it did the same from DVD I realised it was the TV at fault, I've got some 12k and 56k resistors on order to replace that with. Being it'll be a somewhat daily runner I think it'd be good practice anyway just for the sake of reliability.

Thanks for the heads-up on that one, as I don't think I'd have suspected the module to cause that

Thanks
'77
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