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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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22nd Apr 2021, 9:14 pm | #21 |
Hexode
Join Date: Nov 2010
Location: Sheffield, South Yorkshire, UK.
Posts: 278
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Re: Philips 22cs1002
Not a TV engineer by any stretch, but it looks like the type of fault that occurs on a modern LCD type display, like poor edge connectors on the panel, very odd..
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23rd Apr 2021, 1:08 am | #22 |
Octode
Join Date: Jun 2018
Location: Essex, UK.
Posts: 1,307
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Re: Philips 22cs1002
I have no idea about anything about these sets, so i may be way out here, but if it does have a tuning indicator, could it possibly be that the circuitry is playing up a bit and trying to generate a line of some sorts?
I'll be following this thread with interest as I do quite like these sets Good luck with it '77 |
23rd Apr 2021, 7:24 am | #23 |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,571
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Re: Philips 22cs1002
The TV does not have an auto tuning band. I still think it's a decoupling problem. I think it's non-remote with manual tuning. 30 years since I've seen one of these.....
If it was mine I would have scoped the supply rails by now.......
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23rd Apr 2021, 8:26 am | #24 | |
Octode
Join Date: Apr 2016
Location: Ventnor, Isle of Wight, & Great Dunmow, Essex, UK.
Posts: 1,377
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Re: Philips 22cs1002
Quote:
My first thought when I saw the fault was decoupling to the RGB output stages. Even though it looks a little different to how that fault normally looks and the line is very narrow, the picture disturbance is still happening at line rate. Therefore it's most likely to be line rate hash on one or more supply rails that are derived from the line output stage. The other possibility is pick up from the line stage by the leads going to the tube base PCB. Less likely I know on a modern TV rather than a valve line O/P stage, but still theoretically possible. Will be interested to see what it turns out to be! Reminds me of the monthly 'test case' in 'Television' magazine! Cheers Nick |
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23rd Apr 2021, 10:53 am | #25 |
Dekatron
Join Date: Aug 2006
Location: Madrid, Spain / Wirral, UK
Posts: 7,498
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Re: Philips 22cs1002
I recall a similar fault but with horizontal stripes and other odd symptoms that affected patches of the raster in a CTX set of similar vintage. That was solved by resoldering dry joints around the chroma circuit.
Never seen anything like this though.
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23rd Apr 2021, 1:18 pm | #26 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,199
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Re: Philips 22cs1002
Doesn't the colour decoder use one or more horizontal deflection derived signals for timing? A sandcastle pulse maybe? Might be something wrong there. In any case, the fault seems to be coupled to the horizontal defelection. Could also be some kind of ripple on a horizontal derived supply line.
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23rd Apr 2021, 1:58 pm | #27 |
Heptode
Join Date: May 2006
Location: Accrington, Lancashire, UK.
Posts: 978
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Re: Philips 22cs1002
This is possibly a rare case of Barkenhausen. Does the line remain stationary as you tune the tv throughout the UHF band.
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23rd Apr 2021, 7:29 pm | #28 |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,571
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Re: Philips 22cs1002
...Which is exactly what I was suggesting when I suggested starting with the 4.7uF decoupler on the 155V rail back in post 17. It's line derived and probably has lots of line-rate spikes on it that shouldn't be there......
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There are lots of brilliant keyboard players and then there is Rick Wakeman..... |
24th Apr 2021, 9:05 am | #29 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,199
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Re: Philips 22cs1002
I was thinking more along the lines of a low voltage supply line to the decoder, but could be.
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24th Apr 2021, 8:53 pm | #30 |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,571
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Re: Philips 22cs1002
Yes...that is why I said to 'start with' the RGB decoupler. It could well be a supply to the decoder also.
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There are lots of brilliant keyboard players and then there is Rick Wakeman..... |
25th Apr 2021, 11:00 am | #31 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,199
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Re: Philips 22cs1002
Ah yes, I must have missed or forgot the "also try ..." part of your message. Sorry.
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28th Apr 2021, 7:36 pm | #32 |
Pentode
Join Date: Mar 2009
Location: Norwich, Norfolk, UK.
Posts: 228
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Re: Philips 22cs1002
Hi folks. As this set only lives 25 miles away, I offered to have a look at it as it looked like an interesting fault. Anyway it arrived this morning and is now sorted. Annoyingly I have not got a K30 or a manual and worse still, I seem to have lost my 1981/1982 Newenes book.
The set turned out to be a lovely low usage set with a good CRT. I could not see any evidence of a repair, not even the 4.7ohm surge limiter had been replaced. Not bad for a 40 year old set. I remember seeing these when they first came out at a London trade show in one of the big hotels they used to use. We were Pye dealers back then so stocked the Pye version, which in my opinion was the better looking, set. Back in the day they were one of the best for reliability, just let down by short CRT life sadly. First thing I did was remove the “IF” module, the line was still there so that had eliminated the “IF” and tuner. Next I scoped around the TDA3560 and the Sandcastle pulse, even though it was there and reasonable amplitude did not look right. This pulse is generated in the TDA2571AQ line osc. chip. Luckily I had a new one in stock and it cured the problem line. So a happy ending for a very nice set. Cheers David. |
28th Apr 2021, 8:13 pm | #33 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,844
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Re: Philips 22cs1002
Well done David!
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28th Apr 2021, 8:34 pm | #34 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,918
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Re: Philips 22cs1002
We can all sleep soundly now - odd how these faults still turn up to perplex us all even when we thought we knew the sets inside out!
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29th Apr 2021, 1:28 pm | #35 |
Triode
Join Date: Nov 2011
Location: Lowestoft, Suffolk, UK.
Posts: 34
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Re: Philips 22cs1002
The tv is back home with me now all looking great and working fine, turns out it was the tda2571aq chip on the line oscillator module, thankyou so much for everyone's help much appreciated
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29th Apr 2021, 1:30 pm | #36 |
Triode
Join Date: Nov 2011
Location: Lowestoft, Suffolk, UK.
Posts: 34
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Re: Philips 22cs1002
Many thanks to David
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29th Apr 2021, 1:31 pm | #37 |
Triode
Join Date: Nov 2011
Location: Lowestoft, Suffolk, UK.
Posts: 34
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Re: Philips 22cs1002
Moderators please close thread
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