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1975 PYE CT-219 “Chelsea” 717 Chassis

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Nuvistor
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Through the 70’s the sets with the best EHT stability never compared with a well set up PD500/GY501 shunt stabiliser/EHT rectifier. 

Those included the solid state sets from RBM, Philips, ITT, all excellent but not quite there. In fact with one customer who had a dual standard set with the shunt stabiliser and wanted to replace the set , we had to take a few sets to his house before he was reasonably happy with picture size stability compared to his old set. These sets were properly set up so giving their best.

I think the introduction of the diode split LOPTX improved the situation by the later 70’s.

Again all recollections for many years ago and time plays tricks on memory, well it does on mine. 

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Posted : 04/02/2021 10:03 am
Cathovisor
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Posted by: @nuvistor

Through the 70’s the sets with the best EHT stability never compared with a well set up PD500/GY501 shunt stabiliser/EHT rectifier. 

Those included the solid state sets from RBM, Philips, ITT, all excellent but not quite there. In fact with one customer who had a dual standard set with the shunt stabiliser and wanted to replace the set , we had to take a few sets to his house before he was reasonably happy with picture size stability compared to his old set. These sets were properly set up so giving their best.

I think the introduction of the diode split LOPTX improved the situation by the later 70’s.

Again all recollections for many years ago and time plays tricks on memory, well it does on mine. 

I think the B&O that Chris owns would shame all of those. In my old field the best monitors for EHT stability were the Barco CTVM3 family, which had a separate EHT generator.

 

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Posted : 04/02/2021 11:53 am
Nuvistor
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@cathovisor

I never had dealings with B&O but know they had some excellent performances.

Yes specialist monitors in general had much better performance all round.

Well I am off for COVID vaccine jab now so we will how that pans out.

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Posted : 04/02/2021 11:59 am
Cathovisor
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Posted by: @nuvistor

@cathovisor

I never had dealings with B&O but know they had some excellent performances.

Yes specialist monitors in general had much better performance all round.

Well I am off for COVID vaccine jab now so we will how that pans out.

Good luck with your jab, Frank.

The B&O set Chris has is built along professional lines in that it too has a separate EHT generator and many other features.

 

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Posted : 04/02/2021 12:06 pm
crustytv
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Suitably rested after the 6-month battle with the G6, what do I go and do? Am I barking mad?

I decided to tackle the PYE CT-219, this little TV came from the same location as the G6, it was a couple of feet away from the G6 in the Barn I visited. Outwardly it looks fairly good, it brushed up well, inside? Well, it's not too bad, The tuner/IF panel looks in good condition, the tuner unit a tad rusty. CRT base good, Chroma panel good, convergence panel good but many of the pots have surface rust, we'll have to see how they fare inside. The PSU/timebase panel is all there, but looks grotty. This will be given a thorough treatment of PCB cleaner.

Before any power is applied, the PSU will be checked over and the green meanines removed (mains filter & flyback tuning). Then we shall see if this turns out to ber yet another basket-case!

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Topic starter Posted : 16/07/2021 11:21 am
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Cathovisor
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Nice-looking little set, Chris - good luck with it 🙂 

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Posted : 16/07/2021 11:40 am
Red_to_Black
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That looks to be in much better condition than the last few I saw back in the late 80's 👍 

The firm I then worked for had just taken over another shop with rental customers that we didn't want, or need, anyway in the rental stock pile was about three of these sets amongst other old models of course, these must have had a very hard life though, crispy circuit boards, convergence controls properly cooked and seized solid, two of them had had major burnups in the past and had been patched up, of course all three crts were as flat as a witches proverbial.

My then boss took one look and immediately ordered them scrapped! Yours looks positively new by comparison. 😊 

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Posted : 16/07/2021 12:52 pm
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PYE625
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I'll stick my neck out and say that should work with the minimum of fuss. Nice smart looking set.

 

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Posted : 16/07/2021 2:20 pm
crustytv
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Hi Baz, it's quite remarkable the sheer variety of sets you've had the pleasure, or should that be displeasure of, to pass before your bench. I guess that's the benefit of working for an independent. Must have made for a very interesting career, rather than being stuck/tied to a couple of brands.

I've mostly found whenever this TV is mentioned, the resulting shrieks of horror are not too far behind, with many tales of how appalling they were. I guess it met the market need like the Thorn 8000, a budget colour TV that enabled the masses to get on board with colour.

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Topic starter Posted : 16/07/2021 2:20 pm
crustytv
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The PSU/Timebase PCB was given a thorough cleaning and left to dry out in the intense heat outside, it didn't take long to dry. Looking at the print side of the PCB, it would appear to not had any work in the past. There does seem some evidence above board with one wigwam repair.

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Topic starter Posted : 16/07/2021 3:13 pm
crustytv
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The boards once cleaned reveal they are in remarkable condition. The only work I can see that's been carried out is on the Chroma panel, unsurprisingly the thick film unit. I wonder if this is a low hour set, and if so why? The CRT tested VERY good, am I going to find its low hour due to some obscure fault, I always seem to attract the sets with problems.

Chroma

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All the boards

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Topic starter Posted : 16/07/2021 3:30 pm
Red_to_Black
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Posted by: @crustytv

Hi Baz, it's quite remarkable the sheer variety of sets you've had the pleasure, or should that be displeasure of, to pass before your bench. I guess that's the benefit of working for an independent. Must have made for a very interesting career, rather than being stuck/tied to a couple of brands.

It was both a blessing and a curse  🤒 , on the plus side two days were never the same, on the downside we were often faced with sets that we we were not familiar with.

These sets were old even then and before my time, my then Boss even stopped us repairing the 9K series at this point, unless it was a quick fix, TX9 and 10 only or later!, this was a business decision btw!

As independents every set that came in was an 'earner' so we had to get to grips toot sweet and maintain turnover!, note: not profit, but turnover! This was mainly a sales driven outlet btw, of course we would take in outside repairs too.

This actually backfired! as he hit the Vat threshold and ended up bankrupt!, which was a shame as he was a decent bloke.

I next worked for a 'sole trader' again a decent bloke, I had already had warned about the previous, but again this was a sales driven venture, and again it ended in tears!

By this time there wasn't enough work for full time engineers! so I consequently worked for three different shops on an alternating days basis, thankfully two of them were only mainly repair shops rather than sales driven. Of course they still sold a few sets, but mainly repair places, this is where I really learned 'the trade' !

Good times indeed!

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Posted : 16/07/2021 3:47 pm
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Red_to_Black
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On a side note to the above ^^^ I was asked to work for one or two cowboys, these people offered me nearly double my wages! at the time, these were the type that would 'offer' two year guarantees with black fablon covered TX9/10s delivered in a taxi !, never to be seen again!, I did repair one or two of these sets for them, mainly to stop them from getting a "good kicking" from some of their more 'salubrious' customers 😉 

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Posted : 16/07/2021 4:12 pm
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Jayceebee
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Posted by: @crustytv

There does seem some evidence above board with one wigwam repair.

I could be wrong but looking at the board markings and components used I suspect it may be original.

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Posted : 16/07/2021 10:21 pm
crustytv
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Posted by: @jayceebee

I could be wrong but looking at the board markings and components used I suspect it may be original.

I know this was a budget set John, but I doubt even PYE/Philips would stoop so low to manufacture 3 resistors in series when one would suffice.

No, on this occasion, I'm afraid you're mistaken. The 3 series 150K resistors are a bodge for R531 which should be a 470K. They'll be removed and a 470K added. I suspect it was an urgent or last field repair that got the set going, and it was never returned to change.

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Topic starter Posted : 16/07/2021 10:43 pm
Red_to_Black
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I wouldn't be so sure Chris! PYE did a lot of things that shall we say was "unorthodox" 😉 

I look forward to see how you get on with this 👍 

Ps. it does look like someone made a tv set out of the G11 parts bin and threw them in a washing machine! although this set used earlier technology than the G11 😎 

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Posted : 16/07/2021 11:30 pm
crustytv
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Posted by: @red_to_black

I wouldn't be so sure Chris! PYE did a lot of things that shall we say was "unorthodox"

Well, all I can say is the wigwam is not original, I'll scan the cct tomorrow, maybe that will satisfy 👍 

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Topic starter Posted : 16/07/2021 11:44 pm
crustytv
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Mentioned many times before, but worth going over for anyone new looking in. Some may bother with this, some may not, each to their own. I always reform the main reservoir caps, I don't like brute forcing them, especially if they're faulty.

The combined multi-can reservoir caps 535/536 600uF/250uf have been removed and is currently reforming. This allows me to supply rated voltage from 0-500 if required in controlled steps. The neon indicator is struck all the time there is leakage, when it extinguishes, leakage has ceased, you can then move onto the next voltage step all the way up to max rated +10%. I connect two meters so I can monitor current and voltage attained.Good caps reform very quickly, some take a few hours and some fail, resulting in replacement.⁠ This one is taking its time.

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Topic starter Posted : 17/07/2021 8:44 am
crustytv
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First section successfully reformed, no leakage.

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Topic starter Posted : 17/07/2021 10:06 am
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PYE625
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Doing some groundwork first pay's dividends.

Why take the risk with often hard to get components?

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Posted : 17/07/2021 10:50 am
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