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-   -   Philips 22CS1002/05t TV (https://www.vintage-radio.net/forum/showthread.php?t=162296)

Eidolon 19th Dec 2019 11:28 pm

Philips 22CS1002/05t TV
 
https://www.vintage-radio.net/forum/...newthread&f=37

Just returning to this after a while. I SENT it in for a fix with someone else and it's come back a lot better, but with some differences, and questions.

He modded channels 5-7 into video channels, which I'm pleased about, ut there's a noticeable difference, which the native Channel 8 vcr channel ow also has. Previously when using the dedicated vcr channel, there were visible scan linez, as if it was deinterlaced. This is no longer present. Was the previous appearance a fault?

He's. Made some changes to the guns. He said it was unfixable as the tube was dying. He could short something out to get it working, but that would kill it all the more quicker. Nontheless, he got the 40 minute warm up time down to 20 mins, but I'm not overly keen on the change in picture quality. There is now a quite noticeable blue tinge to everything. When watching something in monochrome it's now blue and white, and turning the colour to minimum doesn't make any difference. Previously monochrome was ok unless there was lots of white, at which point it would temporarily tint red.

Any ideas if there's any way to fix this blue tinge and the warm up? Just asking in case anyone has any extra ideas. Thanks.

Red to black 19th Dec 2019 11:45 pm

Re: Philips 22CS1002/05t TV
 
Do you mean this thread ?

https://vintage-radio.net/forum/showthread.php?t=110106

ben 20th Dec 2019 1:21 am

Re: Philips 22CS1002/05t TV
 
Did the RGB cap ever get changed?

ALso, when you say warm up time, do you mean that no picture appears for 20 mins?

rambo1152 20th Dec 2019 1:36 am

Re: Philips 22CS1002/05t TV
 
1 Attachment(s)
It very much sounds like he's done his best with a tube that has low emission on one or more guns.
If you want to try setting the greyscale up yourself, refer to the attached image.

Use an appropriate sized flat bladed screwdriver with an insulated handle.

Turn the colour down to zero to give a monochrome picture

The three potentiometers with circles adjust the overall brightness of the corresponding colour. Endeavour to remove any tint in the darkest parts of the picture.

The three pots marked with squares do much the same but affect the highlights to a greater degree, so use them to remove colour tints in the bright parts of the picture.

Maybe you can obtain a result that is subjectively more pleasing, but it sounds like the CRT is well past its best.

Maarten 20th Dec 2019 2:30 am

Re: Philips 22CS1002/05t TV
 
While shorting out the coil or resistor in the CRT heater circuit permanently will shorten the tube life, it could be worth the gamble to try and heat the tube at 8 to 12V for a few minutes or hook it up to a regenrator. 30AX tubes may respond well to it and you have nothing to lose at this point.

Eidolon 20th Dec 2019 10:35 am

Re: Philips 22CS1002/05t TV
 
It starts black, and then slowly warms up to visible.

But I'm sure the picture quality doesn't look as good, colour tint or not. I'm not quite sure how to describe it really, a bit murkier with a bit on an ntsc to pal video kind of look maybe. Softer. There's definitely problems with the colour that it didn't have before, things often look kind of gaudy. I'm not sure if he changed the rgb caps, he didn't say anything about it.
I'm still a bit unsure as to why the normal and video channels both now look the same.

I also hax some problems with vertical lines on the screen. He used a replacement part that a member here sent me to try and fix it, and that got rid of all but the biggest line, but after using the set for a couple of hours, two other lines have now appeared on screen. Worse than before.

Welsh Anorak 20th Dec 2019 10:37 am

Re: Philips 22CS1002/05t TV
 
The K30 was a great set but was unkind to its tube. The A56-540X was used in many sets of the period, however, and the longevity was mixed. So maybe you can still find a good one in a Sanyo 5133, an Amstrad 2200 or a TX100, as these were kinder to their tubes in my experience. If you can find someone with a BK rejuvenator or similar I've found that they respond quite well. Sounds like your repairer was understandably reluctant to short out the coils on the CRT base but, as Maarten says, you've nothing to lose.
PS Make sure the RGB HT decoupling cap's been changed as Ben says - ISTR it was increased in value from 4.7 to 22uF but I might be wrong on this.

slidertogrid 20th Dec 2019 11:30 am

Re: Philips 22CS1002/05t TV
 
I had lots of these sets out on rental because they were so reliable we ran them into the ground . Their swansong was to be used as loan sets often with a heater coil shorted to bring tube emission up.
When the tube got really bad the set was finally scrapped by then both coils had been shorted. it was surprising how long they would carry on like that.
In all that time I never came across a tube that was so bad it took a long time to show a picture.
Unless someone has boosted it to death ?
Is it possible to ask the person that serviced the set what was done? is the tube low emission? did he short a coil or both and did he change the A1 capacitor?

otherwise can you take a few pictures? A picture of the picture as displayed on the screen, a picture of the tube base front and back and a picture of the top of the chassis/pcb around the A! controls component side should answer the questions as to what was done.

If both coils are shorted out and the emission is still poor there is not a lot of hope for the tube, if overrunning the heaters doesn't improve the picture I doubt boosting it will. I always found boosting in line gun tubes was a waste of time. Overrunning the heaters slightly was a much longer term cure. We called it the Heater Modge.
Often a tube's life could be extended for a couple of years in this way.
Rich

Eidolon 20th Dec 2019 12:00 pm

Re: Philips 22CS1002/05t TV
 
It may well have 'been boosted to death' actually. The local repair 'expert', who wrote off my ITT v2000 machind after putting it back together wrong came round a couple of years or so ago, when it was taking about 5 minutes to warm hp, and some tinkering in the back, soldering and turning things.
It fixed the warm up problem for a couple of months, then it started to come back and got much worse, now taking about 40 mins to warm up.

I just can't get on with the picture anymore, since the new fix, and i think it's because of the blue nature of the monochrome. I didn't have this problem beflre, the blacks were fine. Having been using it a bit now, i think that the 'monochrome blue' is why it looks so bad. Previously the picture was pretty much fine, once it hax warmed up, other than going red when it had a lot of bright white on screen.

Thanks for the list of compatible tubes. Its a matter of trying to find one. I'm fairly sure I'll need to replace it if possible

Eidolon 20th Dec 2019 12:04 pm

Re: Philips 22CS1002/05t TV
 
Quote:

Originally Posted by Red to black (Post 1200620)

Yes thanks, and another one after it. I seem to have bodged my original link. They've changed the browser layiut and workings on my phone, and I'm still trying to get to grips with how it works.

Welsh Anorak 20th Dec 2019 3:59 pm

Re: Philips 22CS1002/05t TV
 
Graham in post 4 has very helpfully labelled the background controls (uppermost three). It's simply a question of finding an insulated screwdriver to fit, letting the TV warm up, turning the colour down to zero abnd the brightness down a little, then backing off the blue background control a little to get a reasonable monochrome picture - use a mirror. Slightly to the left of the photo are the drive controls which might need a tweak to balance the highlights - increase the brightness control for this.
However it's pretty likely the tube is beyond any help. However - and this is important - check whether the two coils are present on the CRT base, even if they're shorted out. They'll need to be re-instated if you're lucky enough to get a replacement tube. There are two on the CRT base, represented by a curly line, and also two on the main chassis to the left of the LOPT.
Try a wanted post - you never know! A56-540X is the CRT you need.

Heatercathodeshort 20th Dec 2019 5:19 pm

Re: Philips 22CS1002/05t TV
 
The early 30AX tubes suffered from a very short life. Mullard sorted the problem turning into one of the very best colour tubes of all time.
It's fat neck demanded high scanning currents but the focus was pin sharp.

I hope you can improve your 'grey scale' a bit but it appears your tube is near it's end. If you can get a replacement it takes only minutes to fit with just the grey scale to adjust. I hope you get it sorted. The K30 is an excellent receiver. John.

Eidolon 14th Feb 2020 1:21 pm

Re: Philips 22CS1002/05t TV
 
How do I adjust the overscan/geometry myself please? I know there are a few things to turn in the back of the set but am not sure what to do.

Also, how would I be best going about doing a listing looking for a replacement tube? I'm not really sure how best to 'advertise' it given that there are a number of compatible tubes. In relation to that, I know the set has been over-boosted, and that's what's caused it to take so long to warm up. If I do find a replacement tube, do I need to do something inside the set to remove the boost that's been applied so it doesn't affect the new tube?
Thanks :)

Welsh Anorak 14th Feb 2020 2:08 pm

Re: Philips 22CS1002/05t TV
 
To answer your questions:
A manual would be helpful to pinpoint the geometry presets - maybe someone has a scan they could attach? If not I should be able to find one for you.
Your tube is an A56-540X. As John says, these were excellent tubes picture-wise, but the early ones died very quickly. Later ones were pretty long lived. Unfortunately there's no easy way of telling which you're getting, though I'm sure Maarten would be able to give you some pointers. As a rule, the ones fitted to later receivers such as the Philips K40 and 2A were good, but as these were good receivers are hard to find. The Amstrad 2200 was a terrible set and so was a good tube donor, but finding one will be a challenge. Thorn TX100s tended to have good tubes, but the TX10 didn't. I'd just put up a 'wanted' request and see what happens.
Yes. you will need to 'unmodify' the boost that's probably been applied. There should be two coils on the tube base and two on the main chassis, all in series with pins 1 and 14 which are the CRT heaters. These may be present and shorted out or missing and linked over. It's vital they are re-instated or else a replacement tube will have a very short life.

Maarten 14th Feb 2020 2:47 pm

Re: Philips 22CS1002/05t TV
 
The date code is usually the last part of the second line in the white stamp on the bell of the tube, so that would indeed be a way to tell if it's a later one though I'm not sure from which year on they were more reliable. I'm guessing some time around 1984 if this coincides with the K40 chassis. In that case it's easy: By that time they were already stamping two digit years, so 84 for 1984, etc.

The revision is also in the same stamped code, but same problem: I don't know which revision is best.

There might also be unknown differences between factories.

Heatercathodeshort 15th Feb 2020 11:57 am

Re: Philips 22CS1002/05t TV
 
The Philips 22CS1002 employed one of the early short life 30AX tubes. I well remember having 3 year old versions arriving on the workbench with completely flat tubes. Many of these were flat during the guarantee period but customers just became used to the poor picture quality requesting a service call when something more noticeable became apparent.
Mullard did replace a number of these low emission tubes well outside the guarantee period but you had to speak to the guys at New Road 'nicely' !
This very short life was quite a surprise due to the longevity of the previous 20AX series that were fitted with an almost identical gun assembly. [These were usually destroyed in the Philips G11 smoothing cap saga rather than failing due to an unreasonably short service life.]
Something must have gone wrong in production, maybe an impurity or an unsuccessful change in manufacturing procedures. There is a lot of magic in CRT production.
Typical of Philips/Mullard the problem was recognized and soon rectified producing the later 30AX tubes that very rarely failed even after years of service. They probably produced the best quality picture ever with their 7.5kv focus potential, fat monitor crt type neck and pin sharp colour.
You may find a scrap receiver with a good tube. They can be replaced in about ten minutes, no convergence adjustment needed with just a tweak to the drives and grey scale. hope you get it sorted. The K30 is a cracking example of Philips technology. Regards, John.

Eidolon 20th Feb 2020 5:37 pm

Re: Philips 22CS1002/05t TV
 
Something very weird happened. I had a couple of days in which it warmed up very quickly, about 10 minutes, and in the couple of days since it hasn't warmed up properly at all. It's been om about 70 minutes now and it's still quite dark. 40 mins being the usual warm up time before. I've counteracted it a bit by turning up the brightness. I'm hoping that this problem is temporary like the fast-warm up was.

Is it fairly easy to spot how to un-boost it?

Not really sure how to name a thread looking for a replacement. 'Compatible Replacement tube for Philips K30 TV' maybe? And a list of the models mentioned here in the thread itself? :)

I recall the 'technician' turning a few things in the back, like screws I'd guess, to move the screen edge positions. I'm a little puzzled as to how the newer technician did such a bad job on the geometry, it's so off, hence why I'd like to do it myself this time. The distortion is very evident. But he did mod three of the channels into video channels, fix the jumping and flickering, and fix something else which was odd. When I had it on the dedicated VCR channel (8), it was noticeably only showing in one field. Didn't seem noticeable on videotapes, but on everything else it was very clear. especially if text was on screen. He sorted that out, not sure if it was technically a fault or if it was supposed to be like that as part of the design.

Heatercathodeshort 21st Feb 2020 10:41 am

Re: Philips 22CS1002/05t TV
 
It appears the cathodes in your CRT have completely failed. A bit like the dead parrot in the Monte Python sketch!

I think it has had it. Removing the 'boost' will probably reduce the emission to zero. The heater ballast choke on the CRT base connector has probably been shorted out to increase the CRT heater volts but this is a very short term dodge at the best of times. There may be one in each heater lead so you must check this very carefully as these shorted chokes need to be reinstated before installing a replacement CRT. Failing this the replacement will have a very short life.

A good CRT will warm up fully in 5-10 seconds. No need to list all the model numbers. You require a A56 540X 22" 30AX CRT.

I hope Polly Parrot still has a heartbeat. Regards, John.

Welsh Anorak 21st Feb 2020 11:43 am

Re: Philips 22CS1002/05t TV
 
You need to put "Wanted: A56-540X CRT". That'll do! Once you get one we can guide you through removing the boost modifications - it's not too hard.

linescan87 21st Feb 2020 3:11 pm

Re: Philips 22CS1002/05t TV
 
I wouldn't be too hard on the "technician". It sounds like he made the best of an otherwise impossible task.


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