Restorer's dream part 2 the chassis.

[brianc]

Originally Posted by Retired

Too many jobs and not enough time.Kind regards, Col.

That's retirement for you Col. A super thread and what workmanship - and tenacity!

[Retired]

Hi,

Many thanks for the kind comments and offer of a connector Peter; I've now sorted the mains supply as below.

I'm sure if I had a warehouse David I would want a bigger one in no time.

Thanks Brian and I'm still battling on; I thought I'd sorted everything out but have spent another half day on the chassis today.

I had wired the mains directly to the switch by-passing the original male connectors to the rear of the chassis and I intended to remove the connectors. I thought about this and decided to have a go and tidy the mains supply up a bit so this morning made an early start.

I have a number of modern 3 pin sockets and connectors so decided to fit one and first job was to remove the two pins by drilling to release them after snipping the connections. A card template was then carefully made and used to mark the position of the new socket. The four corners were drilled using a pilot bit then opening out with a larger bit.

The panel was then released from the chassis and the bulk of the waste cut away using a fretsaw fitted with a fine piercing saw blade; this was extremely fiddly work as the panel remained connected. Next job was to spend time and use needle files to bring the opening to the marked lines then insert the socket and drill for it's mounting screws.

With the new socket securely installed I wasn't happy as the original fuse holders and fuses could pose a real danger being as exposed as they were so the job just got bigger.

The original fuse holders were drilled and removed then holes carefully marked; drilled and opened out with needle files; a tedious job which took quite a bit of time but to try to drill with a large bit would have possibly destroyed the Paxolin panel on breakthrough.

The new fuse holders were then installed and everything connected as per the circuit diagram. All went well until I was connecting the 500mA fuse; one end traced to HT and was correct but the other end had been connected to the on/off switch which was most strange although the set worked; I followed the circuit and connected it in it's rightful position. I'm aware this is not original but then neither is the cabinet but I feel the mains connection is now safe.

The earth pin is not connected.

I've just come out of the workshop and at last I'm pleased as everything now appears to be correct; sound and vision are working and the mains supply looks much tidier.

I'm now happy to proceed with assembly so with luck I should have the set fully assembled and in working order in the next few days. My fingers are well and truly crossed.

Kind regards, Col.

[ms660]

A vast improvement on the original, nice and safe now Col.

Lawrence.

[Retired]

Hi,

Thanks Lawrence; yes it is much safer now.I was worried about someone coming into contact with the fuses whilst pushing the mains lead home.

Normally I have lots of patience but I just knew when I got out of bed this morning it would be severely tested. I was proved right.

Lack of bench space really wound up the big key in my back as I struggled to assemble everything. The cabinet was balancing over the bench edge and I draped a multi-folded bed sheet over it as it was in great danger of getting damaged. I didn't want to separate the CRT from the chassis as everything was set up and working.

The loudspeaker was first job and eventually after searching for some suitable wood screws it was installed followed by the CRT. The chassis went in after a bit of a struggle and it still requires some alignment as the front controls are not equally spaced from the baffle board and the side control housing protrudes a bit more than it should but at last it was all finally put back together and what a joy it was to see it in full working order.

I then carried the set into our front room to try to take some decent pictures but it's like a black hole outside today and when the sun came out it caused further problems so in the end I closed the roller blinds and took numerous shots with and without flash enabled. It was a wonderful sight watching the test card being displayed and at last after months of dedicated work I thought I could declare it a success and a "restorers dream come true".

The test card displays very well but I had problems taking a decent picture.

A number of my radios were moved around in the front bedroom and it was found a decent home ready to play for when friends visited us. My joy was short lived though because when I switched on I heard a "crack" and after a short while the screen remained dead.

I lifted the set onto the bedroom carpet and tried to see what was wrong but it was too dark and gloomy even with the light on so I collected the inspection lamp from the garage. With the power switched on I waited and after a while noticed a bright glow which turned out to be the two HT 35R resistors overheating.

After so many months of hard work and problem solving the set now thanks me by having what appears to be a direct short on HT; I had a good look around to see if any bare wires or components showed signs of being disturbed but all appeared to be OK; at this point I walked away in disgust.

I've struggled enough for one day but it won't beat me even if I have to drag it back into the workshop. What it can't take away from me is the vast amount of pleasure I've had and the masses of experience gained whilst working on it. Compared to the work thus carried out I don't think an HT short is going to be too taxing to sort out and hopefully I can find it by using the DMM with the chassis still on the carpet.

I have however solved my printer problem. Yesterday after much web surfing looking at printer reviews I ordered a new HP LaserJet Professional P1102W mono printer. I was amazed because it arrived today at dinner time and boy what a difference over the Samsung it replaces. Black is now black unlike the Samsung's dark grey and it is rapid. By shopping around on the web I got a good deal at £70 delivered; the same printer is listed at £99.99 at our local computer chain store.

It was a disappointment to have the TV fail so quickly after success and I feel a bit fed up with it behaving like this but these things happen and it's not the end of the world. I have achieved my dream insomuch that I've taken a wreck of a TV and fully restored it and below are pictures of it in all its glory. I have a deep sense of satisfaction and having worked on this my first TV I feel I've moved on from being a total novice. I will add the details of the fault in due course.

The cabinetwork was without doubt the hardest part of this restoration as I was totally on my own but although I had serious doubts about ever seeing this set working I would like to offer my most sincere thanks to all concerned who have helped me whilst I worked on the chassis with endless advice and information together with free components and also to thank each and every member for following this saga. It has turned out well in the end but it could also just as easily been a total failure. Thank you everyone.

Kind regards, Col.

[Steve_P]

Old tellies are like that Colin. Don't worry about it, the short is due to something touching where it shouldn't, so get new resistors and try again with them. It could be the valve.

But, this is a superb looking set now and well done for all your hard work. I trust you'll bring it to Golborne?

Cheers,

Steve P.

[Tazman1966]

What can I say but superb. A real credit to you Col and I'm sure you'll have the fault licked soon.

[Sideband]

Best thing is to give it a rest for a day or so and then get back to it with a positive attitude. It may well be the rectifier valve that has died...these things happen. You've done an absolutely brilliant job on it. It's just throwing it's weight around and you have to show it who's boss!

SB

[Heatercathodeshort]

It could be the rectifier Colin but the later PY33 very rarely fails. Much more likely to be a shorted wire or maybe one dropped off and shorted to chassis. Remove the rectifier, replace the two resistors and switch on taking care. If they overheat you have a trapped wire from the dropper area. If they overheat as soon as the rectifier is replaced the valve could be faulty. [ I doubt it] Finally measure the H.T, line for a short, again very unlikely other than a shorted wire to chassis. The only thing you have done is disturb the chassis fitting it back in the cabinet so I reckon it's a made made fault. It will be a very simple one. John.

[Mike Phelan]

I'm with John on that, Col. It will just be a mechanical fault when you've been moving it around.

[Retired]

Hi,

Many thanks Steve and yes I would like to take it to Golborne but when I took the restored cabinet to the last Golborne meeting I had a lot of trouble getting it into the car without damaging it; now that it is fully assembled I've no chance of loading it into the car. When you kindly collected it for me and I picked it up it didn't matter because I could hardly cause it more damage considering the condition it was in. Our car is a Toyota Aygo which is not really suitable for transporting bulky items around. I do however intend to bring along my fully restored AVO wave winder together with the box of new gears I made to put on display.

Thanks for the encouragement Tas; if it doesn't behave I always have a big hammer as plan B.

I'm sure you are right SB; it is trying to wind me up and yesterday doing a good job of it but today I'm fully charged up and more relaxed; I just hope I can find it as it is so dark and gloomy. Thank you for your warm comments they are much appreciated.

I'm confident that you are right John; the set worked fine on the bench and also after assembly as I took the pictures of it working fully assembled in our front room; it was only after moving it into the bedroom that it decided to sulk; it might not like the company as it is surrounded by radios. I'll take your excellent advice and pull the PY33 and install a pair of new resistors then work from there.

When I assembled it I threaded the loudspeaker leads across the front and down the side of the chassis; I could only do this by feel and it is possible that by doing so something has been brought into contact causing a short. I'm rather surprised that both big resistors are glowing though. At the moment HT is protected by a 2A fuse and I need to change this to the correct 500mA once I obtain a new fuse.

I'm still as keen as ever to get this set fully working but with it now sitting on the bedroom floor and the weather making everything so gloomy and miserable it is hardly the best environment to be working on a TV chassis; I'm six feet tall and its a long way down to the floor to work on my hands and knees; to make matters worse I only have one knee cap making kneeling a bit uncomfortable. One thing is for sure; it won't beat me; I've not spent months on this set just to give up now even if I have to drag it back onto the bench so it can give in peacefully or end up with a fight on its hands.

Kind regards, Col.

[brianc]

Originally Posted by Retired

Our car is a Toyota Aygo which is not really suitable for transporting bulky items around.

It's no good Col. You'll either have to give up TVs (and radiograms) and stick to radios or get yourself a more "suitable" vehicle - perhaps a Ford Transit

[dominicbeesley]

Hi Col,

Don't despair it always goes like this, the lurking problem always waits until you've put everything back in the cabinet before coming back to get you! It looks pretty excellent back in its lovely cases though!

For taking pictures of tellys - don't use the flash as they always just look poor and the shutter speed is usually so fast on automatic cameras that you get a dark band on the screen. I find with modern cameras and phone cameras a not too brightly lit room (i.e. just a few 60w bulbs) and turn the contrast down on the set usually gives a good picture. However, if your camera will do manual focus, aperture, iso and exposure it is well worth taking your time to familiarise yourself with them as taking pictures of TVs often confuses the automagical features of many cameras.

Dom

[Retired]

Hi,

A Ford Transit is a good idea Brian; I'd like a Transit and also keep our little Aygo which we love.

Thanks Dom; yes it is always most frustrating for a problem to arise right at the very end of a difficult and long project. Thanks also for the camera information. Next time you visit you will be able to see the set first hand.

My determination kicked in with a vengeance this morning; this set has thrown many problems at me but this was it's biggest mistake as I was going to get it working whether it liked it or not.

I carried a selection of kit into the bedroom and installed a new pair of 36R resistors; with PY33 removed the chassis behaved but once the valve was re-fitted the resistors started to heat up so I declared all out war on it. I was fed up of working on my hands and knees so pushed the chassis loosely back into the cabinet and carried the lot into the workshop.

Once again I removed "the works" and set everything up on the bench. I then spent an hour checking everything but couldn't find anything amiss; all the leads were still connected and I couldn't see anything touching the chassis that shouldn't so it was baffling. I then switched on again with the intention of taking voltage readings but noticed the power supply feeding the Aurora had a flickering needle? it appeared to be pulsing with the flash of the LED on the Aurora?

At last I had found the fault; the power supply not the Aurora or set was taking the Mickey; as I had been moving things around yesterday I must have knocked the switch changing it from volts to amps. Being thick it took a bit of sussing out at first as all during this chassis project the power supply has behaved and given my luck it would be the thing causing the problem it being out of sight as I stripped the set down just for the fun of it!! It must have been having a right laugh at my ineptitude.

Switching back to volts everything came back to life; I checked for audio and it was fine so I then assembled everything once again and the set is now fully working in our front bedroom. A bit of adjustment is needed to align the picture once again and the next time the chassis comes out I'll modify the mountings slightly to allow better alignment of the knobs and the side control panel cover but on the whole I'm now over the moon and still think its a miracle this set is working at all. Here is a picture of it in the front bedroom.

I think you will be the first to see it working Mike when you visit on Friday; champagne not required but I'll get the coffee on ready.

Kind regards, Col.

[ppppenguin]

Congratulations on getting it working again. I can't quite follow what the actual fault was. The Aurora was unhappy because its PSU was unhappy but don't see how that could have caused the overheating problem in the TV.

[Retired]

Hi,

Thanks Jeffrey. I haven't a clue why the set behaved the way it did with the power supply switched to "amps". It certainly wasn't happy and I did nothing else by way of touching the chassis; switching the power supply to volts cured the fault.

On volts I had the supply exactly on 9V but noticed with it on amps it was reading something like "4". Would it be possible that power was being fed into the aerial pick-up whilst on amps?

I must have knocked the switch on the power supply yesterday and this is what was causing the problem. PY33 and both resistors became very hot in fact the resistors were glowing before I noticed them.

The set is happy now and one thing I will do is to obtain a fixed 9V power supply to prevent future problems.

Kind regards, Col.

[HamishBoxer]

Got me confused as well Colin, normally PY32 feed resistors glowing are due to HT short or valve itself. However main thing is you are up and running.

David

[ppppenguin]

Let's speculate a little. Due to PSU troubles the Aurora misbehaves and generates what seems like line syncs that are far too slow. Line timebase in T311 attempts to lock to this. Current in line timebase is far too high as a result. Stuff overheats.

If this speculation is correct I would expect the line scan to have been making horrible shrieking noises.

[HamishBoxer]

Wouldn't have expected PY32 to overheat like ,more the PY in the line would or U191 etc.

David

[Retired]

Hi,

Thanks David and Jeffrey. This set is playing games with me. Out of curiosity it was easy to check as I've just switched on; firstly with the power supply at 9V then switched over to amps and the set is now behaving reading just over 0.2A.

How weird is this. The test card did not display whilst the set was on the bench with amps selected but as soon as I switched to volts it appeared instantly.

I know very little of electronics but life would be much easier without these gremlins winding me up.

I was awake last night wondering what the fault could be and was quite concerned as I could have toasted bread on the resistors yesterday. I'm not surprised it wanted to have one last dig at me considering the many problems it threw up during the restoration. Perhaps it has now finally shaken hands with me and become friends.

The bench looks much bigger in the workshop now.

Kind regards, Col.

[Mike Phelan]

Jeffrey
Not convinced on that one; I think if the line osc is free-running at more or less the right speed and can be synced to 10125, anything the Aurora did such as very slow syncs would only pull the T311 off far enough to still produce a raster.

Even if so, as HB says, the 30P4 and U191 would start to glow first?