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-   -   Restorer's dream part 2 the chassis. (https://www.vintage-radio.net/forum/showthread.php?t=67298)

Retired 24th Mar 2011 6:13 pm

Restorer's dream part 2 the chassis.
 
4 Attachment(s)
Hi,

Having now successfully completed the cabinet restoration of my 1957 Ekco T311 I would once again like to beg the indulgence of Paul and the moderators and be allowed to restore the chassis once again doing the restoration in real time. The extensive cabinet restoration can be seen here;

https://www.vintage-radio.net/forum/...ad.php?t=62371

Although by no means an expert I have restored many radio chassis and can tell the difference between a cap and a resistor but Iím a total rookie when it comes to TV work as this is my first one. Iíve already received many kind offers of help and advice and no doubt Iíll be very grateful for every one of these by the time this chassis sees first light as there is much to do; I previously described the chassis as in very poor condition which was a bad choice of words when I should have described the chassis as extremely filthy and dirty in fact like the cabinet the chassis looks like a wreck.

Please be gentle with me because Iím again sticking my neck out in public by attempting this restoration in real time and I have a great deal to learn but hopefully I will successfully restore the chassis whilst giving a blow by blow account of work in progress in order to help others in my situation by adding as much detail as possible.

Jeffrey (ppppenguin) has already kindly given me sound advice about not powering up without at least firstly sorting out the LOPT; (line output transformer) also Jeffrey very kindly sent me pictures of a LOPT he restored and I am grateful for such information as it gives me a good indication of what to expect.. The chassis is still sitting on the spare bedroom carpet but shortly I will disturb its slumbers and carry it into the workshop where I can inspect it closely. Before putting it into storage I used a compressor airline to blow most of the debris and dirt from the chassis so already it is looking somewhat better than it did and at least I can now see all the components.

New to me is the wire ended rectifier valve U25 as all the valves Iím familiar with have bases and pins whereas this valve is merely ďfloatingĒ on two wires the third being broken. Please bear with me whilst I get to grips with the various terms used in TV work such as ďRasterĒ which I believe is the picture on the screen.

Iím informed TV restoration can be easier than radio work because the raster gives a visual indication of faults and depending on what the raster looks like many faults are easily identifiable; please correct me at any time should I make a mistake as I sincerely want to learn how to restore this chassis and how to work on a TV chassis in general.

What do I need to know about safety? I believe there is some 16,000V present at the end of the CRT (Cathode ray tube) and also at the LOPT; Iíve already been informed that on this chassis such voltage would be most unpleasant to come into contact with but is unlikely to be lethal unlike a chassis with mains derived voltages in these locations. Are there any caps to watch out for that might be un-discharged as I work on the chassis? Is it better to assemble the speaker and CRT into the cabinet before commencing work or is it safe (with care) to have both loose on the bench to save bench space and avoiding damage to the newly restored cabinet. Iím used to having a bench full of live components so this doesnít unduly worry me.

I expect to do a complete re-cap given the age of the chassis and would appreciate any advice or information regarding problems in this area and also what kind of caps to use and where to purchase them from.

Jeffrey very generously supplied a new U25 valve with the set and my friend Harold has very kindly supplied me a number of other new valves whilst other members too have contacted me offering to help with valves. When I restore a radio chassis the first thing I do is to pull the valves one by one and test them on my AVO MK1 VCM; this not only ensures the valves are working but that they are in their correct sockets so I will make this my starting point assuming my VCM (valve tester) will test the valves; years ago I downloaded lots of valve data for my VCM so hopefully I can ease into this restoration rather than jump in and start making silly mistakes.

I have previously rewound a LOPT although at the time it was just another transformer to me and fortunately it was one of the normal windings that had gone open circuit not the wave wound one.

I have also bought a second hand Aurora but donít yet know how to use it and as we are on cable TV I assume Iíll need an aerial for the workshop and if so what aerial is recommended and where from?

At work I was always the one to ask the stupid questions whilst others all around me wanted to ask the same question but were scared to speak up; if I may be permitted I will ask the stupid questions in the hope that this thread becomes not only interesting but also instructive as well in supplying answers to very basic questions.

Unlike the cabinet restoration where I was very much out on my own I am certain this chassis will be an easier project in spite of my ignorance of the subject as there are so many TV experts on this forum whom I know are just waiting to bump start me into action. All suggestions and advice will be gratefully received by me so please sit back and enjoy the journey whilst I ramble on as usual.

Over the next few days Iíll get myself organized but to start with in the meantime Iím now gathering information.

To kick off with here are pictures of the chassis when I first collected the set; what a delight this restoration is going to be for me and I hope it turns out to be such a pain as the cabinet did as I hate a push over.

Kind regards, Col.

ppppenguin 24th Mar 2011 6:40 pm

Re: Restorers dream part 2 the chassis.
 
While there are a few things like EHT and round the LOP that can jump out and bite, this sort of set is largely no more electrically dangerous than a DAC90 or other radio with live chassis. All that you know about working with such radios is entirely valid for working with this TV so there's no need to worry on that account. All the caps will be totally discharged at the moment and will stay that way until you first connect power. For most of the caps the hazards are exactly the same as in a radio. The only extra thing to remember is that when you have EHT, the CRT can hold a charge for quite a long time after switching off. What's more, even if you discharge it, it can regain a charge. This is not directly dangerous, it's no more than a little sting, but if you jump and hit something then you might damage it or you.

The main extra hazard is a mechanical one. The CRT is a large amount of vacuum in a glass envelope. If you whack the faceplate or cone hard enough anyone standing in range will not be pleased about the trip to A&E. If you break the neck then all you will need is a another CRT. Please also try not to scratch the glass as this can give a localised stress point. Having told you how dangerous a CRT can be, in practice given just a touch of common sense there will be no problems at all. The glass is pretty tough and implosions are very rare.

The raster is simply the array of scanned lines on the screen, regardless of any picture information. I don't know the origin of the word.**

The Aurora will give you a test card simply by connecting it to a suitable power supply. This has been discussed elsewhere. Beware of the setting that lets it go into standby after a few minutes when no video input is connected. Several of us have been fooled by this. Read the manual for more info. Apart from the Aurora and power supply all you will need is a F to Belling & Lee adaptor or lead. If yours is anything but a very early Aurora it will also give audio tone in the absence of inputs. Once the set is giving test card and tone you can connect any video source to the Aurora. Such as a DVD player, VHS player, Freeview box, cable TV box etc.

To avoid damage to your lovely cabinet I make an unusual suggestion. That you jury rig a frame of wood, angle iron etc to hold the CRT, speaker and chassis securely. Effectively a skeleton cabinet that you can turn in any direction. I have never done this and I suggest it only in view of your lovely restoration.

I wouldn't bother to test the valves. Any problems will become evident as you run up the set.

Capacitor replacement is very much as in a radio except there are more of them. Any plastic dielectric types will do, 400V for most locations though there are a couple that I think need to be rather higher. Look at the markings since I don't think this is on the service data. As usual with a radio the cap on the mains should be removed altogether and replaced by an X rated type if you really want to retain a cap in that position.

**PS: I've just done a little online research and found that it's from a latin root about rakes and raking. http://www.thefreedictionary.com/raster

Steve_P 24th Mar 2011 7:18 pm

Re: Restorers dream part 2 the chassis.
 
Have you got a variac? This is a device to vary mains input. Wake the set up gently over a couple of hours, after you have remade the LOPT casing. Cut off the capacitor across the mains as well, otherwise it may go bang and scare the cat.

When you get first light on the screen then you're almost home, as most problems are with the PSU and Line Output/EHT stages.

As far as capacitor changes go, change one at a time and test after each change. This is for two reasons:

1: One mistake with one wire and you will be driven mad.
2: You can see which make the biggest difference, which can be fascinating.

A mirror for the screen is handy as you can look at the set from behind.

I'm here if needed.... you might find this site handy: www.oldtellys.co.uk Done by some complete idiot....


Cheers,

Steve P.

Heatercathodeshort 24th Mar 2011 7:37 pm

Re: Restorers dream part 2 the chassis.
 
I was going to suggest refitting the picture tube into the cabinet but Jeffrey's suggestion of using a simple 'jig' will preserve your cabinet.
For starters I would just use the air line to remove as much crud as possible and leave it at that until you get what we call 'first light' i.e. the first glimmer of illumination on the face of the CRT. This is the first indication of real life in the receiver and it is vitally important to obtain this at a very early stage. The power supply must be dealt with first followed by the line output stage. The rest is a doddle, honest.This is very important as many faults can be installed through over cleaning in the early stages. A certain amount of 'muck' will not effect the operation in any way and can be dealt with at a later time.
The LOPT looks terrible but I bet the windings will be OK. The single wire end [anode] of the EHT rectifier should be connected to a fine wire that exits from the circular winding called the overwind. If you are unlucky this may have broken off the main 'tyre' but with care the end can be found and a turn removed to allow reconnection. The case will need to be fabricated from Paxolin, sheet thermo plastic or similar. The windings and core are easily removed from the remains of the case. Make a note of all connections.
When you have done this task the general procedure is to give the chassis an overall examination. Clean all the controls and valve bases with a squirt of switch cleaner and snip the mains filter capacitor located behind the mains dropper on most models. If you do not have an isolating transformer you will need to ensure that the chassis is connected to mains neutral before connecting it to the mains. I would suggest a lamp limiter/variac when making early tests. I expect all the valves will be OK as they are run under ideal conditions in Ekco receivers. There are many simple checks to make before mains application and when the LOPT has been dealt with we can take it further. I think it will be a lot easier than you may suspect. Regards, John. P.S. Good luck with it!
[Sorry Steve! I was writing this as it appears you were yours.]

Danny 24th Mar 2011 11:45 pm

Re: Restorers dream part 2 the chassis.
 
Hi if the lopt is duff i should have a spare with the plastic casing intact but try to salvage yours first. the rest of the shassis will be fairly trouble free to get going if you do a recap on it. Danny

Heatercathodeshort 25th Mar 2011 9:24 am

Re: Restorers dream part 2 the chassis.
 
I have listed some of the stock faults that I encountered with the Ekco 300 series receivers that may be of use.

1 Mains fuse blown. PY32/33 heater O/C. [Models with radio only]
TV/Radio 'trombone' switch blown up. Rewire for TV only.
2 Mains fuse blown.
Mains filter capacitor usually mounted behind mains dropper tag board S/C. [May have popped open.]
3 Line output transformer case broken down and burnt. Usually across top to start with. Early
signs are discolouration and a sweet ' vinegar' smell when you poke your head inside the
cabinet. The windings, incredibly, usually survive the abuse.
Cases are easily fabricated from Paxolin or any good pastic/thermo plastic material. Take
great care with delicate wires particularly the output from the EHT overwind.
4 No EHT. Strained line whistle. Boost diode U191 overheating.
Line linearity coil has slipped down former and shorted to chassis. It is mounted on the back
of the line output box. Warm it up and push it back up placing a grommet under the former to
prevent a repeat performance.
5 Strained line whistle after EHT rectifier heats up. Sometimes rectifier glows blue and
anode 'bell' glows a dull red.
EHT smoothing capacitor .001uf heavy leak or S/C. This can be removed with no noticeable
effect in most models. Slight line tearing at very high brightness settings may be noticed.
The 'carbon rod' is a voltage dependant resistor to aid EHT stabilization.
Again the set will work very well without it with its absence hardly noticed.
6 Bright raster. No picture. Weak washed out picture but no grain. Contrast
control when advanced causes picture to go negative or white.Sound normal.
Vision detector diode mounted under clip on top of final vision I.F. transformer EXTERNALLY
O/C or leaky.
7 Strange AGC effects with odd operation of contrast control.
You forgot to change the .1uf waxie INSIDE the tuner unit. You will have to unclip the R.F.
tuning biscuits to gain access. Make a note where there go back...
8 No frame sync.
Q3/4 clipper diode O/C. It looks like a fat resistor and is band coded Orange/Yellow. Replace
with any diode such as !N4148 or IN4001 etc.
9 No operation of fine tuner.
Fine tuning slug snapped in half.
Tune oscillator biscuit through hole in side of cabinet for best position. The tuners are so
stable and will not drift. Best to remove old slug under cam and spring. [Examine mechanism]
to prevent it floating about.
10 Buzz on sound that can be removed when volume control is backed off.
[Not miss tuning]
O/C very small common electrolytic usually chassis mounted.
11 Frame cramp.
Same as above. 500uf section.
12 Purple glow in EHT rectifier [More U25 than U26] together with picture enlarging when
brightness advanced.
Faulty rectifier valve. [Very common]
13 Picture 'splutters' together with sound of arcing.
Boost diode has flaking cathode. [Good old Mazda] U191 in 300 series. U301 in 200 series.
14. Low sound.
Check all the screen decoupling capacitors .003uf in the I.F. amplifiers.
They again look like resistors and you will discover them to be O/C.
15 Vision instability. Difficult tuning. Heavy patterning.
Check the .003uf' capacitors but this time in the vision I.F. amplifiers.

You may be tempted to do the lot in one go, fine if your experienced at doing this type of work but
mistakes can very easily be made that take hours of back tracking to locate. Ekco receivers warm up
quickly so take your time, one component at a time. [It's fun to see the faults unfold]
All the waxies will have to be changed. I would suggest the CRT first anode decoupling, boost capacitor and the line coupling to be top of the list and the first to replace.

This about covers the non flywheel sync models and should be enough information to allow you to obtain
'First Light'.

Ekco receivers should have masses of extra height available and the timebases should lock absolutely solid
with no drift whatsoever. All the controls will be at their correct settings around mid way and will remain so for
many years. I will probably remember a few more odd faults as the day goes on. If I do I will post them!
Good luck with it. Regards, John.

dominicbeesley 25th Mar 2011 2:19 pm

Re: Restorers dream part 2 the chassis.
 
Hi Col,

I forgot to bring an Aurora manual with me when I dropped off the Aurora.

The manual is at http://www.tech-retro.com/Aurora_Des...downloads.html (I think yours is a 2.2 SCRF one - it says on the bottom). Like Jeffrey says all you need is a centre positive 9V power supply and an F connector - I'll dig you some out this afternoon I keep forgetting!

When you need some real pictures you can feed them in with a SCART to composite cable - I think I brought you my bodged together one or did I forget that too!

Dom

Retired 25th Mar 2011 8:50 pm

Re: Restorers dream part 2 the chassis.
 
3 Attachment(s)
Hi,

I was so full of enthusiasm for today and looking forward to getting everything set up ready to make a start on the chassis until Bronwyn told me Furball had suffered a wound to his head so that scuppered my best laid plans.

Furball was taken to the vets this morning and we have finally brought him home; he has been bitten but is now patched up and although we are £100 lighter in the pocket donít begrudge paying as we love him to bits and he is so adorable.

Thank you Jeffrey for all the information and suggestions; I liked the idea of making a stand to safely hold the CRT whilst I work on the chassis and have now made one as can be seen in the pictures; whilst I was designing the stand I thought why not include a speaker mount rather than have the speaker loose on the bench; the stand looks a simple affair but took a bit of thinking about; I used offcuts of timber and utilized some of the rubbish plywood I had to hand; I enjoyed myself for a couple of hours running my machines and the stand cost me nothing for materials; it is screwed together and through drilled to accept four 8mm dia nuts and bolts to securely locate the CRT; the speaker is secured with a pair of machine screws and nuts. Also Jeffrey Iíll heed your advice about not bothering to test the valves. Thank you for the raster link.

Thanks Steve for the link to your website which looks very interesting and Iíll have a more in depth look at it a bit later also I think your suggestion of using a mirror is very useful and Iíll try this out. Yes Steve I actually have two Variacs and I also have a 100W test lamp and an isolation transformer; Iíll take your advice when Iím ready to power up after sorting out the LOPT by using the Variac; I like the gentle approach rather than just switch on and wait for the smoke and bangs. Thanks for the offer of help.

The offer of the LOPT is very kind of you Danny and I hope I donít have to accept but it is good news to know one is readily available; Iíll know shortly if mine is working when I test it for continuity. It looks rough but Iím assured by other members these LOPTís are quite robust.

Youíve certainly given me a list to work through John and again I would like to also thank you for taking the time and trouble to compile it because by adding it to the thread it will be very useful to other novices as well as me; Iíll print off all the information and refer to it once I start the restoration. Iím very surprised to hear that a TV chassis isnít really so difficult to repair but of course I have yet to try it out for myself; I had got the idea into my head that I was in for some serious grief especially given the look of the chassis. I still hope to add plenty of notes as work progresses then it will make a good reference for other novices.

Thanks Dom; yes you kindly brought the scart cable and thank you for the link which Iíll have a look at. Iíll look forward to receiving the connectors but there is no hurry as I still have plenty to do. Iíll keep in touch by email anyway as normal.

Iíve not even yet started work on the chassis but already am getting a feel for what is involved just by reading all the information kindly given to me so far; for someone used to TV chassis restoration this information will probably be taken for granted but for me it is all brand new and I canít thank you all enough for supplying it.
What Iíve learned so far is to relax and enjoy this project; make a stand to secure the CRT and also use a mirror to view the screen. Donít bother to check the valves. Completely restore the LOPT and make a new insulated housing for it. Ensure the chassis is electrically safe and when I do get round to applying power do so using a Variac bringing up the voltage slowly possibly over a couple of hours but keep it under observation. Iíll also do the usual checks of the mains lead plug and fuse and I noticed the on/off switch had a nice firm click when I tried it earlier today. I wonít over clean but I have already used the airline to gently remove most of the debris and accumulated dirt. Iíll wait until power up then only change one component at a time then applying power after each to watch progress; Iím not scared but I will be careful around the high voltage areas and Iíll be extra careful of the very thin connecting wire at the LOPT.

Iíve been retired now for ten years and still canít seem to get a day where I have total peace and can work uninterrupted either in the workshop or garage; every day something prevents this from dire weather; Jehovah Witnesses whom Iíve been polite to; insulted and been rude to them and told them Iím not interested so two more new ones turn up the week after and a continual steam of unwanted visitors who think because we have a large detached bungalow we owe them something for nothing. If I have a rare warm day allowing me to work in the garage with the doors wide open then Iím on stage to be interrupted by every passer by; tree surgeons drive me mad. Iím not anti-social and like a natter but not with double glazing salesmen or any of the other cowboys wanting to attack our property. I couldnít even speak to my friend Mike Phelan when he rang this afternoon as we were just setting off to collect Furball. I find it hard to settle. Yes Iím moaning but I do get fed up with not being allowed peace to concentrate on the job in hand and this can be dangerous if Iím using one of my machines in the garage.

In order to concentrate on this chassis Iíll do the work in the workshop which is hidden out of the way at the rear of the bungalow and Iíll work in comfort with the heating on. I think Iíve suffered enough during the cabinet rebuild.

We are pleased to have Furball back home and Iíve included a picture of him for the cat lovers. Furball is just gorgeous.

My plan for tomorrow is to set everything up in the workshop so hopefully I will be putting all the suggestions and information into practice very shortly.

Kind regards, Col.

David G4EBT 26th Mar 2011 10:09 am

Re: Restorers dream part 2 the chassis.
 
Sorry to hear of Furball's mishap Colin - he looks very displeased, indignant and reproachful, and as always, very magisterial, as befits his station in life as the head of the household and master of all he surveys! (As to intrusive callers, having seen the pics of the tree that you felled, the last thing you're in need of is a tree surgeon! You'll have another distractive intrusion into your lives tomorrow - your census form to fill in).

The stand looks excellent - I hadn't appreciated just how vulnerable the neck of the tube is, sticking out as far as it does. It will be interesting to see how the chassis comes along stage by stage. I think that generally, there's much more room to get at things on a TV chassis than a radio, so hopefully, when you get the layer of fluff and accumulated grime removed and can actually see things better, it might not look such a basket case. The same couldn't be said of the cabinet in its original state - the closer you got to it, the grimmer and more hopeless it looked. But as they say - 'the rest is history' - mission accomplished in that deparment!

Looking forward to hooking up with you at Golborne.

David

Retired 31st Mar 2011 2:38 pm

Re: Restorers dream part 2 the chassis.
 
5 Attachment(s)
Hi,

Many thanks David and yes Furball is now fully restored into his position as master of the household none the worse for his wound which has now healed.

Since moving here Iíve felled many large trees but there are plenty left including two oaks and a blue spruce; the high wind up the valley side is trying to fell these for me today.

I agree the tube neck does look very vulnerable; I was surprised how long it was but then this is my first TV restoration so everything is new and strange to me. I believe the time taken to make the tube and speaker stand will be well worth it as both are now safely supported and can be moved around without difficulty.

The cabinet was indeed very rough and I think by restoring this first the hardest part of the job is now well behind me although the French polish to the cabinet top has slightly settled into the grain but doesnít warrant extra work and Iím happy with it. The chassis however looked incredibly dirty and even after blowing it off with the compressor air line it still remains very scruffy; every time I handle anything on the chassis my hands quickly become coated in grime but taking the advice offered Iíll endeavour to see first light before attempting a proper clean up. One blessing though in getting a set in this condition is that it hasnít been messed around with for many years.

Iím fed up moaning about the weather so this morning I put the heating on in the fridge (workshop) allowing it to warm up for over an hour before venturing in; I havenít done any serious work in there for well over a year so first job was to tidy up and whilst tidying up I switched on four radios to check if they still worked but all was well.

With the benches cleared and everything tidy I was soon feeling comfortable and was surprised at how quickly it had warmed up. I carried the chassis in and placed it onto the bench then collected my notebook and camera so at last I was ready to make a start. The LOPT looked terrible as though it had been on fire and I held out little hope that it would be of future use; a number of the wires were broken and I presume it once had an insulated housing around it; well it doesnít now and before blowing off with the air line the metal surround was full of debris. I made a note in the pad of the connections and also marked each connection using masking tape before snipping the leads.

With the LOPT now on the bench I could clearly see the damage. I noticed a single turn of winding wire around the outer circumference of the overwind and this easily pulled free its connection having burnt completely through; I thought it would be a waste of time but scraped the wire end clean and used a hook up to connect the multimeter to it then I prodded around and was totally amazed to find continuity between the overwind and the top cap of U191 I think this is the valve number but it was very dirty. Also continuity was shown to a loose lead that disappeared below chassis to a multi soldered connector; I marked this lead and it could possibly connect to U25 as U25 had a lead connected to each end and also a broken third connection? This was only a preliminary check and Iím trying to add comprehensive notes for other novices like me trying to restore their first TV. Finding continuity through the overwind really cheered me up; Iíll have to do some circuit tracing in order to re-connect everything correctly but itís a good start and now I can design and make a new insulated enclosure for the LOPT; not today though because I dare not open the garage doors due to the high wind and I would be worried about getting the car damaged due to airborne debris flying around.

I took a number of pictures then knocked off for dinner; I spent a nice couple of hours in the workshop this morning and now need to get more geared up in order to fully concentrate on the chassis. Jeffrey very kindly sent me pictures of his home made LOPT enclosure and Iíll study these; Iíve been searching for a better T311 circuit diagram but so far have only a diagram in a TV servicing book that has many notes written upon it; I would like a clean diagram then I could take it and have it enlarged at a local printer. If anyone has such a diagram I would be very obliged to receive a copy and am willing to pay. I have Paulís DVD but it is not shown on this.

Iím not in a hurry and will sit back to enjoy this chassis restoration after all I know if I try to rush the job Iíll only be heading for disaster and it is the work I do that is more interesting to me than to actually be looking at a finished restoration. This is going to be fun and as with the cabinet Iím well up for the challenge.

Kind regards, Col.

Mike Phelan 31st Mar 2011 4:56 pm

Re: Restorers dream part 2 the chassis.
 
Col

I do have a good circuit diagram and things for the T311 in Volume VI of Newnes here.

PM or eMail me if you want to pop over and borrow it.

The valve is a U191, efficiency diode. As for the U25 connections, the anode is the one by itself and connect to the overwind, the other two are for the heater with one side connected to the cathode. One end of this goes to the final anode lead to the CRT.

Even though the overwind is not OC, any burning may be suspect and fail with high voltage on it.

Retired 31st Mar 2011 5:15 pm

Re: Restorers dream part 2 the chassis.
 
Hi,

Many thanks Mike for the offer of loaning me the book and also for the information it is much appreciated.

I hope to pop over before Easter anyway and will keep in touch as usual by email.

Making the new LOPT enclosure will keep me occupied for a little while once I make a start on it; One thing I didn't do was to measure the other LOPT windings.

I'll know a lot more about a TV chassis before this one is fully working again.

Kind regards, Col.

Heatercathodeshort 31st Mar 2011 7:22 pm

Re: Restorers dream part 2 the chassis.
 
A word of caution here Colin. I don't want to see you go to all the trouble to make a new casing and then find the transformer burnt and useless. That does look very bad with the EHT winding actually burnt. It does not look good to me and it might be worth obtaining a replacement that is in reasonable condition. I have never seen one so badly burnt and would have been the reason the set was put out of commission. Usually they have just tracked over and stank the room out. These can always be salvaged. It never fails to amaze me how customers continue to watch a receiver that is spluttering and smoking and refuse to switch off until the actual appearance of flames! Even if you find a transformer with a burnt case these are generally repairable but the windings are very rarely burnt as yours. I have checked my stock but no luck. Maybe another Forum member may be able to help. Regards, John.

Retired 31st Mar 2011 8:07 pm

Re: Restorers dream part 2 the chassis.
 
Hi,

Many thanks John and I agree the LOPT looks and is terrible; thankfully I have experts like you and Mike to steer me through this restoration. What a joy it is to find the chassis in the same condition as the cabinet and I wonder if from this humble start the chassis restoration will end up as another very long thread and I thought I was over the worst?

Help is close to hand though and I've just sent Danny a PM (post #5) enquiring about the spare LOPT he kindly offered.

I'm pleased to see most of the caps are dead easy to access with plenty of space around them; as already suggested I'll wait until power up then change these caps one by one; with luck being aged only 63 I should live to see this restoration completed.

This is going to be entertaining and great fun together with another steep learning curve. At the moment I'm only nibbling around the edges but will ease my way in as this is turning into a full blown restoration.

Kind regards, Col.

valveman49 31st Mar 2011 8:57 pm

Re: Restorers dream part 2 the chassis.
 
1 Attachment(s)
Hello Col
I realise that you have made arrangements for a copy of the drawing for your set, but as I scanned my copy and cleaned it up earlier today, I thought it may, help other forum members follow the restoration if I posted a PDF copy of the information.
If this is not allowed could I ask one of the moderators to remove it for me?
Regards Stan.

Steve_P 31st Mar 2011 9:07 pm

Re: Restorers dream part 2 the chassis.
 
You could try giving it the Panrock Bush TV22 treatment?

It's included in this very enjoyable read. http://www.radiocraft.co.uk/902.htm

Cheers,

Steve P.

Danny 31st Mar 2011 9:35 pm

Re: Restorers dream part 2 the chassis.
 
Hi i actually have a hole scrap set if that would be of any use to you but it is a 14" set i think the shassis and lopt are the same. the only snag is getting it to you. if not i can find a lopt but i wont know what screen size its from. let me know what you want to do.

KeithsTV 31st Mar 2011 11:21 pm

Re: Restorers dream part 2 the chassis.
 
2 Attachment(s)
Colin

Once you.ve got it working you'll need the instruction book. My parents rented the 14" version for a short while but kept the instruction book when the set was returned. (I don't think they thought much of the idea of paying extra for the radio so got a radioless version).

I've attached copies of both instruction books, the 326 has a picture of the set but it's not a patch on your cabinet.

Keith

Heatercathodeshort 1st Apr 2011 2:32 am

Re: Restorers dream part 2 the chassis.
 
The LOPT from the 14" chassis should be fine in the 17". I used to have a cross reference chart but that was half a century ago. It will definitely work. J.

Retired 1st Apr 2011 10:59 am

Re: Restorers dream part 2 the chassis.
 
Hi,

Thank you Stan for taking so much trouble on my behalf; perfect job and Iím sure posting the circuit diagrams on the forum will also help others. I did check Paulís DVD first and couldnít find this set listed so I donít think it will be a problem adding them.

Wow!! What a beautiful restoration of the Bush 22 Steve; its amazing and I can only aspire to such work. Thanks for adding the link.

Iíve already sent a PM to you Danny and I canít thank you enough for your kind offer of the scrap set; Iíll try to arrange collection through the forum courier service. Itís possible other bits from your set will also be of use. I wouldnít be surprised to find your scrap set to be in better condition than mine when I first obtained it.

Iím delighted to receive the manuals Keith and will print them out also thanks for your most welcome email; Iíll reply shortly as Iíve just got my email working again after receiving ďTimed outĒ error messages.

Itís very reassuring John to hear the LOPT from Dannyís set is a direct replacement and once it arrives I can make a new enclosure for it; thank you for the information.

Itís wonderful to have so much support and expert advice because otherwise I would have struggled to restore this chassis; I still have a big job on my hands as the chassis is rough but Iím confident with all the generous help and information I should succeed.

I think Iím an hopeless case being addicted already to tinkering around with TV sets because although I donít know what condition the scrap set is in that Danny is kindly letting me have it ran through my mind to experiment at repairing it once my T311 is fully sorted after all I will still have the original LOPT from my set and it would be fun to see if it will actually work; if it goes up in smoke then nothing lost.

Kind regards, Col.


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