Restorer's dream part 2 the chassis.
 

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 I’m a total rookie when it comes to TV work as this is my first one. I’ve already received many kind offers of help and advice and no doubt I’ll 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 I’m 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 I’m familiar with have bases and pins whereas this valve is merely “floating” 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 “Raster” which I believe is the picture on the screen.

I’m 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; I’ve 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. I’m used to having a bench full of live components so this doesn’t 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 don’t yet know how to use it and as we are on cable TV I assume I’ll 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 I’ll get myself organized but to start with in the meantime I’m 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.

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

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.

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.]

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

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.

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

Re: Restorers dream part 2 the chassis.
 

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 don’t 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 I’ll 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 I’ll have a more in depth look at it a bit later also I think your suggestion of using a mirror is very useful and I’ll try this out. Yes Steve I actually have two Variacs and I also have a 100W test lamp and an isolation transformer; I’ll take your advice when I’m 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 don’t have to accept but it is good news to know one is readily available; I’ll know shortly if mine is working when I test it for continuity. It looks rough but I’m assured by other members these LOPT’s are quite robust.

You’ve 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; I’ll print off all the information and refer to it once I start the restoration. I’m very surprised to hear that a TV chassis isn’t 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 I’ll have a look at. I’ll look forward to receiving the connectors but there is no hurry as I still have plenty to do. I’ll keep in touch by email anyway as normal.

I’ve 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 can’t thank you all enough for supplying it.
What I’ve 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. Don’t 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. I’ll 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 won’t over clean but I have already used the airline to gently remove most of the debris and accumulated dirt. I’ll wait until power up then only change one component at a time then applying power after each to watch progress; I’m not scared but I will be careful around the high voltage areas and I’ll be extra careful of the very thin connecting wire at the LOPT.

I’ve been retired now for ten years and still can’t 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 I’ve been polite to; insulted and been rude to them and told them I’m 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 I’m on stage to be interrupted by every passer by; tree surgeons drive me mad. I’m 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 couldn’t 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 I’m 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 I’m using one of my machines in the garage.

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

We are pleased to have Furball back home and I’ve 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.

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

Re: Restorers dream part 2 the chassis.
 

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 I’ve 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 doesn’t warrant extra work and I’m 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 I’ll endeavour to see first light before attempting a proper clean up. One blessing though in getting a set in this condition is that it hasn’t been messed around with for many years.

I’m 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 haven’t 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 doesn’t 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 I’m 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; I’ll have to do some circuit tracing in order to re-connect everything correctly but it’s 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 I’ll study these; I’ve 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 Paul’s DVD but it is not shown on this.

I’m not in a hurry and will sit back to enjoy this chassis restoration after all I know if I try to rush the job I’ll 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 I’m well up for the challenge.

Kind regards, Col.

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.

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.

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.

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.

Re: Restorers dream part 2 the chassis.
 

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.

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.

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.

Re: Restorers dream part 2 the chassis.
 

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

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.

Re: Restorers dream part 2 the chassis.
 

Hi,

Thank you Stan for taking so much trouble on my behalf; perfect job and I’m sure posting the circuit diagrams on the forum will also help others. I did check Paul’s DVD first and couldn’t find this set listed so I don’t 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.

I’ve already sent a PM to you Danny and I can’t thank you enough for your kind offer of the scrap set; I’ll try to arrange collection through the forum courier service. It’s possible other bits from your set will also be of use. I wouldn’t be surprised to find your scrap set to be in better condition than mine when I first obtained it.

I’m delighted to receive the manuals Keith and will print them out also thanks for your most welcome email; I’ll reply shortly as I’ve just got my email working again after receiving “Timed out” error messages.

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

It’s 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 I’m confident with all the generous help and information I should succeed.

I think I’m an hopeless case being addicted already to tinkering around with TV sets because although I don’t 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.

Re: Restorers dream part 2 the chassis.
 

Hi Col,

I look forward to re-joining you on your Chassis restoration after having been enthralled by your epic cabinet restoration,
regarding the cap replacement it maybe a good idea to replace the coupling capacitors to the audio output valve, the lineoutput valve and the frame output valve before powering up for the first time. They all come under the description of 'That Capacitor'!
This may well save the valves from overload if (and it is likely) that the coupling caps are leaky

Regards

Andy

Re: Restorers dream part 2 the chassis.
 

Hi,

Thanks for this information Andy; it makes a lot of sense; on this chassis most of the caps look very easy to replace and I would have only switched on for short periods anyway until I felt confident nothing was going to expire; I'll also bring it up slowly as Steve suggests with the Variac.

I'm pleased you enjoyed the cabinet restoration and every time I see the cabinet it gives me such a thrill; I hope this chassis restoration also turns into an epic but with all the expert advice available I don't think it will take too long before I see "first light".

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Hi Col,

All the best.
I cut my teeth on valve equipment!
Started out at the age of 13/14 with a faulty Pye VT4, and had 'TV Servicing' book by Gordon J King on extended loan from the local library.
At the time I knew very little about TVs but that first TV taught me an awful lot.
I'm looking forward to getting a 405 line tv that needs lots of TLC when I have built my workshop.
You are in good hands here on the forum(s)

Regards

Andy

Re: Restorers dream part 2 the chassis.
 

Hi all i must confess the scrap set isnt realy that bad but it has a low tube not usles but low i swaped the tube as i wanted a realy good one to tranceplant into the emi set i restored some time back the rest should be ok the lopt casing from my memory was also ok you may actually get a picture on it with a few cap changes the cabinet is poorly but with your skills may be salvagable. the main thing is to get some life into your creation. but you never know by the time you get onto your second set another spare lopt may turn up. hope you get someone on forum courier service to collect it. but i work week days so it would have to be evenings or weekends. Danny

Re: Restorers dream part 2 the chassis.
 

Hi,

Thanks for the good wishes Andy and your interesting notes. I came into radio restoration aged 54 as I wanted something to do during our long winters. I too am self taught and still have a great deal to learn but this to me is the fun in this hobby. Good luck with your workshop and don't forget to put some decent heating and lighting in as you will need both even more than me living further north.

I might end up with both a 14" and a 17" Ekco at this rate Danny if I can restore your scrap 14" set in due course. I'll be delighted to get my hands on it then I can make progress on my own set; until I get the LOPT sorted out I'm not touching anything else on my set as I could very easily lose the plot. Many thanks for your kindness.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Hi,

Unfortunately no one has yet been able to help with transporting the set from Danny in Norfolk to Huddersfield. If it is OK with Danny I would still like to receive his set although I have excellent news.

I couldn't believe my luck at the recent Golborne meeting; Mike from Cramlington was extremely generous in offering me a suitable LOPT in good working order and when I asked how much it would cost Mike would not accept any payment for it not even for postage and this was not cheap. I can't thank Mike enough for this as he is true to his word and I now have the LOPT shown in the pictures; this is amazing because this LOPT still retains a perfect plastic enclosure whereas my plastic enclosure had crumbled to dust this being all that remained of it.

These plastic enclosures have a habit of disintegrating and I fully expected having to make a new enclosure from Tufnol and Jeffrey had already kindly sent me pictures of the one he constructed so this now saves me a job.

I also have excellent circuit diagrams kindly supplied by Keith and Keith helped out further by identifying the valves on the diagram; I've just had a quick look and found where the LOPT is shown on the diagram which is a starting point because I'll need leading by the hand throughout this chassis work as it is my first TV chassis.

I'll print off all the information already kindly supplied in this thread which will be a great help to me and I'd like to thank everyone concerned for supplying it.

I wanted to start on the chassis today but I had a very bad night last night getting up at 7 o'clock this morning because I was in too much pain to remain in bed. My upper right arm was really giving me some grief and I think I might have strained or pulled a muscle whilst working around the bungalow; what a relief it is now the pain has subsided at last; it wasn't at all pleasant whilst it lasted.

Bron lopped six inches from my hair a couple of days ago so if I now come into contact with mega-volts on the chassis I won't resemble a mad professor as much.

I need to settle into my workshop next week which will be strange as I've not done any work in there for many months due to the bad weather.

I've added the pictures of the LOPT as received in the hope that they will help others.

I'd like to thank everyone for your help so far and I feel confident with your continued help we can pull a miracle off between us. Do I change the U25 whilst the LOPT is readily accessible sitting on the bench because Jeffrey very kindly gave me a new U25?

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

So that's what it's meant to look like! The one in my set wasn't as bad as the one in yours but it was sufficiently far gone such I couldn't really work out everything about the original appearance.

Even when it's fitted in the set it's not too hard to change the EHT rectifier. I'd wait for John Wakely's opinion on the subject.

Re: Restorers dream part 2 the chassis.
 

Easy enough to change it when it's all fitted, Col.

Re: Restorers dream part 2 the chassis.
 

Leave it in for now. If it's OK, you'll have a spare!!

Cheers,

Steve P.

Re: Restorers dream part 2 the chassis.
 

Looking forward to seeing 'first light' :)

Re: Restorers dream part 2 the chassis.
 

Hi,

Thanks everyone; I'll install the LOPT as it is then and bring volts up slowly with the Variac in the hope of seeing first light as Ian says.

I'm amazed at how the plastic enclosure disintegrated on my set Jeffrey as there was absolutely no sign of it; the entire enclosure had crumbled to fragments which were blown away with the airline; I didn't even know it needed an enclosure until you kindly informed me and sent the pictures; your new enclosure looked excellent and I was about to copy the design which is pretty near the original design so top marks to you.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

You realise Colin, that as you made such a fantastic job of the cabinet, the chassis restoration will have to be up to the same standard because you are definitely not the type to hide the muck under the carpet ;)
Only joking.

Re: Restorers dream part 2 the chassis.
 

Hi,

Many thanks for the compliment Brian; Mike's already suggested a gold plated chassis; I'll be just happy to see a picture to start with because I have a great deal to learn but then I suppose there is no better way than to get stuck in and don't worry about it.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

So THAT'S what an LOPT looks like.

Good to hear you'll soon be getting stuck in as I'm looking forward to reading about it. I'll have to careful though as the vintage wireless bug has well and truly bitten me and I don't want infecting with the TV one.

Good luck, though I don't think you'll need it with your aptitude and the support that's available.

All the best

- Joe

Re: Restorers dream part 2 the chassis.
 

Hi I will pack the spares/ resto set up for you somtime soon and let you know when its packed . But dont forget to connect the crt metal work to deck or you will get a belt from it when you pwer up and the EHT rises. Danny

Re: Restorers dream part 2 the chassis.
 

Hi,

Yes Joe that's what the LOPT looks like from my set and I thought it would be of interest so added the pictures as there are many novices like me just starting out on TV repairs.

Thanks for the kind wishes Joe and I'm afraid you are now a lost soul because you've mentioned TV; this is all I ever did and now there is no way back and no known cure; it won't be long before you have your hands on a TV set.

I'll look forward to hearing from you Danny and thank you for your patience in holding the TV for me also many thanks for the safety warning which I've noted.

I've just put the heating on in the workshop and am about to get my hands dirty before dinner.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

I have a defence: I don't have a television licence! Besides that my house is such a mess at present that I don't think anybody could get one through the door.

- Joe

Re: Restorers dream part 2 the chassis.
 

Hi,

It's only a matter of time Joe; there is no escape however hard you try. It's easier in the long run to just accept your fate and squeeze a telly in.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Hi,

I didn't intend cleaning anything until I had obtained first light but the LOPT area was incredibly dirty and I didn't want to install the replacement LOPT only to have to remove it later in order to clean this part of the chassis.

I was inspecting the chassis closely and wondered about how best to clean without disturbing anything when I noticed the aluminium cover could be removed by unscrewing three hex head self tappers. Now with the cover removed I had better access.

Its amazing how much time simple jobs take to accomplish; I spent over two hours polishing the cover and it now looks much better. The chassis though will never come up well because the plating is in poor condition and to do the job correctly would mean a complete strip which I'm not yet up to doing so I brushed out as much dirt as I could then sprayed with WD40 wiping it dry with a cloth; this hasn't improved its appearance much but at least it is now much cleaner and I can see the individual components; I pulled out two valves and cleaned them and cleaned the valve holders.

I'll take my time and fit the replacement LOPT and assemble everything on the bench coupling the CRT and speaker up then apply a bit of power in the hope of obtaining some response; I doubt very much this will be a quick restoration given what I've seen so far.

Now the milder weather is here I have other more pressing jobs to do around home but will keep working on this chassis as time permits.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Hi Col,
Looking forward to your resto of the chassis. I've started on my TV22 and having read of your cleaning efforts and thought I would share my findings.
I have been using automotive brake and clutch cleaner. You can get it at most car accessory shops in aerosol form. This is great for removing the horrible waxy gunk covering everything. Used sparingly on a cotton bud or tissue you can also clean the individual components and wiring with it. I have used it with a toothbrush and a fine Scotchbrite pad for removing heavier deposits on the chassis. Tagboards clean up great with it too. It evaporates away very quickly and leaves no residue.
Hope this may help.

Best regards

Re: Restorers dream part 2 the chassis.
 

Hi,

Many thanks Howard for the information; I'll buy a can and try it out.

I've been too busy around the bungalow to do any work on the chassis; its rare to have such beautiful weather so I'm making the most of it. The chassis won't be forgotten though because I want to see this TV working.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Hi

With many thanks to a nudge by Andrew (Andrewwausfa) I put the T311 chassis back onto the workshop bench yesterday so hopefully I can resume work on this epic Ekco restoration.

No sooner had the chassis landed on the bench frustration set in. It was a dire day outside with lashing rain and terrific wind on our valley side; the door bell rang and I answered it to a neighbour then got dragged into a car breakdown. An hour later after a soaking and being blown around; I was seated in peace and drying out at the computer when yet another white begging bag (Help the aged) was thrust through our letterbox again distracting me. I did eventually manage to print off all the information kindly given to me by forum members in this thread regarding repairing the chassis. I then spent a while going over the thread to try to pick up where I had left off.

This morning started off very well; I switched on the fan heater and was soon comfortable in the workshop and spent time fitting the LOPT kindly given to me a while ago by Mike (Mikeymushradio). I expected lots of problems because the original LOPT housing had disintegrated to powder breaking a number of the LOPT connections and as this is my first ever TV chassis restoration I felt very much the novice. I was surprised though because fitting the LOPT was relatively easy; two connections were dead easy these being the two valve top caps; the thick screened wire was also easy to solder in place. Two thin wires coming out of the LOPT base were joined to their respective colour coded original wires which I stripped back then added tiny coils using my home made miniature wire winder slipping on heat shrink tubing before soldering then shrinking the tubing using a match. I even think I’ve connected the LOPT correctly which has cheered me up. The U25 supplied with the LOPT was left in place saving more work and I have a spare should this prove to be faulty.

Then I had a “senior moment” I went into the garage to collect the coils I had removed from the neck of the CRT but could not find them. I then checked the front bedroom but still couldn’t locate them neither could I find them in the workshop. I knew they were stored in a margarine container for safety so once again into the garage but they remained elusive; half an hour later I found them grinning at me sitting on top of a large bobbin of winding wire in the workshop where I had placed them out of harms way. I must be losing the plot!!

I had already mounted the CRT into a sturdy wooden frame and as this was large I had to clear both my scopes and other items from the bench end then I carried the CRT from the bedroom and it only just fitted onto the bench as can be seen in the picture. This took care of the morning.

After dinner I had just made a start on the computer as I wanted to have a look at the pictures I had taken of the chassis when yet another white begging bag was thrust through the letterbox (Safetoday). This bag was dumped in the bin and I had just got seated when the door bell rang. Another neighbour was invited in and this time she was enquiring if I would be prepared to reduce the size of a very expensive wooden fireplace that had been imported from China years ago; it only (?) wanted 6” removing from the center then re-joining and made good. She was willing to pay for me to do the work but I politely said I didn’t want the job and I didn’t need the money; I wonder who will be visiting tomorrow?

I find it very hard to settle down on a project as I am constantly broken off which shatters my concentration; I should feel flattered that so many people would like me to do work for them but in reality it is now all becoming very wearing indeed. If I have the time I don’t mind helping anyone out but my neighbours are downright cheeky and seem to think because I have the machinery and a bit of knowledge that I’m obliged to drop everything for them. Being retired is hard work and seven days a week. Sorry if I sound to be moaning but there is no let up living here from all these interruptions.

Now the chassis is back on the bench I’ll stick with it and over the next few days will settle down to working on it; next job is to add the coils onto the CRT neck and connect everything up; I’ll remove the mains cap if present by simply snipping it out; the chassis already looks a great deal better as I’ve tidied it up by blowing off with an airline and polished a few bits of aluminium; I also wiped a lot of the cables with a meths soaked rag this morning as my hands became dirty every time I touched them.

I can’t believe it was April I last touched this chassis but I’m here again and rambling so everything in the world is good.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Nice to know it isn't just my parts and tools which enjoy hiding from me. Start worrying when you're searching for the screw-driver that's in your hand.:)

Glad to see that work has resumed and hopefully you'll be able to crack on before it gets too cold.

All the best

Joe

Re: Restorers dream part 2 the chassis.
 

Without being too far OT ,being friendly with the neighbours is good for one's health according to the Scottish Express!

Possibly not good for restorations though.

David

Re: Restorers dream part 2 the chassis.
 

Welcome back Col, as it's now looking like winter it is time to ge back to the real hobby.
Ed

Re: Restorers dream part 2 the chassis.
 

Well done Col :) I hope you didn't mind my cheeky nudge but I remembered that lovely cabinet and thought it might to be re-united with the chassis.

Disturbances. All too familiar in my house too.

Regards - Andrew

Re: Restorers dream part 2 the chassis.
 

Hi,

Thanks Joe; we are not alone in losing the plot; I can't even put it down to age being only 64.

I totally agree David that it is good to get on with the neighbours I wish someone (Scottish Express?) would tell mine. Some of my neighbours ignore me but are very friendly when they need help.

You are so right Ed; thanks for the welcome back and yes it is already getting cooler in the workshop but as yet the fan heater can get on top of it but not for much longer I fear.

I've made quite a bit more progress this afternoon by fitting all the coils onto the CRT and I realized it didn't have a mains cable fitted so cut a new length and fitted a plug fused at 3A. The on/off switch appeared to be in good condition with a healthy click as it was operated but when I checked for connection with the meter it was O/C on all four tags? I tried and tried but couldn't obtain a reading so removed the switch and found a contact had blown through overload. I took a picture and even made progress with my camera as I found the super macro setting; the switch doesn't bother me too much and will be the next job to sort out then perhaps I can hook up the Variac. I am a bit concerned why the switch blew though so will be watching for signs of stress when power is applied. All in all a good day with plenty more to follow.

Kind regards, Col.

Re: Restorers dream part 2 the chassis.
 

Colin, the switch probably died due to the capacitor that sits across the mains being short circuit.....A common failure!

HTH
Sean

Re: Restorers dream part 2 the chassis.
 

The switch on my T311 was o/c. Just needed operating a few times and a bit of mains to make it work again. If you can get a shot of switch cleaner in there it won't hurt.

Re: Restorers dream part 2 the chassis.
 

Hi,

Many thanks for the nudge Andrew and I don't think it was cheeky so nudge away any-time; thanks for the kind comments and hopefully this TV will be working before too long.

Many thanks for the advice Sean and I will indeed remove the mains cap before applying power; I hope the overload was due to such a simple fault but I'm also concerned as the original LOPT was so badly charred; no doubt the answer will be found once I hook up the Variac.

Many thanks also Jeffrey for your welcome advice. I did operate the switch many times and it had a very positive feel with a good loud click so I expected it to be in good working order. It was only when I used my meter to determine the connections that I could not obtain a continuity reading across any pair of the four tags; I tried lots of times as I thought it rather odd for both pairs to be O/C; I was actually just checking to establish which tag to solder the mains live to.

The picture of the switch shows what I found when I opened it up; the end of one of the strip contacts has been completely blown away by what appears to be an overload hence it would never make contact; I'm still rather puzzled though why there is no continuity between the other two tags but I'll play around with it today and add the results later.

I do appreciate all these suggestions and advice; I've already printed off the long list kindly supplied by John together with other very useful advice supplied by members and will use this to work from.

I'm aware many members reading these notes will too be TV novices and if they move over to TV then perhaps they will find similar mains switch problems. I have experience of working on live radio chassis and in the past have connected power directly to a chassis using a remote switch being very aware of the danger. I am keen to see first light on the this TV but will take my time and have no intention of taking silly dangerous risks to do so and would caution other novices to resist such temptation as it could prove fatal. My first test on power up is always to check if the chassis is live; I have a number of mains connection options these being the usual in series 100W lamp; Variac and also an isolation transformer the circuit is further protected by a 1A fuse. I'd rather be careful and take my time than be sorry.

Whilst on safety and new to TV can experienced members please advise on any danger associated with the CRT covering material as I understand this is live holding the charge for a period even though switched off and if so because I'm working in such close confines with it how is it best discharged? I did say I would be asking all the silly questions but this is how I learn. Thank you for your patience.

It's time I did something useful like sorting out the switch.

Kind regards, Col.