View Single Post
Old 17th Sep 2011, 4:30 pm   #171
Retired
Heptode
 
Retired's Avatar
 
Join Date: Mar 2009
Location: Fenay Bridge, Huddersfield. UK.
Posts: 673
Default Re: Restorers dream part 2 the chassis.

Hi,

Thanks Jeffrey I’m glad I didn’t blame the Poundland batteries too much; the 250mA drain explains their quick demise.

Thanks also Mark; please see the following.

Thank you Mike for adding your technical explanation of what you did yesterday; there is a huge gap between our knowledge of TV work; Yes it was a pity you had to leave because we enjoy your company and it wasn’t a problem at all that you could not finish off as it left me something to do and a bit more to learn. You moved me on light years and I was delighted when the test card did flash up so knew the set wasn’t far off working.

I don’t know why I bother going to bed sometimes as I was wide awake again in the middle of last night this time thinking about my life in general. When I made my first enquiry about TV and received lots of replies a caring friend thought I was being dragged into TV work against my will as to be honest I had absolutely no interest in TV other than I had seen a really rough looking TV cabinet in The Bulletin.

What have you all done to me? During this chassis restoration I felt as though I was living in virtual reality but last night I came to the conclusion I’m in fantasy land. It took four months work to restore the cabinet and I had a clue about how to do that but this chassis is different. It’s only about a fortnight ago that I had never tried to work on a TV chassis but here I am confidently re-installing a channel selector drum having not removed it myself; I’ve drawn 1” long EHT lightning from a U25 and lived to tell the tale and I’m slowly finding my way around the chassis. In two weeks from wreck to showing a test card; it would have taken me longer but Mike helped a great deal yesterday although I believe had I changed as I planned to do the 0.1uF cap inside the tuning unit as described by John the test card should have appeared? What I did learn from Mike was his approach and it was a pleasure to watch his technique at problem solving; credit to Mike for helping and it was Mike who got the first glimpses of the test card to appear not I.

This is not just a radio forum I think its open university. Really top class experts and very decent guys have helped me considerably on a one to one basis by taking me by the hand and explaining in great detail each stage in such a way that even a novice like me could understand and the results speak for themselves. None of the overbearing health and safety issues just simple instructions on what I should avoid to prevent receiving an electric shock and I was more than happy to get stuck in. Jeffrey not only gave excellent information but kindly donated two U25 valves and now John has also informed me that he is not only donating a PY32 valve but even has a suitable channel knob and is to post both on to me. I feel truly humbled by what has happened to me over the last couple of weeks and offer my most sincere thanks to everyone concerned.

My friend was indeed correct; I’ve been drawn in to TV restoration work and how can I return to radio work now after seeing a picture come to life the way I did; I’m doomed.

I was in the workshop by 8.30 this morning raring to go and spend the day on this chassis. I’m sorry guys but hanging an Aurora on with a bit of old wire is just not my style. First thing I did was to tidy up as the bench looked like a bomb site. I moved everything to its proper place then searched for a reliable 9VDC supply for the Aurora and found a really nice PSU fully variable up to 30V so coupled this up and I also made a neat job of adding proper coaxial cable; I double checked the voltage was indeed 9V before switching on. Yes shame on me for being so tidy and neat.

Now I was happy and settled; next job was to check around before re-fitting the selector drum and I noticed another cap that I thought worth changing whilst the drum was out and it was tucked well out of the way; I couldn’t make out what it was so just snipped it out leaving a pair of ¼” long tails to solder the new cap to. Big mistake: it proved to be a 2uF high voltage cap and I didn’t have a new one so had to spend time re-fitting it.

I polished all the drum contacts and the connection fingers using Solvol Autosol then had a go at installing the drum. Mike had told me to watch out for the spring loaded lever at the top of the enclosure and at this point I realized I needed at least three hands; in the end I propped the lever up by simply placing a nut as shown in the picture taking care of that problem. It was still rather a struggle to get the drum home and the retaining spring clips into place but I managed; Mike had also told me which way the drum went in because it is so easy to install it 180 degrees out. I then remembered to remove the nut and re-fitted the covers.

Now for the moment of truth and I switched on; I also switched the Aurora on and waited; at first there was all sorts of rubbish on the screen but after a lot of knob twiddling at last the test card was showing and stationary; it wasn’t perfect as the height was and still is way off but the picture show how good it is at this stage and to me it is very good to say the set has been asleep for many years.

Our climate is wonderful; I had a choice of taking the test card pictures through the workshop window either in a downpour of rain or brilliant sunshine; I took a total of fourteen pictures just to get a decent one as shown. Just as I had done this Bron came to me rather upset saying there was an injured pigeon in the back garden. A couple of hours later we were back home after a visit to the vets. On arrival at the vets the pigeon had died during the journey there but at least it died amongst friends and not alone. We were both sad because we like all the wildlife that visits us.

After dinner I changed the remaining two wax caps; one was on the height control but when I checked there is still a problem with the picture height; twiddling all the knobs I can obtain picture height but then everything becomes grossly distorted with a rolling picture of sorts.

I’ve still some way to go but from wreck to a test card in two weeks is beyond my wildest dreams. Please note all other novices contemplating tackling a TV restoration; don’t do it; run away before you too are doomed like me.

Kind regards, Col.
Attached Thumbnails
Click image for larger version

Name:	Drum..jpg
Views:	212
Size:	91.3 KB
ID:	56315   Click image for larger version

Name:	Nut in place..jpg
Views:	217
Size:	162.4 KB
ID:	56316   Click image for larger version

Name:	Much tidier..jpg
Views:	224
Size:	102.5 KB
ID:	56317   Click image for larger version

Name:	Test card..jpg
Views:	237
Size:	191.2 KB
ID:	56318  
Retired is offline