|
Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
|
Thread Tools |
7th Apr 2019, 4:49 pm | #1 |
Octode
Join Date: Feb 2010
Location: Leicester, UK.
Posts: 1,431
|
Bush TV12
Hi all,
it's about time I opened a thread on this set being as it is now taking over my life I purchased this little old TV12 a couple of months back. I restored a TV22 a few years back but I ended up getting rid when having to clear some space, from then on I regretted it and spent a long time waiting for something suitable to pop up. Anyway this one came up, it wasn't too far away from me, a one family owned from new set and it looked to be in fairly good shape, or so I thought. At first glance the set looked quite good, no chips or cracks but matted with dirt, quite usual for an unrestored 'as found' set of this age. Once removing the back cover I was in for a real treat. This set is in a sorry state, in fact if this had been a 'woody' I doubt it would have survived. There is corrosion EVERYWHERE, the poor thing has been quite badly neglected and stored in damp conditions for a very long time. All of the EF50 sockets in the top deck have corroded to the point that the tags are falling off, every transformer is caked in rust as is the speaker and, in fact, anything that is made from steel. This weekend I have really started making some progress though. After poking around with the meter all the transformers and chokes test okay so I declared it worth-while to actually work on... To be honest, if it wasn't a TV12 I think it would have been only worthy of scrap with the condition it is in. I removed the casing to the line transformer and the smell was awful, the foam padding had absorbed a lot of moisture over the years and I just knew then that the Line tx would be O/C or short, a test with the meter confirmed that it is indeed O/C so a re-wind is in order for that one. So gradually I have been stripping this down, making lots of diagrams and taking plenty of photos. I've really been burning the midnight oil on this one and we are nearly there, I decided to take a break and write this just to give myself some time off! As you can see by the photo there is a lot of rusty powder just from moving it around and taking nuts and bolts off, this is actually the third time I have vacummed the bench and it is still caked in it. This is going to be a proper rebuild, each part cleaned, repainted if necessary and gradually re-assembled. Luckily all of the aluminium has survived with little corrosion other than the top deck, which I may actually have reproduced as it is in an awful state on the top. This will be a bit of a slow thread but I thought I would share with everyone what a mess this set is. I've attached some photos just to give you an idea of the poor condition, although I have to say they seem to sweeten it up a little bit than show its true state... I've seen worse for sure but this has really suffered! |
7th Apr 2019, 5:32 pm | #2 |
Dekatron
Join Date: Nov 2009
Location: Lincolnshire, UK.
Posts: 4,990
|
Re: Bush TV12
It is a bit rusty in the places you'd expect it to be with the way these sets are normally stored in a damp loft or shed, but I don't think it's actually too bad from the looks of it in your pictures. I don't see why you need to have the top deck re-made, it looks perfectly salvageable to me.
|
7th Apr 2019, 5:46 pm | #3 |
Octode
Join Date: Feb 2010
Location: Leicester, UK.
Posts: 1,431
|
Re: Bush TV12
Yes I'd say it was stored in some kind of out building for a long time from the condition. I think the photos have been very kind to the set, it is very poor in person and the more I've dug into it there is a lot of corrosion.
The top deck didn't look to bad at first glance either but all the steel parts that have been attached to it have really reacted with the ally and as I have stripped it down there are huge craters of powedered mess all over it that seem to have no end. I am going to skim it and see how it looks after that, then I'll decide if it can be smoothed out and painted. I would prefer to keep what is there myself but there are some really bad areas on it. All of the aluminium it to be painted just to help with the appearance of the chassis although I will probably stick with a silvery colour to be faithful to its original look. |
8th Apr 2019, 9:24 am | #4 |
Dekatron
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
|
Re: Bush TV12
It looks good to me. Any attempt to remanufacture the chassis will end in a disastrous mess! Far better to just clean it up, clean the rust off the steel parts and paint them black. Dirt,and muck won't stop it working.
A good aluminium cleaner is diesel and an old tooth brush wiped off with a rag as you go. If you pull it apart the chances of getting it working again will be reduced. Is it a London or Birmingham model? A disc around the aerial socket will reveal it's origins. It is a fix tuned TRF receiver unit. I would make an attempt to get it working as it is then work on small areas powering up as you go. Just my method. John. |
8th Apr 2019, 1:53 pm | #5 |
Octode
Join Date: Feb 2010
Location: Leicester, UK.
Posts: 1,431
|
Re: Bush TV12
Yes I agree, it will not be easy to have a good replica of the top chassis made and I would like to keep its original metal so I will try my best to spruce up this one, there are some areas of real heavy corossion on it though. The sides and front are all in good order luckily, I think the years of dust has held on to any moisture it absorbed and damaged the surface of the top.
I understand that it makes the project a whole lot more difficult with stripping it down but it is really looking sorry in places and I decided to go whole hog and just do a proper ground up restoration on it. I have many carefully drawn diagrams and photos showing each component and its associated wiring with details of removal. This will be carefully followed when re-assembling along with the schematic, and I will be metering all wires and connections throughout the circuit to ensure it is as it should be during the rebuild. I normally stick to a similar method when repairing these old sets, but there is just so much wrong with this, corroded pots, stuck switches etc and with the overall condition I thought this is really how I should tackle this one and make a good job of it whilst doing so. It is a Sutton Coldfield set, and a date stamp on a cap suggests it was manufactured around Feb 1950 |
8th Apr 2019, 2:39 pm | #6 |
Banned
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 3,897
|
Re: Bush TV12
Nah, it will be fine, lick o' paint here, green sticker here, another lick o' paint.................. I'll ask, don't get upset, how's the tube?........
|
8th Apr 2019, 3:18 pm | #7 |
Octode
Join Date: Feb 2010
Location: Leicester, UK.
Posts: 1,431
|
Re: Bush TV12
Hi Sam,
Funny you should ask that actually! It's not good, as can be seen from the attached photo it has taken a good whack to the base. I know the set was used into the 70s too so it had quite a life and I'm sure this is the original CRT. I have checked the continuity of the heaters and they are fine, there is no heater cathode short either that I can measure so from these tests it's not a certain dud but as for emissions we will have to wait and see. I do have a couple of scrap sets in the loft from this era so a replacement should be easily sought if the worse happens |
8th Apr 2019, 4:10 pm | #8 |
Dekatron
Join Date: Jul 2008
Location: Charmouth, Dorset, UK.
Posts: 3,601
|
Re: Bush TV12
Makes me feel my age, I remember these sets when they were nearly new.
|
9th Apr 2019, 8:39 am | #9 |
Dekatron
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
|
Re: Bush TV12
Oh Peter, Bless!
The tube looks OK providing it has a getter. probably a MW22-17 or 18. Power supply first then line output stage to see what condition the LOPT is in. This chassis struggles to produce a steady 5kv so it is well worth drying out the LOPT overwind [passing a current through it] for a few days. The RF unit is a beauty, very military in construction. No nasty wax decoupling caps, all silver mica moulded types. The EF50 valve pins and spigots will require very thorough cleaning and light lubrication. The pins will be black! Get it 'working' first, then do your' housework' on it later. Good luck with it, they are a simple circuit and work well. John. |
9th Apr 2019, 8:55 am | #10 | |
No Longer a Member
Join Date: Oct 2016
Location: Maroochydore, Queensland, Australia.
Posts: 2,679
|
Re: Bush TV12
Quote:
Mine required all new wiring valve sockets and most components. I had the rusty steel parts electroplated, but because of the pitting where the rust was they were also silver-grey painted. A good hookup wire (for a hot running set) is the silicone rubber covered medical instrument grade wire from RS, its insulation does not retract with soldering and it looks like old fashioned wire. I'd go for all new sockets in most cases, preferably ceramic. Here is an article on mine, it was an awful lot of work, but worth it in the end: http://worldphaco.com/uploads/BUSH_TV22.pdf |
|
9th Apr 2019, 2:14 pm | #11 |
Heptode
Join Date: Jun 2006
Location: Ware, Hertfordshire, UK.
Posts: 988
|
Re: Bush TV12
I've got a TV11A (the wooden version of the TV12A) that I restored many years ago.
I purchased it at the NVCF. The seller had re-varnished it, fairly well, but that had hidden the damp damage. In fact the cabinet started to fall apart before I made it back to the NEC car park! After restoring the set it worked well for a while before the frame transformer started to fail. Now working with a frame transformer from a GEC BT2147 (original transformer re-wound and waiting to go back in), but the line transformer is showing signs of distress (fluctuating width). So these are the sort of nasty faults you might encounter with a set that has been damp. The frame output and line output transformers are easy to rewind. The tiny EHT transformer that sits on top of the line output transformer has to be wave wound, but, it is usually ok. However, these sets were well made and can perform very well when restored. Cheers Andy
__________________
www.youtube.com/user/andyvalve100 |
9th Apr 2019, 6:31 pm | #12 |
Dekatron
Join Date: Mar 2008
Location: Worthing, West Sussex, UK
Posts: 5,185
|
Re: Bush TV12
My TV12 was also in a sorry state, it had a broken CRT and had also been badly stored so there was a fair bit of rust & corrosion to the aluminium chassis.
But despite all that it it turned out to be a great little set, so don't be too concerned about it's present state. see here: https://www.vintage-radio.net/forum/...d.php?t=122824 Good luck with your restoration. Mark |