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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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15th Jul 2020, 8:11 pm | #1 |
Diode
Join Date: Jul 2020
Location: Keith, Banffshire, Scotland, UK.
Posts: 8
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Bush TV22
Hello.
I'm attempting to restore a Bush 22 set and so far have given the set a thorough clean and replaced all suspect or brittle wiring as well as wax capacitors and cleaned the old pitch from the LOPT using the white spirit method. Everything visually looks OK with no broken wires or damage. I have no testing equipment as such but have powered the set up, all valves light up including the PL38 which gives a quite bright purple light. The EY51 which I replaced with a new old one, is still not lighting up. Could anyone advise what steps I should try next any advice would be welcome. Regards, John. |
15th Jul 2020, 10:03 pm | #2 |
Moderator
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Location: Ipswich, Suffolk, IP4, UK.
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Re: Bush TV22
The TV experts will be along shortly, but I think you'll find it difficult to get this set working without a test meter (DMM) at the very least.
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Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
15th Jul 2020, 10:40 pm | #3 |
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
Posts: 7,549
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Re: Bush TV22
For a start, the PL38 should not have a bright purple light. That suggests the valve is gassey and needs replacing BUT as already suggested there is NO POINT in poking and hoping without at least a testmeter to check the operation of the line oscillator and boost rails etc otherwise a new valve could be destroyed in a very short time if there is a more serious fault. There might be a short somewhere in the line stage that is causing severe overload of the PL38. A bright purple glow suggests ionisation inside the valve which is not good.
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16th Jul 2020, 12:05 am | #4 |
Dekatron
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Re: Bush TV22
Hi John you are in the right place, a very supportive Forum and I know relatively little about TV's myself but it's probably not a good idea to open separate threads. The first one was about a Band 3 Convertor for the TV22. The second about you working on the set without any test equipment
This is a very popular make of TV, to say the least and there are lots of threads detailing every aspect. I think it would assist the really expert and helpful people here if you could say a bit more more about your own background/experience. You indicated that you are "very much an amateur in this field" but maybe you do have other electrical experience? As others suggested, it's a bit unusual to have no test gear! We just don't know where you are coming from I hope that helps you! Dave W Last edited by dave walsh; 16th Jul 2020 at 12:19 am. |
16th Jul 2020, 5:19 pm | #5 |
Hexode
Join Date: Dec 2011
Location: Wigan, Greater Manchester, UK.
Posts: 291
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Re: Bush TV22
Before doing anything. Buy a multimeter! A useful one can be obtained for under £10. You also need a circuit diagram for the correct model I think TV22 comes in three designs.
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18th Jul 2020, 11:21 am | #6 |
Heptode
Join Date: Jun 2006
Location: Ware, Hertfordshire, UK.
Posts: 988
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Re: Bush TV22
Hi John,
To identify the chassis in the TV22, you need to know:- If the line output valve is a PL38 or a PL81 (you have stated it is a PL38, so that gets us somewhere). Is the line output transformer on the left or the right of the chassis (when viewed from the rear) Whether the RF deck below is populated with EF91s, EF80s. The results would mean:- PL38 + EF91, line op on right = TV22 mark 1 PL38 + EF80, line op on right = TV22 mark 2 PL81 + EF80, line op on right = TV22U PL81 + EF80, line output on left = TV22A Cheers Andy
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18th Jul 2020, 11:30 am | #7 |
Dekatron
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Re: Bush TV22
I certainly would not have applied the mains to the set till at least certain capacitors are replaced.
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19th Jul 2020, 5:50 pm | #8 |
Diode
Join Date: Jul 2020
Location: Keith, Banffshire, Scotland, UK.
Posts: 8
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Re: Bush TV22
Thank you all for your help. I have obtained a multimeter, I had replaced all the wax capacitors on the receiver deck and most on the main deck and also changed the ones on the timebase panel, as well as replaying most of the wiring which was brittle and cracking. Andy, thats helpful info, so we have a mrk 2 tv. I have a service manual for tv 22 which has also been helpful. Now making some headway. Thanks again for all you help,
regards, John. |
7th Jan 2022, 5:46 pm | #9 |
Diode
Join Date: Jul 2020
Location: Keith, Banffshire, Scotland, UK.
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Bush TV22 picture issue.
Hello,
I now have a picture and sound on the Bush 22 TV after undertaking refurbishment of valves, capacitors, resistors, wiring and replacement of badly burned line out board. I'm using a Hedgehog converter but having a problem with dark vertical bands which are more prominent on the left side of the screen and roll from top to bottom. I'd be grateful for any advice on what could be causing this or suggestions on how to remedy this, regards, John. |
7th Jan 2022, 7:38 pm | #10 |
Dekatron
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Location: Kilmarnock, Ayrshire, UK.
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Re: Bush22 TV picture issue
Hi
There is a trimmer on the scan coils, this needs adjusting most likely. A picture would help diagnoses though
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8th Jan 2022, 8:47 pm | #11 |
Diode
Join Date: Jul 2020
Location: Keith, Banffshire, Scotland, UK.
Posts: 8
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Re: Bush22 TV picture issue
Hello Trevor,
many thanks for responding to my question. I have a photo hopefully attached. I've not yet had time to try adjusting the trimmer but will get around to it very shortly. It seems that the lines are rolling in both directions. regards, John. Last edited by View-master3d; 8th Jan 2022 at 8:50 pm. Reason: added text |
8th Jan 2022, 11:23 pm | #12 |
Dekatron
Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
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Re: Bush TV22
I have never seen that on a TV22 or in fact any tv. Most odd effect. Could you have made a mistake when replacing your rotten connecting wires? Just a thought. John.
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9th Jan 2022, 10:43 am | #13 |
Diode
Join Date: Jul 2020
Location: Keith, Banffshire, Scotland, UK.
Posts: 8
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Re: Bush TV22
Hi,
thank you for replying, it could be a possibility though I am very careful to replace like for like with the wiring and mark the spot when changing, I also like to take a photograph just to be sure, but , as with anything I could have made a mistake so worth looking at it again, many thanks, John. |
9th Jan 2022, 12:51 pm | #14 |
Nonode
Join Date: Feb 2005
Location: Worcestershire, UK.
Posts: 2,525
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Re: Bush TV22
An oscillation like this looks to me like a connection somewhere is probably wrong or not made, as John says. It could also be a 'bad earth' somewhere.
The first thing I would do is to check the connections to the sync and video output leads to the RF shelf (6 and 7 on service sheet 1091) are made properly, the correct way round, and the wires not pulled out under the insulation. They can get damaged when you're fiddling about. Failing this, I would gently waggle all the valves in their holders, particularly on the RF shelf, being especially careful you don't touch any live parts by mistake! Otherwise, it's down to exhaustively checking all the joints you have made are correct - and not dry. Good luck. Steve
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9th Jan 2022, 2:18 pm | #15 |
Dekatron
Join Date: Sep 2006
Location: Kilmarnock, Ayrshire, UK.
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Re: Bush TV22
Hi.
Certainly not the trimmer adjustment on the scan coils. Looks like some form of instability, pick up from the line stage. Should be traceable on the oscilloscope I'd say. Does it alter with contrast adjustment or tuning?
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10th Jan 2022, 11:57 pm | #16 |
Diode
Join Date: Jul 2020
Location: Keith, Banffshire, Scotland, UK.
Posts: 8
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Re: Bush TV22
Hello everyone,
thank you all for taking the time to advise me. I spent this morning with the TV apart again, went through all the wiring ( all seemed fine). I found one of the two capacitors that sit on the top deck was not attached at one end and the metal band that holds the tube in place had slipped back down the tube, that may have happened as i pushed it back into the casing. I then gave the set a good tune and checked out connections etc on the hedgehog, i then got a much better picture without the banding. Many thanks again, John. |