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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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19th Oct 2020, 9:57 am | #41 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,916
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Re: Dicey Decca CTV25
Well done - that fault was a bit unfair!
That presentation looks a lot nicer than the more ordinary door-free CTV25. |
19th Oct 2020, 10:21 am | #42 |
Nonode
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Location: 1966-1976 Coverack in Cornwall and Helston Cornwall. 1976-present Bristol/Bath area.
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Re: Dicey Decca CTV25
Great work Mike. having the same fault on two sets of scanning coils is one hell of a coincidence.
Do they just use one 4.7M resistor in the focus circuit, most hybrid sets had two such resistors. I will have to dig the circuit out when I get home from work.
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Simon BVWS member |
19th Oct 2020, 1:13 pm | #43 |
Octode
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Location: Solihull, West Midlands and Beaford, Devon
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Re: Dicey Decca CTV25
Hi Trevor, Gary, Glyn and Simon.
Thank you for your kind replies. Re the coils - Yes, it was a little unexpected to say the least. I've made a start on the other bits and bobs but alas the 625/405 solenoid has melted, jammed the plunger in place and gone open circuit so another solenoid is required. If I can find one then some kind of fusible circuit may be in order to protect it from jamming again. I have a vague feeling that it might be the same as that used in the Philips G6* - not that that's really much help in finding one, although it increases my chances a little. It's the kind with the flip-flop switch on the end to turn off the power once it has been fully engaged. I'll report my progress. Thanks all. Kind regards. From Mike. *Edit. Oh dear, I've just checked and it's not the same. Never mind...
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G7TRF Last edited by Mikey405; 19th Oct 2020 at 1:29 pm. |
20th Oct 2020, 12:41 pm | #44 |
Dekatron
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 6,916
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Re: Dicey Decca CTV25
...and here was I about to offer you a G6 convergence solenoid.
Pre-Bradford Deccas were very unusual visitors to the workshop - probably as they were around twelve years old by the time I started! |
20th Oct 2020, 1:22 pm | #45 |
Octode
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Location: Solihull, West Midlands and Beaford, Devon
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Re: Dicey Decca CTV25
Thank you for the kind thought Glyn. I'll take a photo of the solenoid in case anyone might have one. It has a square "peg" on each end with a hole drilled to attach to the switches of the IF and line timebase panels and a 47R resistor underneath.
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G7TRF |
20th Oct 2020, 1:29 pm | #46 |
Dekatron
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Re: Dicey Decca CTV25
I like it. That cabinet is almost big enough to appeal to the american market
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Kevin |
20th Oct 2020, 2:18 pm | #47 |
Octode
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Location: Solihull, West Midlands and Beaford, Devon
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Re: Dicey Decca CTV25
Hi Kevin.
Yes, it is a bit of a behemoth - I used to have an identical one in a dark Rosewood cabinet many many years ago but I think I prefer this lighter-coloured model. In case anyone might happen to have a spare, here's a picture of the melted solenoid. I guess it could be rewound and repaired but I think it has melted the plunger and plastic former so likely not really worth all the bother. Thanks Kevin and everyone. Kind regards. From Mike.
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G7TRF |
20th Oct 2020, 2:47 pm | #48 |
Dekatron
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Location: Warnham, West Sussex. 10 miles south of DORKING.
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Re: Dicey Decca CTV25
If all else fails, from the picture it appears to have a lot in common with the Thorn 950/1400 series solenoid. John.
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20th Oct 2020, 3:43 pm | #49 |
Nonode
Join Date: May 2007
Location: Redruth, Cornwall, UK.
Posts: 2,573
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Re: Dicey Decca CTV25
Hi Mike.
I found one in a box of spares in the garage, see attached pics. It looks to be the same solenoid. I've checked that the plunger moves freely and the windings seem fine. Yours for the cost of the postage. PM if interested. Regards, Symon. |
20th Oct 2020, 4:14 pm | #50 |
Octode
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Location: Solihull, West Midlands and Beaford, Devon
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Re: Dicey Decca CTV25
Oooh. That looks like the very one Symon. Thank you. I will indeed send you a PM.
Kind regards. From Mike.
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20th Oct 2020, 7:49 pm | #51 |
Heptode
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Location: Coventry, West Midlands, UK.
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Re: Dicey Decca CTV25
my paternal grandparents had one of these sets and I wish I had known when they wanted to get rid cos I would have loved it. The sound was superb I have no idea what the speakers were that were used in it
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20th Oct 2020, 8:08 pm | #52 |
Nonode
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Location: Redruth, Cornwall, UK.
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Re: Dicey Decca CTV25
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20th Oct 2020, 8:34 pm | #53 | |
Heptode
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Location: Ware, Hertfordshire, UK.
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Re: Dicey Decca CTV25
Quote:
How about a mains rated polyswitch that is rated to trip just below the solenoid operating current? The solenoid will switch itself off before the polyswitch trips. I used the same idea in one of my strowger demo exchanges to protect the release magnets, much nicer than using heat coils. Cheers Andy
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21st Oct 2020, 5:10 pm | #54 |
Octode
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Re: Dicey Decca CTV25
Hi Andy.
That's a very good plan and I shall look into that. They're pretty clever those devices. What I was thinking was a time-based protection with a short R/C circuit to trigger a small transistor and then a relay to remove the earth return but your idea sounds like a much more elegant solution. I shall investigate further. Thanks Andy. Kind regards. From Mike.
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G7TRF |
23rd Oct 2020, 12:24 pm | #55 |
Octode
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Location: Wimborne, Dorset, UK.
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Re: Dicey Decca CTV25
Hi Mike,
I've just caught up with this, I have to say that the set looks very nice, well done on finding that fault with the soldering on the coils, that would have driven me around the bend! As Tas said, excellent detective skills! All the best old mate.
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Lee |
23rd Oct 2020, 12:45 pm | #56 |
Hexode
Join Date: Nov 2010
Location: Sheffield, South Yorkshire, UK.
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Re: Dicey Decca CTV25
Well done Mikey, all the cumulative years of knowledge, experience, fault finding, repairs on this forum, and we’re still learning...
Regards, Alan. |
24th Oct 2020, 10:02 am | #57 |
Octode
Join Date: Jul 2006
Location: Solihull, West Midlands and Beaford, Devon
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Re: Dicey Decca CTV25
Thanks Lee and Alan for the kind comments.
Well, thanks to Symon (Philips210) I now have a nice new (well, new-to-me anyway) solenoid for the Decca. I'm currently at work (listening to our own Steve James - Colourstar - playing test-card-friendly music on Serenade Radio) but I'll get the solenoid soldered in (and clean and free the system switch) this evening and report back. Thanks all. Kind regards. From Mike.
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G7TRF |
24th Oct 2020, 11:02 am | #58 |
Nonode
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Re: Dicey Decca CTV25
Hi Mike.
That's great, I am pleased it arrived safely. I have the other solenoid which I think is for the convergence box and parts of the system switch. When I find a suitable box, I'll drop them in the post F.O.C. Regards, Symon |
24th Oct 2020, 2:32 pm | #59 |
Octode
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Location: Solihull, West Midlands and Beaford, Devon
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Re: Dicey Decca CTV25
Thanks Symon. That's very kind of you. I'll report back once the solenoid is fitted.
Kind regards. From Mike.
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