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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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3rd Jun 2007, 12:22 pm | #1 |
Rest in Peace
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TrueVue A33 Portable - assistance requested
Good morning!
Oh the joy of a new set on the bench! I have just acquired this little receiver which I hope might go some way to curing my current obsession with Pye equipment. Does anyone please know anything about these? I can only find a brief reference on Jon Evans' website and nothing else. The design is obviously economical, using 13 valves and a GEC 6505A 9" round CRT (aluminised, but no ion trap) plus 2 metal rectifiers. EHT is derived from the lopt, there is no boost diode and the line output valve is a KT36. The set appears to be a TRF, but I haven't delved very deeply into it yet. Anybody know anything? I have (I hope) attached some photos. Regards to all, Dave |
3rd Jun 2007, 5:29 pm | #2 |
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Re: TrueVue A33 Portable - assistance requested
OK! OK! . I should've searched the Forum first!
I've now found last year's thread, but I'm no better off. I'd still appreciate it very much if anyone has any info at all. Dave |
4th Jun 2007, 11:42 pm | #3 |
Heptode
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Re: TrueVue A33 Portable - assistance requested
What a lovely little set! Never seen one of them before.
It looks really rather "compact" which no doubt will make it an absolute pain to work on. ...and for goodness sake, don't drop that rose tinted glass panel! Afraid I don't know anything about this one, but I'll certainly be watching this thread with great interest. |
5th Jun 2007, 8:26 am | #4 |
Octode
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Re: TrueVue A33 Portable - assistance requested
Any chance of a photo for the website ?
Also, are there any dates printed on the various electrolytics ? I see there is at least one Mullard valve but are they mostly GEC valves ? TTFN, Jon |
5th Jun 2007, 9:34 pm | #5 | |
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Re: TrueVue A33 Portable - assistance requested
Quote:
Jon: You can have some photos with pleasure, perhaps you can advise the best way to send them to you. I note the smallish file size available for Forum pics. I'll do some good ones at the weekend, with background free from work bench clutter! The only electrolytic with a date, so far as I can see is an 8mf in the line timebase. This carries the date of Oct 50. The main thing exercising my mind at present is the fact that the heater voltages add up to 125.9v, but there is no dropper resistor! Also there are two metal rectifiers, connected in parallel, but only one is apparent in the photos in last year's thread, together with a pair of hefty droppers. The valve line-up consists of 6 x Z77, 1 x D77, 3 x N37, 1 x 12AU7 and a KT36. All are GEC except the single EF91 (presumably a replacement) and the 12AU7 (Brimar). Regards, Dave |
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5th Jun 2007, 10:25 pm | #6 |
Heptode
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Re: TrueVue A33 Portable - assistance requested
Hi
Yes, I have one of these sets, and yes, no dropper in there. It has the dreaded resistance mains lead, like some old radios. Mine hasn't got its lead, it's been cut off, but I read about it in a Practical Television mag in the "Problems Solved" bit. Danny Last edited by Mike Phelan; 19th Apr 2008 at 4:50 pm. Reason: Readability |
6th Jun 2007, 8:59 pm | #7 |
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Re: TrueVue A33 Portable - assistance requested
Spot on Danny!
I've never seen a line cord on a TV before, but there it is - the set has its original lead - the fact that it's nine feet long might have eventually given me a clue! It'll have to go though; I've asked PWH if he still has any of the braided cable he had made up. This should make a realistic replacement. I think I might incorporate a silicon diode in the heater chain as was done in the 60s and achieve the voltage reduction that way. Can you think of any reason why that would not work? Regards, Dave |
6th Jun 2007, 9:08 pm | #8 |
Octode
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Re: TrueVue A33 Portable - assistance requested
I've never done it on a tv before, though I have done it many times on radios without problems, and can't see any reason why it would not work on a tv, but then again I am not an expert.
Just remember a tv pulls more current than a radio, so make sure the diode is suitably rated: you may also need a small dropper to make everything add up. What about a capacitive dropper? That should work and there's a calculator for that round here somewhere. Jay
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The light at the end of the tunnel is probably the headlight of an oncoming train Last edited by Mike Phelan; 19th Apr 2008 at 4:53 pm. Reason: S&P |
6th Jun 2007, 9:21 pm | #9 |
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Re: TrueVue A33 Portable - assistance requested
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6th Jun 2007, 11:00 pm | #10 |
Heptode
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Re: TrueVue A33 Portable - assistance requested
When I get around to my set, I intend to use a dropper fitted inside.
Before you start, check the crt gettering, as these tubes tend to be soft. My set has had a different tube fitted! Danny |