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1971 Beovision 3200
Forum Free Registration Closed
Granada Television Brochure, 1970s
Long Gone UK TV Shops
Memories of a Derwent Field Service Engineer
PYE Australia Circa 1971
Radios-TV VRAT
Fabulous Fablon
Thorn TX10 Chassis
Crusty-TV Museum, Analogue TV Network
Philips N1500 Warning!
Rumbelows
Thorn EMI Advertising
Thorn’s Guide to Servicing a VCR
Ferguson 3V24 De-Robed
Want to tell us a story?
Video Circuits V15 – Tripler Tester
Thorn Chassis Guide
Remove Teletext Lines & VCR Problems
Ceefax (Teletext)
Suggestions
Website Refresh
Colour TV Brochures
1970s Lounge Recreation
CrustyTV Vintage Television Museum
Linda Lovelace Experience
Humbars on a Sony KV2702
1972 Ultra 6713
D|E|R Service “The Best”
The one that got away
Technical information
The Line Output Stage
The map
Tales of a newly qualified young engineer.
Tales of a Radio Rentals Van Boy
Sanyo SMD
Disastrous Company Rebranding
1969 Philips G22K511
Memories Of The TV Trade
Crazy house
Dirty TV screens
Dual Standard and Single Standard CTV’s
Radios-TV on YouTube
The Winter of 62/63
A domestic audio installation
1979 Ferguson Videostar Deluxe 3V16
Music centre modifications
Unusual record player modification
B&K 467 Adapters
Mishaps In The Trade
1971 Beovision 3200
Dick Smith FBT Tester
I needed to test a modern diode-split LOPT and while looking for a suitable tester found this one of Australian origin
A simple circuit, and I had most of the parts required, another google search found a ready made veroboard layout too, this had a few errors and could probably be a bit neater, but it saved time so I built the circuit;
I tried it with a new old stock LOPT which showed good with all LEDs on, then I added a shorting turn (green wire) which extinguished all but one LED (bad reading)
I can't comment on the efficacy of this unit, as I've not got a good selection of good and faulty transformers to test it with, but it is so simple to build and understand the operation, it seems like a worthwhile little project. It could also be used with SMPSU transformers, scan coils and other wound components.
There's been a number of circuits produced over the years, the other day I found one in an 80's Television mag, can't remember what year now. I've a similar unit made by Jabco and did a post a while back here. Like yours it seemed to confirm shorted turns and I've used it when testing other LOPTs since.
Any plans to house yours in a project box?
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Yes, I've been looking for a case, I don't know if it's just me, but it always seems that Hammond or Verobox style cases are either a few mm too small or twice as big as I need to house the circuit I've built...
I was looking at the Television mag tester too, but it had a good/bad indication, I like the bargraph system with this one.
In the late 90s -early 2000s when I used to repair lots of VGA CRT monitors, I used to use I yellow (Promax?) LOPT tester which you attached the EHT cap to and gave a good/bad indications, it worked at 32kHz, that has long since disappeared and I've not seen another since and I don't know if there was a 16kHz version for TV transformers.
Once it is in a case I'll post a photo.
I think I have one of those yellow ones, but it's branded H R Diemen - the people who used to make the pattern line transformers. I did build the Television design from the mid-80s too but I like the Dick Smith one - I bought all the bits, but have never built it.
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