Thumbing through a staff Telepart magazine from August 1980, I found these two interesting (to me) ad's.
If only A ! ........
Quote
Thick Film is a refinement in the continuing process of integration and miniaturisation. It is more reliable, simpler, functionally more efficient..............
Thorn LOPT; "Magic Circle" mod.
I've only ever heard of how bulletproof Thorn LOPTS were, so it was intriguing to read about the portable lopt problems, and the fix. Not heard of this before, has anyone else?
And Finally .... What Colour TV sold the most?
A long while ago, the above question was posed on our forum. Lots of TV's were suggested, and many felt it would have been the Philips G8. Well, if Telepart are to believed, and I see no reason why they would fabricate this, the answer is the Thorn 3000/3500 series.
I think the Thick Film was more to do with keeping manufacturing costs down, reliability which didn’t occur was a nice marketing statement, or perhaps I am cynical.
I am not surprised with 3000/3500 being favourite but probably rented in much larger numbers than sold. Thorn had possibly the largest rental group in the country.
Telpro, I do vaguely remember them, I may have used them for spares but it’s a very dim memory.
The "Magic circle" was nothing more than an external rectifier diode. We used to do this often with failed mono sets (not just thorns) . The premise being the internal rectifier would fail short, and the resulting AC at the final anode did nothing much to accelerate electrons. another rectifier in series, and it's away again. We used to have a draw of stick rectifiers for just this purpose. I keep meaning to try this on my franken-pye 169 to see if that's what's causing rapid failure of the EHT when it gets slightly warm... a lack of rectifier being the issue !
Yep, the monochrome Lopt mod was done regularly quite why it was named the magic circle I have no idea.