In article , Geoff Mackenzie
wrote:


Wasn't there a turntable in the seventies which dispensed with the
stylus altogether, using instead some sort of optical pickup? Called
the Finial, or something like that. Got reinvented and asked for more
funding every six months or so. IIRC only one escaped and was reviewed
in HFN - worked reasonably well, but was completely defeated by surface
pops which came out at ear-shattering levels.

IIRC a version was finally brought to market and sold (at a high price) to
libraries and archives where they wanted to transcribe historic relics with
zero risk of mechanical damage. I think it did require a combination of
ultra-clean surfaces and for the output to be edited to remove the
remaining clicks, etc.

Along the same lines I do have a book that recounts how some of the early
Baird experimental *video* recordings onto '78s' were recovered by optical
scanning and then reprocessing of the data to recover images. The results
showed that they system did work - provided original users were prepared to
wait decades until methods like the above had been developed for replay.
:-)

Slainte,

Jim

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