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Default Cassette tape speed adjustment


"N_Cook" wrote in message
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Ron wrote in message
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N_Cook wrote:
Ron wrote in message
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N_Cook wrote:
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Set up a sig genny and test him out



Much easier to say the test tape is stretched.
Perhaps perfect pitch testing would only work by playing the likes of JSB
Tocatta and Fugue in D major, not pure tones

How come I cannot google the rpm of an audio cassette capstan? A
calibrated
strobe and tipex mark on the capstan periphery should give a definite
answer
(assuming the spindle is clean and not worn).
It should be determinable from tape speed of 1 7/8 in per sec and spindle
diameter, that is about 1.9mm, but what should it be to 0.1 percent
accuracy?



The rotational speed of a cassette capstan is not a fixed given. The
diameter of capstans vary from machine to machine, and the correct speed of
tape transport is then a function of how fast you drive the capstan round.
The reference in my strobe tape, is indeed the mains. I have been using this
tape for many many years, and I have //never// had anyone complain that the
speed of their machine is off, after I have used it to set one up. Konig
must think that the mains is a good enough reference, otherwise, there would
be no point in them marketing the tape for the purpose of setting up speed.
Exception to this. As Ron said, very occasionally, when an owner has
recorded tapes when the machine was running at the 'wrong' speed ...

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