Cassette Speed Adjustment Test Tape

Use a good quality pre recorded tape?

N

Hi...

Must be that I'm missing something here... how is an alignment tape used to check speed?

Think I'd prefer a tape recorded on a known good (speed) machine with a nice say 5k tone on it; then look at it on the suspect machine with a freq counter?

Or the quick and easy way... take a commercial tape, with song lengths printed on the label... choose the longest song on it... play it; timing it with a stop watch and see how close it comes :)

Take care.

Ken

Ken

I'm sure he must have been referring to a head azimuth alignment tape -- which would have at least one steady tone on it. ASTI Magnetics offers (or at least used to offer) the more costly, single-purpose variety. Or he could get one of the popular all-in-one tapes for $20:

Checking the play speed of a cassette recorder. Requirements: a 1KHz test tape or a recording of an accurate

1KHz tone made on a known good tape unit and played back on that machine to check, and an audio signal generator with a fully floating output ie no dc reference if not then de-couple the output with a couple of capacitors.Parallel together one channel of the phones output of the tape and the output of the sig.gen. and a set of headphones in mono (L and R connected).With approximately equal sound levels you should get unmistakeable beat note .Reduce the beat to a minimum by changing the speed regulation of the cassette unit motor.

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No, not necessarily. There are tapes made specifically for determining the speed of a cassette machine. They are typically 3.150 kHz. Play the tape, measure the frequency of the tone with a frequency counter, and adjust the speed accordingly. A commercial version is available at

but quite a few other companies used to make them. I just cannot find one of those companies, although the source suggested above may be a good one. The descriptions on the tape do not tell what other tones are available, but I assume that the speed test would be one of them. Thank for the pointer.

This is certainly a viable technique, but it is not as accurate as a test tape with a frequency counter. Thanks for reminding me!

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Or get a friendly musician to listen to it and tell you if the pitches are high or low.

N

This method works very well IF you can find a known good tape deck. When I used to work on a lot of tape decks, I don't think I ever saw two that were even close to the same speed (usually they were too fast). Many were off enough so that it was obvious when listening to music. Even the two sides of double decks were rarely both the same speed. Expensive decks also varied a lot. Andy Cuffe

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Somewhere I have / had a cleaning tape with a built in strobe disc. Try dollar stores?

N

Hi Ken,

Problem is the running times printed on those labels are often highly inaccurate :)

John

the

headphones

f counter is a bit OTT, I've never come across a cassette tape player that is consistently within 1 c/s of beats at 1 KHz of test tape. Perhaps something with huge motors and flywheels but not ordinary domestic kit.

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