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Re: An interesting Apple II cassette ditty



On Sat, 16 Jan 2010, schmidtd wrote:

On Jan 16, 11:37 am, "Jayson Smith"
     On an unrelated topic, does the long header tone actually serve any
purpose to the Apple during a read? How much tone does it actually need when
reading the tape?

It serves to synchronize the bit stream.  You need something like 2-3
seconds to latch on to the signal.

Also, a longer header of steady tone makes it much easier to find the start of a program if you have a recorder that can provide playback while fastforwarding and rewinding. It's much easier to hear a long tone as something distinctive when doing that than a shorter tone that might be
something else.  A longer tone ensures it can't be confused with anything.

   Michael