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Old 4th Mar 2021, 10:15 pm   #203
ajgriff
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Join Date: May 2004
Location: Halifax, West Yorkshire, UK.
Posts: 2,587
Default Re: Commodore PET 2001

Interesting background information and will help me to check the waveform shapes. That's if I ever manage to find any sensible looking signals of course.

Although I think the PET datasette's tape head is ok I thought I'd compare the out of circuit head resistances of the heads in the two machines. The PET's head reads more or less exactly 310Ω whereas the C64's is 195Ω. I appreciate that the operational impedance of the head coils would be a more relevant measurement but it does seem odd that the resistances are so far apart bearing in mind that they both feed identical input circuitry. Is this another red herring?

Alan
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