The resistance of the head measured was 650 Ohms and the Impedance 650 mH. The gap measured was 12 mu.

Note: The measurements provided are done on perfect heads or stated otherwise. Remember that the principal effects of poor contact between tape and head in play-back & recording mode shows directly at loss of high frequencies. When this loss of contact is due to the gap worn-out state this will directly affect impedance measurements.
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