Fostex A-8 - Page 82

sound muddy by effect of the recording signal leakage or cause oscillation at
ping-pong recording whereby the playback output is transferred to another track.
2) Sync crosstalk occurs in relation to the track and pitch dimensions of the head
and its construction, and since this cannot be corrected without affecting its
frequency response, to be aware of how much margin there is before oscillation
occurs at ping-pong recording is very important at drawing out best performance
from the recorder. Sync crosstalk must be measured , of course , when the head is
replaced with a new one.
3) It is in good normal condition if sync crosstalk is lOdB or better, when either
track of two adjacent ones, is put in the record mode.
4) To adjust TRACK 1, for example, load a blank tape on the transport, put TRACK 1
in the sync mode (playback) and TRACK 2 in the record mode.
Plug in a level meter to the TRACK 1 OUTPUT jack, an audio oscillator to the
TRACK 2 INPUT jack and apply a 20Hz 20KHz, -lOdBV (0.3V) signal to the recorder.
Thus, the signal appearing at the TRACK 1 OUTPUT is sync crosstalk.
If crosstalk from TRACK 1 OUTPUT is higher than -lOdBV (0.3V), TRACK 1 cannot be
playbacked for transferring to TRACK 2 as oscillation will occur.
5) As TRACKS 2 through 7 will each have two adjacent tracks, either one side only
is put in the record mode at taking measurements.
It could be useful in using this recorder if, for reference, the figure for
both tracks in the record mode is measured.
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