lost entirely, or the erase head will either fail to erase, or improperly erase when a recording is made.
The tension idler near the takeup reel serves the same purpose as the other tension idler. The torque on
the takeup reel changes according to the amount of tape on the reel.
Figure 3-31. Tape transport
b. Functions of the tape transport are:
(1) Reproducing. With the recorder/reproducer turned on and the tape properly threaded,
selecting the reproduce mode causes the control circuitry to release the main-reel brakes and starts the
reel motors, the capstan motor, and the capstan idler. As a result, the recorded tape is pulled past the
heads at a constant speed. The signal sensed by the record or reproduce head is equalized and amplified.
(2) Recording. In the record mode, the tape is moved as in the play mode. During recording,
an erase signal from an internal oscillator is fed to the erase head, which clears any previously recorded
signals from the tape before it reaches the record head. Information to be recorded is amplified, mixed
with a bias signal, and applied to the record head. The information is recorded on the tape as it is pulled
past the record head.
(3) Fast Forward/Rewind. With the recorder/reproducer turned on and the tape properly
threaded, selecting the fast forward mode locally or remotely causes the control circuitry to release the
main-reel brakes and apply full power to the takeup reel motor and hold back power to the supply reel
motor. The control circuitry also causes the tape to be lifted away from the heads. Tape is then rapidly
wound onto the takeup reel. The rewind mode is similar to the fast forward mode, except that full power
is applied to the supply reel motor, and the tape is wound rapidly onto the supply reel.
(4) Edit. Three edit modes are selectable at the front panel of the
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