TENSION SENSOR
The tension sensor, arm and pin, is connected to a potentiometer and pushes against a leaf spring.
This assembly measures the tension of the tape as it runs through the mechanism. The pin that
touches the tape must be perpen-dicular to the transport panel. With the machine in the
diagnostic(display #2) mode, the front panel readout for the tension sensor should be "00" or "01"
when the tension arm is at its rest position. If not, the set screw that connects the arm to the
potentiometer shaft should be loosened and the shaft of the potentiometer changed to achieve the
"01" reading on the display.
The spring should be adjusted so there is a slight pressure against the arm at the rest position and
that there is a force of 45 grams at the middle of the arm's travel when measured at the tape guide pin.
The squareness of the threading arm pin can be most easily adjusted with .010" thick washers on the
three mounting support spacers that mount the tension potentiometer assembly to the panel.
THREADING ARMS
The threading arms are spring loaded so that the arm wheels should be pressing lightly against the
transport panel at all times. It is most desirable that
both wheels on the threading arms be in contact
with the panel. However, this may not be true when the tape is threaded and the tape tension pulls on
the threading arm slightly. It is normal for the rear wheel to lift off the panel slightly and touch the
underside of the threading arm guide plate.
THREADING ARM ROLLERS
The blocks of metal that hold the threading roller should be close to perpendicular to the transport
panel, however, there may be slight variations to this as the roller was adjusted for proper tape travel.
The angle of the threading
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