AT&T Bell System Plant Series Adjustment Procedure page 9

check tape loop oscillations in the supply reel vacuum
chamber.
2.09
Photosense Head: The photosense head
shall sense the beginning-of-tape (BOT)
marker and the end-of-tape (EOT) marker. The
dimensions and location of the photoreflective tape
markers are shown in Fig. 7. Check requirement
as follows.
(1)
Apply power to the recorder and, observing
the caution in 1.04, install a reel of magnetic
tape with BOT and EOT photoreflective markers.
(2)
Using manual controls, operate the transport
for forward tape movement and run the
tape through completely without interruption.
The EOT lamp on the manual control panel lights
when the EOT marker is sensed by the photosense
head. Stop the recorder when the EOT marker
passes the photosense head.
(3)
Operate the recorder in the rewind mode
and allow the tape to run in rewind toward
the BOT marker. Tape rewind shall overshoot
the BOT marker, decelerate, and stop; tape shall
immediately move in the forward direction and
continue to move until the BOT marker reaches
the photosense head and tape motion stops.
ISS 1, SECTION 034-368-701
3. PROCEDURES
3.01
List of Tools, Gauges, Test Apparatus,
and Materials
CODE OR
SPEC NO.
TOOLS
486A
KS-6854
R-2670
R-2671
R-2958
R-2959
R-3415
GAUGES
79B
Oil Can
Screwdriver
DESCRIPTION
3/32-Inch Allen Wrench
1/8-Inch Allen Wrench
5/64-Inch Allen Wrench
1/16-Inch Allen Wrench
7 /16-Inch Allen Wrench
5-Inch E Screwdriver
Vacuum Cleaner Equipped with
a
KS-14377 L30 Flexible Nozzle (or
equivalent)
0-1000 Gram Tension Gauge
BEGINNING OF TAPE
AND END OF TAPE
RECORDING AREA
I
PHOTOREFLECTIVE MARKERS
~
0.498
+
0.002
1.
~=j,
es<
~rT-+:,L~,l -~:
HUB END~
11!
REFERENCE
EDGE
----- 25 FT
+
5 FT - 0 FT 15 FT
±
I FT
MAGNETIC SIDE
7
Fig. 7-Photoreflective Tape Marker Placement (USASI Standard)
RIM END
Page 9