IBM 727 Manual Of Instruction page 123

5AU (76.09.01)
5AL (76.09.02)
5BU (76.09.09)
R6, Flapper switch
relay (76.09.06)
6AU (76.09.01)
6AL (76.09.02)
6BU (76.09.09)
R7, Photo light relay
(76.09.03)
7AL (76.09.01)
7BL (76.09.05)
R8, Tim e-delay motor
relay (76.09.08)
8AU (76.10.02)
8BU (76.09.09)
R9, Load-rewind 2
(76.09.05)
9-1 (76.09.01)
9-2 (76.09.08)
9-3 (76.09.02)
9-4 (76.09.04)
9-5 (76.09.08)
9-6 (76.09.07)
R10, Unload 2
(76.04.04)
10-3 (76.09.09)
10-4 (76.09.09)
10-5 (76.09.03)
Drops relay 1 (run) if tape is not in the left column during
normal operation.
Drops R27 (GO status) if tape is not in left column during
normal operation.
Interlock on pick of R23 (high-speed rewind status).
must be out of left column before entering high-speed rewind.
Picks when the right flapper-valve switch is operated.
Drops relay 1 (run) if tape is not in the right column during
normal operation.
Drops R27 (GO status) if tape is not in the right column dur­
ing a normal operation.
Interlock on pick of R23 (high-speed rewind status).
must be out of right column before entering high-speed r e ­
wind status.
Picked through the tape break, load point, TI lamps when
+48 volts is up. Drops as a result of a failure of any of the
lamp filaments.
Drops R l, HD1, 2 and 3 with a photo light failure.
Interlocks picking R21 (rewind PU) when a photo light has
failed.
Picks during rewind operations to start the time delay motor.
Completes a circuit from phase 1 through the timer motor
to phase 2.
Interlocks picking R23 (high-speed rewind) while timer is
running and drops R23 when timer starts.
Picks at any time R3 is picked.
Parallels R5AU and R6AU to pick R l, HD1, 2, and 3 during
a load-rewind operation.
Allows R13 to be picked before bellows switch operates.
Completes a circuit to manual reverse and R27 during re ­
wind operations Q
Hold circuit for R3 during load-rewind operations.
Picks R12 (rewind status) during load-rewind operations.
Drops nnot file protect" to 76.02.
have write status during a load-rewind operation.
Picked when the tape drive is in an unload status.
Causes the tape break lamp to come on when unload is
depressed.
Causes R16 to be latch picked when the tape is out of the
columns on unload.
Drops the parallel resistance circuit around the R7 coil
causing the photo cell lamps to dim when the drive is un­
loaded.
123
Tape
Tape
Makes it impossible to