IBM 727 Manual Of Instruction page 86

( . )
31-3 09 01
31-4 (09.01)
31-6 (09.02)
R4, clutch (09. 04)
4AL, BL (10.01)
R 5,6, start slow r e ­
wind; HD7, time delay
(09.04)
5AU (09.05)
5AL (09.06)
5BL (09.05)
6AU (09.06) N/C
N/O
6AL (09.06)
6BU (09.02)
6BL (09.05) N/C
N/O
R7, Capstans in (09.05)
7AU (09.05) N/C
N/O
7AL (09.04)
7BU (09.03)
7BL (09.05)
This is for added protection to insure that the tape is file
protected when rewind is initiated, before R35 is picked.
Pick the rewind status relays.
During load rewind, until the capstans are extended, the
R6, 8, 9 and 10 pts. have control of the manual start line.
It is picked while load rewinding until the capstans are ex­
tended, or while unloading. R4 is picked whenever tape is
being lowered into or taken out of columns.
When the stop clutches are energized, it is with half power.
They are picked while rewinding when, or if, the reel arm
switch is closed, or when the reset key is pressed while r e ­
winding in the high-speed area.
stans are extended.
At the start of load-rewind from a loaded status, R5AU de­
termines whether to raise the head cover.
Hold R5, 6, HD7.
Drop R12 and DP3 when the reel arm switch closes during
high-speed rewind. This starts slowing tape down.
It allows the capstans to be retracted when starting a high­
speed rewind or unload operation.
Energize HD8 in preparation to letting capstans out during
the load rewind from an unloaded status, or during loading
portion of a high-speed rewind.
Energize the solenoid magnet latch in preparation to extend­
ing the capstans.
It allows a manual start when unloaded.
condition when the R9BL andRIOBLpts. do not indicate the
true status of the columns.
Allow the take-up motor (HD6) to run while unloading and
while raising the head cover during high-speed rewind.
When open, the timer point has control of the take-up motor.
Reverse the take-up motor field.
It is picked when the capstans are fully retracted.
This allows HD8 to be picked to retract the capstans start­
ing a high-speed rewind operation. When the capstans are
retracted, this point opens the circuit to HD8.
This prevents a manual start while unloading until the cap­
stans are retracted. They prevent running the take-up
motor (HD6) until the capstans are retracted.
This point insures that 1/2 brake cannot be placed on the
reels until the capstans are in.
load button is pressed while the unit is rewinding at slow
speed.
It prevents the end of file reflective spot from being recog­
nized as a tape break.
If the tape should go into either column when coasting to a
stop following a high-speed rewind, R7BL allows the take-
up motor to start without waiting for the time delay pt. to
close.
86
They hold until both cap­
This is the only
This is essential if the un­