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From Forward to Stop (Tape Moving in Rewind Direction)
It
is possible, while shuttling tape at high speed, to have the tape moving in
the rewind direction but to have the controls in the forward mode.
If
the STOP
button is pressed at this time, K8 pulls in in the ma nner described above. However,
K6 is not released in favor of K7 because S14 is held closed by the sense switch vane
while 513 is open.
Thus, K6 remains operated and the tape comes to standstill
and attempts to reverse, at which time the sense switch opens 514, releasing K4
and putting the mechanism in standby.
At this time the lifter solenoid is released,
and K8 is released by the break at K6 contact 7 and 11.
The Door solenoid remains
operated through 512 unless manually overridden to break S12.
From Forward to Rew ind
Considering the tape to be in the forward mode regardless of its actual
direction, relay K6 is energized.
Pressing tht!
REWIND pushbutton closes
a circuit to operate K7 through K3 contacts 10 and 2,
J6-11,
.S3,
52, J5-R,
K8 contacts 2 and 10 to K7 -14 through K7 -13, CR 19 and R6 to ground.
Relay K7
operates, opening the holding path for K6 at K7 contacts 3 and 11, which releases,
further breaking its holding circuit at K6 contacts 8 and 12.
Torque power to the
reel motors is therefore reversed.
Relay K7 locks up through K8 contacts 10 and
2, and K7 contacts 7 and 11.
From Rewind to Forward
ConSidering the tape to be in the rewind mode regardless of its actual
direction, relay K7 is energized.
Pressing the FORWARD pushbutton closes
a circuit to operate K6 through K3 contacts 10 and 2, J6-11, J2-12, J2-11,
53, S2, 54, J5-S, CR 17, and K8 contacts 1 and 9 to K6 -14.
Because J5-5 applies
bus potential to CR20 a s well as to CR 17, the coil of K7 is effectively shorted, since
the total voltage appears across R6.
This releases K7, K6 remains operated over
the path K7 contacts 11 and 3, K6 contacts 12 and 8, and K8 contacts 1 and 9.
Torque to the reel motors is therefore reversed.
From Rewind to Play
In the rewind mode, regardless of actual direction of tape motion, relayK7 and
K4 is energized.
Pre ssing PLA Y pushbutton S5 causes bus power to flow through
J6-D, J2-9, J2-10, 55, J6-18, and CR4 to operate K3.
A holding path is established
through K7 contacts 12 and 8, K3 contacts 11 and 7, R1, CR8 and CR7 so that K3 will
not release when 55 is released.
Relay K3 contacts 10 and 2 open the paths to 53,
52 and 54 pushbuttons to render them inactive at this time.
The potential from K7
contacts 12 and 8 through K3 contacts 11 and 7, and through R 1 also feeds through
CR9 to terminal 14 of K8 causing it to operate.
Because this action opens the
holding path of K7 through K8 contacts 10 and 2, and K7 contacts 7 and 11, an
unstable condition could arise, but this is prevented by the charge in C12, which
continues to hold K8 until the transfer of K7 is completed if need be.
Whether K7
M64 PAR 2-71
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