UN9
UN9/518A
UN9/519
UN9/52l
UN9/52lA
UN9/522
UN9/523
UN9/524
UN9/525
UN9/526
UN9/528
UN9/529
UN9/530
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connections. DD 1963. DD Spec 7.34, 7.35. OBSOLESCENT.
Output High Speed Switch used on
with 1 UNl/559 on PAl/514A.
OBSOLESCENT.
C06/503.
DD 1965.
36 are used
DD Spec 7.73.
Video Switch Unit. Provides inlay timing switching
circuits of EP5/502 either direct of via a self-contained
equaliser similar to EQ5/5l0 and external delay cable.
Mounts on 64mm of PN3/23. DD 1963. DD Spec 8.142. ACO.
OBSOLESCENT.
Video Switch Unit. Part of PA18/507. CHl/12A. DD 1963.
DD Spec 8.167. ACO. OBSOLESCENT.
As UN9/52l but with improved crosstalk performance.
DD 1970. DD Spec 8.167. OBSOLESCENT.
Operates on trailing (positive) edge of input sync pulses.
Printed board. DD 1963. DD Spec 7.40. DDTM 7.75.
OBSOLESCENT.
UHF Converter Switching Unit used in RC4/502. CH3/lA.
DD 1963. WITHDRAWN.
Used in EP5/502. CHl/12A with relays for group
changeover and application of test signal to mixer
distribution amplifiers. DD 1963. DD Spec 8.181.
OBSOLESCENT.
mixer
output
ACO.
Local Control
control of the
DD 1963. ACO.
Switch used in GEl/5l7 to provide local
dividing factor of the C02/506. CHl/12A.
WITHDRAWN.
Switch Unit (High Speed). First used on UNl/525. Printed
board. Operates from nominal 2V sync waveform and closes
output for adjustable 1.5~sec to 2.2~sec. DD 1964.
DD Spec 7.37. DDHB 7.72. ACO. OBSOLESCENT.
Binary Switch Unit. General purpose 2 input bistable
circuit used as a toggle switch or as a binary counter up
to a clock pulse rate of 10MHz. Printed boar. APl/506
enables 2 to be mounted in one sixth of board area
available in a CHl/l2A. DD 1964. DD Spec 10.3. ACO.
OBSOLESCENT.
RF Changeover Switch (Band I) used in EP7/503 to switch
either of two television translators to aerial and the
other to a dummy load without contacts in the RF circuit.
Constructed in 4 copper boxes with a motor all mounted on
a
l78mm
x
l78mm Tufnor panel.
First
used
PA18M/5l0.
DD 1965. DD Spec 12.27. OBSOLESCENT.
Main Switch Unit, relay controlled, used on BA13/506 and
BA13/507 to turn the main translator on and off under
automatic changeover conditions. Contained in PSlM/13.
CHl/12A. Controlled by MN2/504 via PA6/45. DD 1965.
DD Spec 12.3. OBSOLESCENT.

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