UNl
- 350 -
UNl/144
Current Limiting Unit used in MAl/l to provide a current
foldback limiting interlock circuit. Printed wiring board
for BBC/ISEP system. SCPD 1972. OBSOLESCENT.
UN1/145
OB Monitoring and Output Unit, of commercial design to BBC
specifications, for use in OB mixer equipment. Can be
operated from a.c. mains or batteries, and provides power
for up to two units type UN9/25 and for UN9/26. Desk
mounting box, 62lmm x 460mm x 260mm, with sloping front
for control panels and plug in modular system for
individual units. SCPD 1972. OBSOLESCENT.
UNl/146
OB Monitoring and Output
additional power supply for
mounting box, 5l4mm x
OBSOLESCENT.
Unit, as
condenser
470mm x
UNl/145 but with
microphone. Desk
330mm. SCPD 1972.
UNl/149
Power Supply Changeover Unit for use with pair of power
suppliers to detect failure of main unit and automatically
switch load to standby unit. Also operates when output
from main unit has excessing ripple. ISEP modular printed
circuit board. SCPD 1972. OBSOLESCENT.
UN1/156
UNl/157
DD 1974. CANCELLED.
DD 1974. CANCELLED.
UNl/159
DD 1974. CANCELLED.
UN1/50l
UNl/502
Back Projection Unit. DD 1959/60. WITHDRAWN.
Field Synchroniser used with Ampex Recorders. DD 1959/60.
WITHDRAWN.
UNl/503
Unit, Phasing, 50c/s used on UN3/50l
the 50c/s locking tone. DD 1959/60.
to phase correctly
WITHDRAWN .
UN1/504
Unit, Jumper, Coaxial
OBSOLESCENT.
used
on
PA1/504.
DD 1961.
UNl/505
Unit, Field Pulse Inserter. Used with test apparatus such
as GE4/504 and GE4/505 to provide fully composi,e waveform
for
testing
camera
channels,
video
tape
recording
equipment etc. Case CS2/7A. Mains operated. Valves: 9
E88CC, EL822,
2
M8079,
A2293,
l2AX7,
85A2.
DD 1961.
DD Spec 9.16. DDHB 9.21. ACO. OBSOLESCENT.
UN1/506
Unit, Flywheel Sync. Pulse regenerator used with video
tape recorders to remove "jitter" from leading edge of
sync pulses. Comprises component units A, Band C each on
CH1/12A chassis, with D as alternative to A where remote
control is required of timing or processed sync signal.
Printed wiring and
transistors.
DD 1961.
DD Spec 7.6.
DDHB 7.51. ACO. OBSOLESCENT.
UNl/507
Field Interval Signal Eraser. Used to remove test line
signal from video programme signal. Includes AM4/503,
AM4/504, UN1/508 mounted on PN3/2. PA9/502 is used for

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