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UN20
UN20/544
LF Amplitude Detector Unit.
the slope of the 10~s bar
DD 1972. DDMI2.423(76).
used in EQ12M/503 to measure
in the ITS waveform. CHl/63.
OBSOLESCENT.
UN20/545A.B
Shot Change Detector Unit. used with pre-programming
equipment and 'TARIF' to identify the start of each shot
in a film and to send a half second negative going TTL
pulse to the programme when each occurs. Suffix 'A': for
use with Cintel Telecine channel. accepts logarithimic
signals. Suffix 'B': for general use. accepts composite
video signal and mixed synchronising pulses. CHl/12A.
Superseded by RP3L/508. RD 1972. OBSOLESCENT.
UN20 Sub Group not available for new designs. DD 1977.
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UN2l RELAY UNITS
UN21/1
Relay Unit used at Wrotham with NEl/6 to change
transmitter from monophonic to stereophonic transmission
by remote control from London. CHl/18C. pegs 8. 38.
DD 1966/67. WITHDRAWN.
UN21/2
Relay Unit operated by remotely sent d.c. signals to
change programme routing or transmitter input. CHl/18E.
DD 1966/67. WITHDRAWN.
UN21/3
Used at Newcastle and controlled by UNl/9l at Stagshaw.
Sends d.c. signals to Pontop Pike to transfer Home and
Third transmitters from normal programme feed to reserve
feed. CHl/18E. DD 1966/67. WITHDRAWN.
UN21/4
Translator Change-over Relay Unit (100W/10W)
BA13/12 in Mark 11 change-over application.
DD 1966/67. WITHDRAWN.
used on
CH1/12B.
UN21/5A-T
Reed Relay Units for matrix systems using multiple contact
relays (13. 6 or
3
reeds).
Constructed in matrix form.
with vero boards providing the multiples. for monitoring
in CHl/50A-C. SCPD 1968. OBSOLESCENT.
UN21/6
Sound Relay Unit for EP6/501 News Te1ecine Machines in
Television Centre Spur. Mounted on adjacent sound LT bay.
CHl/44. DD 1968/69. WITHDRAWN.
UN21/7
Sound Monitoring Relay Unit for Television Centre News
Te1ecine machines. Mounted on sound LT bay. CH1/44.
DD 1968/69. WITHDRAWN.
UN21/8
TAR IF Relay Unit
Machines. Mounted
WITHDRAWN .
for Television Centre News Telecine
on sound LT bay. CH1/44. DD 1968/69.
UN21/9
Miscellaneous
Relay
Unit for remote facilities for

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