- 195 -
MN1
subject to inpu1se noise out of programme hours. DD 1964.
OBSOLESCENT.
MN1/1B
Similar to MN1/1A but
increased forward delay
follows a 1imiter which
of compression in the
WITHDRAWN .
with reduced sensitivity and
time. Used where the monitor
introduces an appreciable degree
programme. CH1/12A. DD 1970.
MN1/2
Switch Operations Monitor used in PA6M/53 to monitor the
line for both correct and incorrect switching operations.
CH1/1SE, pegs 4, 42. DD 1966. WITHDRAWN.
MNl/3
Programme Failure Monitor to give an alarm when incoming
programme drops below a given level for a pre-determined
time. Similar to MN1/1A but without power supply.
CH1/l2A,
pegs
10,
32.
DD 1967.
DD Spec 5.123.
OBSOLESCENT.
MN1/4
Sepmag Sound Synchronisation Monitor for continuous
monitoring of relative speeds of a sepmag machine
transport motor and an associated film camera monitor.
DD 1967/68. WITHDRAWN.
MN1L/5
Programme Carrier Monitor and Alarm (Sending) used to add
a 10kHz tone to programme material on a Programme Carrier
Circuit. Includes OS2/32, UN1/103, FL4/36, AM7/2 for
mounting in half width PN3/23. DD 1967/6S. WITHDRAWN.
MN1L/6
Programme Carrier Monitor and Alarm (Receiving) used to
extract from incoming programme material the 10kHz pilot
sent by MN1L/5 and compare it with a locally generated
10kHz tone. The frequency difference in indicated on a
chart-recorder and an alarm is operated when the drift
exceeds a predetermined limit. Includes MNl/7, UN20/13.
Mounts in half width PN3/23. DD 1967/6S. WITHDRAWN.
MNlM/14
Fault Reporter Monitor. Converts serial fault reporter
data into a numeric display and print out. The input
signal from a fault reporter is obtained from a connection
to the telephone system. The print out on 60mm paper tape
includes the time that the message was received. PN3/54.
DD 1976. CANCELLED.
MNl/50l
Monitor, UHF Transmitter. Used with OT2/501 to monitor
60Mc/s FM signal from TV/FM/lA and 600Mc/s FM signal from
FMP/3 giving video output for display on a picture
monitor. Mains operated. CS/2SA. Valves: A2293, S5A2,
25A/163K,
2
6BW7,
2
6BQ7.
DD 1957.
DD Spec 6.74.
OBSOLESCENT.
MN1/502
Sync Pulse Monitor. Operates an alarm when sync pulses
fall below a certain level. CH1/12. Mains operated.
Electrically similar to UNS/50l. Transistors: OC33, OC40,
3 OC42, 2 CCS3. Suffices A, B indicate 405 and 625 line
versions respectively. DD 1961. DD Spec 5.60. ACO.
OBSOLESCENT.

95