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UNl
UNl MISCELLANEOUS UNITS
UN1/l
Consists of two magnetic
Transductor MFB.179. Used
Llangollen on P.O. lines.
WITHDRAWN.
amplifiers using Elliott
for lightning protection at
Mounted in CT2/7. DD 1959.
UN1/2
Detector
starting
T1.1.5.
Unit used
signal.
OBSOLESCENT.
on PA1/24 to detect the 1975c/s
CH1/7A.
DD 1959.
DD Spec 2.158.
UN1/3
Unit, Magnetic Amplifier and Power Supplier, used for d.c.
signalling over P.O. lines where lightning protection
precautions have to be taken. Consists of unearthed 40V
power supply switched on by a relay for sending signals to
line, and a magnetic amplifier for telemetering line
current to a remote meter. Mounted in CT2/7. DD 1959.
DD Spec 2.134. TI.L.4. OBSOLESCENT.
UN1/3A
Used with PA6/46 at Meldrum. DD 1961. WITHDRAWN.
UN1/5
Unit, Magnetic Amplifier and Relay used to amplify and
detect d.c. signals on lines subject to lightning strikes.
Provides a voltage barrier of 20kV d.c. between P.O. cable
and station apparatus. Mounted in CT2/7. DD 1959.
DD Spec 2.133. T1.L.4. OBSOLESCENT.
UN1/6
Transistor/Relay Switching Unit used for remote control of
unattended transmitters by small direct currents over
music lines without phantom circuits. Uni-directional
current operated. DD 1959. WITHDRAWN.
UN1/7
Similar to UN1/5 but with two magnetic amplifiers and
relays. DD 1959. DD Spec 2.133. TI.L.4. OBSOLESCENT.
UN1/8
Similar to UNl/6 but uses miniature enclosed relays and is
bi-directional current operated. DD 1959. WITHDRAWN.
UNl/9
Tone Detector Unit used on VF Switching System. Normally
mounted on PN3/18. Transistors: 4 OC203. DD 1960.
DD Spec 2.174. DDHB 2.111. TI.L.2. OBSOLESCENT.
UN1/10
Microphone Distribution Unit giving outputs of 30~, 30~
and high impedance from 30~ microphone input. DD 1960.
OBSOLESCENT.
UN1/11
Microphone Adaptor Unit
DD 1960. OBSOLESCENT.
with various output plugs.
UN1/12
Unit, Amplifier (Magnetic), Power Supplier and Relay used
for lightning protection at Me1drum. Similar to UN1/3 but
with relay section added. DD 1960. OBSOLESCENT.
UNl/13
Unit, Return Loss Bridge used to determine a figure of
merit from terminating impedances in terms of magnitude of
reflected wave. DD 1960. WITHDRAWN.
UN1/14
Unit, Equaliser used on PN3/l9 with PS3/8, UN10/4, GPA/4A.

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