~8
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studio communication systems. Speech only. Maximum
output is 1 watt for input level of -28dB. Z in: high.
114mm x 57mm x 102mm. DD 1964. DD Spec 3.396. ACO.
OBSOLETE.
~8/9
Used with Goodmans 'Maxim' loudspeaker at OB points.
Maximum output: lOW into 15~ with input level of -12dB at
1kHz. Boost of 8dB at 50Hz. Mains operated with
provision for supply from external 45V battery. Case
l2lmm x 190mm x 83mm is bolted to loudspeaker cabinet.
DD 1964. DD Spec 3.419. ACO. OBSOLESCENT.
~8/9A
Version of AM8/9 with protective covers over transistors
mounted on the outside of the box and mounting detail to
permit installation in miscellaneous situations without
the necessity to disturb internal assembly. DD 1968.
DD Spec 3.419. OBSOLESCENT.
~8/10
Used in LS1/4 with l2V battery consisting of
Imput
impedance
20k~.
Printed
board.
OBSOLESCENT.
U2 cells.
SCPD 1967.
AM9 MICROPHONE AMPLIFIERS
~9/1
Transistor Amplifier used
DD Spec 3.172. OBSOLESCENT.
in
UN3/50l.
DD 1958.
~9/2
Transistor Amplifier used in mobile
DD 1958. DD Spec 3.210. WITHDRAWN.
control rooms.
AM9/3
Portable Transistor Amplifier used for intercommunication
by camera crews on OB's in an aircraft. DD 1960.
WITHDRAWN.
AM9/4
Portable
steps.
supply.
600~.
ACO.
Transistor Amplifier with gain
Operated by internal battery or
Source resistance 30~ or 300~.
127mm x 92mm x 92mm. DD 1960.
OBSOLESCENT.
of 45dB in 10dB
external power
Load resistance
DD Spec 3.309.
AM9/6
Consists of two amplifiers electrically similar to ~9/5
but both
mounted
in
CHl/18C.
Gain
controls
on front
panel. DD 1963. DD Spec 3.363. ACO. OBSOLESCENT.
~9/6A
Similar to ~9/6 but for externally mounted gain controls.
DD 1963. DD Spec 3.363. OBSOLETE.
~9/7
Response Selection Microphone Amplifier. Works directly
from a 300~ microphone into Type A or B studio equipment.
Has similar controls to AM1/4. Gain: 50dB. CH1/l8Ct pegs
5t 30. DD 1966. DD Spec 3.428. ACO. OBSOLESCENT.
AM9/8
Used in sound control modules in Type D studio equipment.

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