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identical circuits in same unit, for stereo use.
25 way ISEP connector, indexing positions 7,
DD 1972. DDMI 1.102. DDHB 1.104. OBSOLESCENT.
Headphone Monitoring Amplifier, accepting stereo pair of
input signals and combining them to give mono output
signals for headphones and VU meter. Printed circuit
board, l63mm x 109mm with 25 way ISEP connector. DD 1972.
Used on radio link circuits for viewing on a picture
monitor. Gain: 46dB. Output IV peak-to-peak in 75~.
Printed board. Mains operated. Assembled in copper box
with coaxial connectors. Transistors: 4 OC171, 2 G103.
DD 1961. DDTM 8.65. OBSOLESCENT.
As AMlO/50l but assembled on CHl/12A and converts from
balanced signal to unbalanced DD 1962. DDTM 8.65.
AMll O.B. AMPLIFIERS
Transistor Amplifier functionally the equivalent of OBA/9.
Self contained battery. Transistors: GETl06, 7 GET104, 2
GETl05, 2 GETl13. DD 1957. WITHDRAWN.
OB Public Address Amplifier, 25 watts. Commercial
amplifier manufactured by C.T.H. Electronics Ltd., and
modified to BBC requirements. DD 1968. OBSOLESCENT.
OB Channel Amplifier, of commercial design to BBC
specification. Facilities provided: coarse and fine gain;
phase reversal; response selection; se1ectab1e presence
and loss frequencies; LF filter. Intended for use with
UN9/2S. Wedge shaped modular construction, 45mm wide with
sloping front control panel. SCPD 1972. OBSOLESCENT.
AM11 Sub Group not available for new designs DD 1977
AM12 PHOTOELECTRIC AMPLIFIERS
Photo-electric Amplifier used to
of ,tapes in special cassettes
detect start and
used in RP4/2.
Photo-electric Amplifier used in RP4/4 to detect start and
finish of reproducing tape. Similar to and superseding
AM12/1. PCB. DD 1965. DD Spec 1.59. OBSOLESCENT.