OSl
OSl/l
OSl/3
OSl/4
OSl/50lA,501B
081/502
OSl/502A
OSl/502C
OSl/504
081/505
051/506
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OSl MISCELLANEOUS OSCILLATORS
Tone Sequential Test Oscillator. Provides test tones at
60Hz, 900Hz, 5kHz, 10kHz, automatically switched at
regular intervals, and also constant 900Hz tone. Output:
OdB accurate. Z out: <7~. Comprises PN3/23 with OS2/l3,
OS2/l4, OS2/l5, AMl/5, UN1/2l, PS2/9. DD 1964.
DD Spec 3.386. ACO. OBSOLESCENT.
Two Tone Code Oscillator. Generates an audio
tone signal for transmission over a telephone
Frequency is controlled by input from MN5/l.
board. DD 1967. WITHDRAWN.
frequency
circuit.
Printed
Two Tone Oscillator, 2700Hz, 2888Hz, used in PA18M/15 to
switch programme via PA18M/14 at Caversham. Includes 2
OS2/26. CHI/18E, pegs 35, 38. DD 1969. WITHDRAWN.
Pulsed Oscillator. Part of C06/50l. Provides train of
pulses for timing operation of high speed switches and
reset pulses for drive pulse units and start pulse unit.
Suffix A indicates llMc/s timing pulses from input of 625
line syncs, and suffix B indicates 7Mc/s pulses from input
of 405 line syncs. CHl/12A. Transistors: 11 ASZ2l, 4
Clll, 3 2N2894. Superseded by OSl/507A, OSl/507B.
DD 1963/64. DD Spec 7.23. OBSOLESCENT.
Burst Locked Oscillator fed from UN1/540 to reproduce a
continuous sub carrier of constant amplitude in phase with
the burst or continuous subcarrier applied to the UNl/540
and maintain it with reduced accuracy without an input
signal. Includes a crystal and oven. Crystal frequency
4.4336l87Mc/s for 625 line PAL. Used in EPlL/508.
CHl/12A, pegs 9, 25. DD 1964. ACO. OBSOLETE.
As OSl/502 but with crystal frequency of
525 line NTSC system. DD 1966.
DDHB 8,190, 8.214. OBSOLESCENT.
3.579545Mc/s for
DD Spec 8.185.
Modified OSl/502 with decreased pull-in range for deriving
a jitter free output from a PAL swinging burst input.
CHl/12A. DD 1966. OBSOLESCENT.
Controlled Frequency Oscillator
Operates at one sixth of sound
CHl/12A. DD 1965. WITHDRAWN.
used in
carrier
OS5M/50l.
frequency.
Frequency Modulated Oscillator, 6MHz, used in EP14M/50l to
provide sound modulation facilities. Includes 3 separate
oscillator circuits: (a) 6MHz for frequency modulation by
an external source or internal 400Hz oscillator, (b)
crystal controlled oscillator, 6MHz, for checking
unmodulated frequency, (c) 400Hz oscillator for internal
modulation.
CHl/39A.
DD 1965.
DD Spec 6.160.
OBSOLESCENT.
Line Flywheel Oscillator producing twice line
pulses for use in Ampex recorders. CH1/l2A.
frequency
DD 1966.

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