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 WITHDRAWN.
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 WITHDRAWN.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 Superseded by OSl/507A, OSl/507B.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.
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 WITHDRAWN.
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
DD Spec 6.160.
Line Flywheel Oscillator producing twice line
pulses for use in Ampex recorders. CH1/l2A.