frequency is 27.lkHz.
As for MDl/3, except
DD 1978. DDMI 2.455(81).
76kHz DPSK Modulator. This unit accepts serial data and
clock inputs, and generates a 76kHz differential phase-
shift keyed signal. Two isolated outputs are provided
which, with appropriate series resistors, are suitable for
bridging 75Q or 600Q circuits. CHl/63. DD 1977. DDMI
VHF Stereo Modulator. VHF Stereo Modulator for internal
wired distribution service. Similar to MDl/4, (CH1/12A).
Inputs: High impedance A and B balanced AF
I/P 76 KHz 'Radio Data' I/P.
Outputs: Crystal controlled Band 11 FM carrier
Buffered, coded stereo multiplex.
This unit is intended to be used with Termination Panel
PA20/28. Power requirements mains. CH1/64A. DD 1982.
DDMI 5.425(83). EDI 10474 (1) NOV 83. HB 5.163(83).
V.H.F. Sound and Vision Modulator. The unit accepts video
and sound at standard level and produces a modulated V.H.F
crystal controlled signal (vestigial side band) suitable
for conversion to any television channel for feeding
commercial colour and monochrome television receivers.
frequency = 32.9 MHz. Power requirements mains. CH1/64A.
Parent equipment MD1/5l0A. DD 1980
RDS Modulator. This unit accepts a standard RDS bit-stream
and converts this into a 57 kHz modulated carrier in
accordance with EBU Spec.No.3244-E. Power requirements 5 V,
Termination panel PA20/37.
BBC chassis CH1/86.
Parent equipment CD4L/2l. Sub-units MD2/2, DM2/5.
D & E D(A) 1986.
Line Driver and Modulator. This card accepts as its input
serial data from the CD2/520 Serial data coder and provides
a balanced output together with a modulated output suitable
to transmit the data in the reverse direction to a video
signal. The card also accepts 6 bit BCD coded data and
provides 25 outputs to drive LED's to indicate the number
represented by the data. This card together with the
CD2/520 Serial data coder and UN23/655 control panel
interface form the CD2L/5l6 Matrix remote control coder.
Power requirements +5V. 3U standard ISEP. DD 1977. DDMI
Line Driver and Modulator. This card is the same as the
MD2/5ll but has additional circuitry to provide 39 instead
of 25 output drives for LED's to indicate the channel
number represented by the 6-bit BCD data. Power
requirements +5V at 250mA approx, -5V at 70mA approx. 3U
ISEP. Parent equipment CD2L/5l6. DD 1980.
Frequency Modulator used in TM3M/8. Output frequency in
l05MHz deviated by up to 50kHz. Audio bandwidth is 17kHz.
Printed circuit board 250mm x l45mm. Mounted within
framework of TM3M/8. DD 1976.