9
Functional Description
The 9245DT transmitter accepts a composite video signal in NTSC or PAL format via the BNC video input port. This
baseband video signal is sampled at a 16 MHz rate by an A-to-D converter operating with nine bits of precision.
Data signals are combined into the bit stream and converted to an optical signal for transmission over the optical
fiber. For the reverse direction, data comes into the transmitter via an optical receiver operating at a different
wavelength than the transmitter. The received data stream is demultiplexed into data for output via the data port
and the Option Module Ports.
The receiver accepts the optical signal and converts it back to a serial bit stream. The signal is deserialized and
converted back into the video and data signals, which are output on the BNC and data connectors. For the
reverse direction, outputs from the data port and the Option Module Ports are multiplexed together, converted
to an optical signal for transmission to the transmitter on the second wavelength.
The built-in data port is dipswitch-programmable. The port may be configured for Manchester-encoded data,
RS485-2-wire, RS485 4-wire, RS422, or RS232. The data port supports data at speeds up to 115.2 kbps.
The 9245DT and 9245DR support two TKH Security USA Data/Audio Option Modules. The modules operate
bidirectionally. The user may select from duplex audio (Option Module type A), duplex data (Option Module type
B), duplex contact closure (Option Module type C) or Stereo Audio (Option Module type D, Stereo Input, and E,
Stereo Output).
The Xs in the 9245DT(XX)-Y-ZZ and 9245DR(XX)-Y-ZZ model numbers should be replaced with the letter for the
type of Option Module desired. The specific Option Modules installed are indicated by labels on the front panel
and on the AUX I/O connectors.
The 9245DT and 9245DR are optically compatible with the 9241DT and 9241DR rack-mount card models.
The 9245D module has been evaluated with TKH Security USA external power adapter Model 9014 with input at
110 VAC, 60 Hz, and with TKH Security USA external power adapter Model 9011 with input between 100 and 240
VAC, 50 to 60 Hz. These power adapters are suitable for use at a temperature above 0° C, up to 40° C. The TKH
Security USA PSR adapter may be used between –10° C and +60° C. If the module is to be used in an ambient
outside this ambient temperature range, a power source must be used that is suitable for use at that ambient and
additional evaluation of the module may be required in the end product.
