User's Manual

CMD Technical Description
Main Features
The Digital Channel Module (CMD) is a synthesized, microprocessor-based, high
performance, RF channel selective repeater with 30 Watt output power capability. It is
available in the VHF, UHF and 800/900MHz bands. It is designed to receive a single RF
channel, filter and amplify the channel signal and retransmit it. The CMD is used for
extending the RF Coverage area of an existing radio site by receiving and re-broadcasting
from host to user (downlink) and from user to host (uplink).
The CMD can be used in On-Channel Repeater (OCR) or Translator mode. In the Translator
mode, the CMD transmits on a frequency which is different from the receive frequency. The
On-Channel Repeater is programmed to receive and transmit on the same frequency.
The CMD operation is programmable locally from an RS-232 port on the front panel. The
CMD operating parameters, such as power output, sensitivity threshold, CTCSS, mode of
operation, frequencies of operation, adjacent channel spacing etc can be configured by the
Customer via simple set-up software as described in this manual. The currently programmed
operating parameters of the CMD determine its personality. The CMD personality is stored
in the EEPROM of the unit.
Additional per channel alarm and monitoring functions are available to indicate any Power,
VSWR, Temperature and Synthesizer lock conditions.
The CMD installation is performed by simply plugging it into a Eurocard format 19” EIA
rackmount card cage.
8A074X06 Rev. Preliminary Page 8 of 15
21/08/2003