E&M Signaling
The Leased Line interface is equipped with Type IV E&M signaling. If the M lead is
grounded on one end of the link, the E lead will go to ground on the other end of the link.
The E lead can be used to activate push-to-talk circuits or change frequencies on 2-way
radios, turn on lights or alarms, or activate functions on remote equipment. Each leased
line carries one E&M circuit. The E lead floats at +5VDC and the driving circuit must
sink 3 mA. The M lead can sink 75 mA at +/- 60V.
2.3.5 Repeater Operation
The repeater is used to work around obstructions or to extend the range of the
Trailblazer. It consists of two radio cards (a master and a slave) connected digitally.
More than one repeater may be used if necessary.
Trailblazer
Base
Trailblazer
CPE
Trailblazer
Repeater
The repeater slave radio links with the base radio of the system and the master radio
links with the CPE.
Top
Card
Bottom
Card
Figure 8: Repeater Operation
Trailblazer Installation and User Manual
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