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INTEROPERABILITY DOS AND DON’TS
These “universal” rules will help to ensure that the part of communications interoperability will work
properly.
1.
Maintain COMSEC when forming interoperability bridges.
2.
Verify that only one interoperability bridge in the area is using the radio frequencies that you
will be using.
3.
Audio and RF cables should be separated from AC power cables by 12” (use an external DC
source or batteries when you cannot maintain the separation).
4.
When plugging in two or more radios within the same radio band (i.e. VHF) into a radio
bridge, like the ICRI, provide as much vertical separation as possible to reduce the chance for
interference due to the transmitted signal from one radio reducing the receive sensitivity of the
other “in band” radios. Consider using external mobile antennas connected to the radios if
necessary. Use only bridge interconnect cables that are well shielded.
5.
Some bridge cables contain in-line, audio amplifiers for radios designed with low audio levels.
It is best to rout those cables away from radio antennas and connectors---lots of RF and distort
the audio amplifier’s output to the bridge.
6.
Don’t use “SCAN” mode for any radios connected to a radio bridge. This is particularly
important when you are using the bridge as a tactical repeater, where two or more radios have
similar channel programming. If both radios are capable of hearing the same signal, they will
key each other up "ping-pong,” interfering with the function of the bridge.
7.
When using a remote device to control an interoperability bridge, verify configuration of talk
groups with on-scene commander. Do not change talk groups settings without confirmation
from local personnel to avoid inadvertently removing necessary personnel from radio traffic.