COMTEK PR-75a - Manual (Page 9)

Page 7
Multiple Channel Operation
When multiple transmitters (more than two) are used in the same proximity,
intermodulation interference can occur. This condition is common to all
radio receivers to some extent when multiple transmitters are used in the
same operating area. The RF signals will “MIX” together generating
additional signals. If these product frequencies are too close to a frequency
which the receiver can also respond to, you will experience intermodulation
interference which may cause undesirable operation.
To avoid this type of interference when multiple transmitters are used in the
same proximity, transmitting frequencies must be coordinated by selecting
from frequencies in the same group. (See group frequency chart on page 6.)
When programming new customized frequency groups with the FP-75
channel programmer, COMTEK’s Frequency Selection Guide Software can
be used to determine appropriate frequencies. Contact COMTEK to obtain a
free copy of the frequency selection software or download it from COMTEK’s
web site at www.comtek.com/software.html
transmitters transmitters
transmitters
Group 1
operating area
Group 2
operating area
Group 3
operating area
Transmitter
separation
Transmitter
separation
Transmitter Proximities
For Multiple Channel
Operation
Frequency groups being transmitted
should be separated by 2X
the operating area; and for
best performance, the
group operating areas
should have a 100 ft.
minimum separation.