User's Manual
UCR411A
LECTROSONICS, INC.
20
Pre-coordinated Frequencies
Interference from IM (intermodulation) is a potential 
problem in all multi-channel wireless systems, so proper 
frequency coordination is always required to avoid 
noise, range and dropout problems. Your options to ac-
complish this include: 
 • Usingthepre-coordinatedfrequencygroups 
 • Performingasystemcheckout 
    (See Multi-channel System Checkout) 
 • CallingLectrosonicsforassistance
Groupings of compatible frequencies have been cre-
ated to minimize intermodulation problems in multiple 
channel wireless systems. The frequencies can be used 
with Digital Hybrid and analog Lectrosonics wireless 
equipment. Compatibility with other brands is likely, but 
not guaranteed by Lectrosonics.
Pre-coordinated fre-
quencies within each 
block are arranged in 
four groups (Grp) as 
shown at right.
Example: Block 22
The uppermost eight 
frequencies comprise 
Grp a, the eight just 
below them comprise 
Grp b, and so on.
Grp a and Grp b are 
compatible with one 
another.
Grp c and Grp d are 
compatible with one 
another.
There is no assurance 
that the upper 16 (a,b) 
are compatible with the 
lower 16 (c,d).
BLOCK 22
FREQ SW SET US TV CH
563.700 0,
5t
v29
564.300 0,
Bt
v29
565.200 1,
4t
v29
565.800 1,
At
v29
567.100 2,
7t
v30
568.000 3,
0t
v30
568.500 3,
5t
v30
569.300 3,
Dt
v30
575.700 7,
Dt
v31
577.900 9,
3t
v31
578.600 9,
At
v32
579.900 A,
7t
v32
581.700 B,
9t
v32
582.600 C,
2t
v32
585.200 D,
Ct
v33
587.500 F,
3t
v33
BLOCK 22
FREQ SW SETUS TV CH
570.100 4,
5t
v30
570.700 4,
Bt
v30
571.600 5,
4t
v30
572.200 5,
At
v31
573.200 6,
4t
v31
574.400 7,
0t
v31
574.900 7,
5t
v31
575.500 7,
Bt
v31
581.100 B,
3t
v32
582.100 B,
Dt
v32
582.600 C,
2t
v32
584.300 D,
3t
v32
585.000 D,
At
v32
585.600 E,
0t
v32
586.300 E,
7t
v32
588.100 F,9 tv32
Grp a
Grp b
Grp c
Grp d
NOTE: Pre-coordinated frequencies do not guard 
against interference from outside sources.
When a pre-coordinated group is selected, it is still nec-
essary to check for interference from outside sources. 
Groups a, b, c and d each store 8 frequencies. After 
selecting one of these groups, step through each fre-
quency one at a time and check for interference before 
trying to use the frequency.
To check for interference, set the frequency on the 
receiver, then return to the Main Window and observe 
the RF level indicator with the matching transmitter 
turned OFF.
RF Level Indicator
Even a weak signal, as shown here, will have a sig-
nificant effect on operating range and dropouts. When 
interference is present with the transmitter turned off, a 
warning message will flash on the screen periodically.










