Bird Technologies 81-37-25 Series User Manual
Page 6
TX RX Systems Inc. Manual 7-9095-3 01/17/06 Page 2
value of the loads installed. See the specification
charts at the end of this manual.
VHF models maintain their specifications over a
2.5% bandwidth which equals 3.8 MHz at 150
MHz. UHF models have a minimum bandwidth of
1.25% which equals 5.75 MHz at 460 MHz. When
the frequency of operation needs to be changed
by more than about half of the above mentioned
bandwidth figures, tuning of the isolator will ensure
optimum performance.
INSTALLATION
All isolator models may be mounted on most sur-
faces but should not be located where they will be
exposed to moisture or very high humidity. TX RX
Systems' isolators are well shielded magnetically
and may be mounted on steel cabinets or panels.
A mounting hole layout is shown in Figure 2.
The isolator loads can get quite
hot during operation. This can
occur when an antenna system
component fails causing high
reflected power which is then dis-
s i p a t e d by t h e i s o l a t o r l o a d .
These loads can get hot enough
to burn skin so use caution when
servicing these devices.
Recommended Test Equipment for Tuning
The following equipment or its equivalent is rec-
ommended:
1.438"
37 mm
3.250"
83 mm
4.688"
120 mm
0.313"
8 mm
5.500"
140 mm
5.813"
148 mm
0.188"
5 mm
3.125"
79 mm
3.313"
84 mm
0.219" (6 mm) Dia
Mounting Holes
4 places
Figure 2: Mounting hole layout.