39
Installing the Antenna
Description, Specifications, and Installation Manual
NOTE A
: Proper trimming and adjustment is critical to the Voltage Standing Wave
Ratio, known as VSWR. (High reflected power levels decrease forward power. The
life of the radio and transmit capabilities are dependent upon the VSWR being low as
possible).
NOTE B
: If two frequencies are being used, then trim the antenna to the transmit
frequency of the system where the antenna is mounted.
3. Insert the elements into their respective locations through the boom, starting with R1
(the reflective element) in the hole closest to the mounting holes. Then insert Dr, D1
etc. in that order.
NOTE A
: Shortest element is furthest away from the mount and increases in size as
it gets closer to the mount.
NOTE B
: Be very careful to line up the holes and not cross thread when securing
the elements in the next step. The bolts must tighten all the way down upon the lock
washers.
4. Secure the elements with the stainless steel 10-32 hex bolts and #10 lockwashers
provided.
5. Locate the connector/brass tube assembly in the gamma match parts bag and insert
the assembly first through the connector bracket, then thread the connector into the
bracket. Be sure to tighten the connector fully. A drop of Locktite or other thread lock
may be used in the threads to eliminate the possibility of the connector loosening.
6. Slide the gamma link onto the driven element and assemble the gamma match as
shown in figure 1 or 2 (under the antenna instructions provided by the antenna
manufacturer). Set dimensions “A” and “B” to those shown in table 1. Setting the
match to the dimensions shown for your antenna is a good starting point, which
allows you to quickly line tune later. Complete the assembly by attaching the end cap
onto the end of the gamma tube. The antenna is now ready for final tuning.
Antennas may cause severe burns. Do not touch the antenna while the radio is
transmitting.
Final VSWR Tuning
To final tune the antenna, do the following:
1. Before final installation of the antenna, temporarily set it up in a clear area at least six
feet above the ground.
NOTE A
: Do not touch the antenna while the radio is transmitting.
NOTE B
: Ensure antenna is not touching any conductive material and is pointed
away from all objects and people. Pointing antenna at objects in close proximity may
act as a reflector and create inaccurate readings.
