LM Series
Mobile Antennas
The Larsen mount, the industry standard 5/16”-24 THDS stud mount uses a
permanent 3/4” hole.
Pre-Installation Tips
• Resonance may be obtained with the use of a single ground element as small
as 19” long and 1/2” wide. To improve performance, make the ground
plane larger.
• For the best performance, mount antenna on vehicle roof top. The mobile
antenna may also be mounted on the rear fender or trunk lid.
• See cutting chart to cut whip the correct length for operating frequency.
To Attach Mount to Vehicle:
Soldered Connection
1. Trim coax braid. Twist center conductor. Apply solder flux on braid and center
conductor. Tin center conductor.
2. Place coax (braid) in lug channel, press down and solder, making sure there is
enough solder flow for connection.
3. Remove soldering iron and allow assembly to cool.
4. Bend center conductor 90° into the center hole, apply flux and solder
connections.
5. Wipe clean and test for continuity and shorts.
Shrink Tubing Connection
1. Slip heat shrinkable tubing over coax cable. (Fig. 1)
2. Insert cable into soldering hole using a twisting motion for maximum
penetration. (Fig. 2)
3. Attach center conductor to center stud and solder. (Fig. 3)
4. Push heat shrinkable tubing over hole end and as far forward as possible.
Rotate assembly for even heat distribution while heating If tubing does not
shrink evenly into place, continue process. Final assembly should look like
Figure 4.
Mounting Instructions
1. Use hole saw to drill 3/4” (19mm) hole in vehicle.
2. Metal to metal contact between the vehicle and mount is essential for best
performance. Remove any burrs on the under side of the hole.
3. Route coax lead to equipment and slip mount through hole as shown. (Fig. 5)
4. Insert small end of allen wrench into hole on side of insulator nut and use to
tighten into place. On final turn, make sure “O” ring gasket is in place and
LM Series
Mobile Antennas
PI00039, Rev. F, 12/10, 5190.4030
that the insulator nut is centered in mounting hole. Reverse wrench with long
end in hole for final tightening. (Fig. 6)
5. To attach antenna to mount, place supplied rubber washer over antenna
mount. Screw loading coil base firmly against rubber washer.
Fig. 5
Insulator Nut
Car roof O-Ring
Fig. 6
O-Ring
Car roof
Fig. 1
3/8” 3/8” 1/4”
Coax Braid
1”
Center
conductor
insulation
Coax sheath
Shrink tubing
Fig. 2
Fig. 4
Fig. 3
Pulse warrants to every user of a Larsen
product that it will perform to its specified
ratings and will be free of defects in materials
and workmanship.
Pulse will repair or replace without charge
any Larsen product which fails to meet this
warranty within one year of the purchase
date. Excluded is failure due to misuse such as striking objects,
improper installation, and use beyond specifications.
Pulse will not be responsible for any incidental or consequential
damages due to failure of a Larsen product under this warranty or
any implied warranty.
Larsen
®
, Kulrod
®
and Kulduckie
®
are registered trademarks of Pulse Engineering, Inc.
Kulglass
®
Series U.S. Patent #4,764,773; KGB Series U.S. Patent #5,099,252; #5,155,494 - 11/99
LArSen - A Pulse Brand
3611 N.E. 112th Avenue
Vancouver, Washington 98682
Phone: 800-268-3662
360-944-7551
Fax: 360-944-7556
www.larsen-antennas.com
PI00039,
Rev.
G.
04/19,
5190.4030
