10. Before installing the Baluns and Matching / Phasing Harness, thread 3/8” SEAL NUTS fully onto all
connectors, with the black Neoprene face of the nuts facing out. Attach Baluns and Phasing lines to the
Driven Element Blocks and Junction Block as shown on the picture below. Tighten the connectors
gently
using a
7/16" end wrench. Once the connectors are tight, back the Seal Nuts out and finger-tighten firmly up
against the face of the connectors (or tighten
gently
with 1/2” end wrench). A lot of torque is unnecessary.
Depending on model and polarity, the Vertical balun may loop around another element. This is normal. Form
balun coax until it is close to the boom and secure with a nylon cable tie. Also secure the other balun and the
matching / phasing harness coax with cable ties. Ties should be snug but not crushing or kinking the coax.
11. Use good quality coax and “N” connector for your feedline (see Installation Tips). Secure feed coax near
connector on Junction Block, to provide stress relief. Allow about 60” of coax to hang in a loop between the
rear end of the boom and the reattachment point (at least 12” beyond element tips) on the mast or
crossboom.
Do not
route feedline thru boom to mast plate as exiting antenna here will adversely affect
circular field.
12. The boom to mast plate is normally mounted to the boom at the balance point. Since the feed line represents
significant weight it is best to have it attached and fastened to the boom with cable ties before final mounting
the plate. Use two 1" U-bolts and the stainless nuts and lock washers provided. DO NOT OVER TIGHTEN.
2” U-bolts (and stainless steel nuts / lockwashers) are provided for mounting the antenna to your NON-
CONDUCTIVE mast or crossboom. Other size u-bolts and cradles are available upon request.
THIS COMPLETES THE ANTENNA ASSEMBLY.
INSTALLATION TIPS
1. The 370CP38 is a circular polarized antenna and creates a field in all planes or polarities. Performance
DETERIORATES SIGNIFICANTLY if it is mounted on a metal (conductive) mast or crossboom. A mast or
crossboom of any NON-CONDUCTIVE material must be used. Fiberglass is the prime choice for its strength
and weather resistance. Mount the antenna so that element tips are at least 12” from any conductive
material (mast, tower, feedline, etc.).
2. Recommended feedlines, in order of preference:
Andrews or Celwave 1/2” hardline
Times LMR-400 or Belden 8214
Try to keep the cable run to under 100 ft. to prevent excessive signal loss.
3. To maintain proper phasing when stacking two or more antennas, mount each with the same orientation of
Driven Element Blocks. DO NOT MOUNT IN MIRROR IMAGE. See the Specification Sheet for stacking
distances. For more detailed stacking information contact M
2
.
370CP38 ASSEMBLY MANUAL
