Directive Systems & Engineering DSE945LYRM User manual

DSE945LYRM Rev 10/20
Directive Systems & Engineering
2702 Rodgers Terrace
Haymarket, VA 20169-1628
www.directivesystems.com
703-754-3876
9cm Loop Yagi (Rear Mount), Model DSE945LYRM
SPECIFICATIONS
Frequency range: 3.40 to 3.48 GHz Gain: 20 dBi
Number of elements: 45 3 dB Beamwidth
Boom length: 60 inches (E plane): 16º
Boom diameter: 0.5 inches F/B ratio: >20 dB
Mast diameter: 1 1/2 inches max Maximum Power: 100 W average
Weight: (assembled) 1.5 pounds Stacking distance: 9 inches’ vertical
Connector: Type-N female 9.8 inches’ horizontal
Note: All hardware is Stainless Steel unless otherwise noted.
BEFORE INSTALLING YOUR NEW ANTENNA, PLEASE BE SURE
TO READ THE ENCLOSED WARNING PAMPHLET.
ASSEMBLY INSTRUCTIONS
1) Unpack the antenna and locate the hardware package. Antennas are shipped in two
sections. Assemble the boom by removing the last three directors from the rear (longer) boom
piece. These loops are D22, 23 &24, and are of similar size. Insert front boom piece into rear
boom piece so that the orientation lines are aligned. Now insert D22 thru 24 into their
respective mounting holes and tighten.
2) Straighten any misaligned elements and re-tighten if necessary. But do not touch R1,
DE or D1, as these have been factory set for minimum SWR.
3) Attach the boom to mast plate to the boom with the hardware provided. Install the U-bolts
so that the mast comes up directly under the boom.
4) Attach the feed line, and tape it to the bottom of the boom. The connector should be sealed
with electronic grade RTV or equivalent.
5) The antenna SWR has been adjusted at the factory for less than 1.5:1 VSWR.
Additional tweaking can be accomplished by changing the shape of the driven element slightly
and by adjusting the distance between the driven element andR1 and D1. R1 is the reflector
closest to the driven element. NOTE: Do not attempt this adjustment unless the proper
equipment and qualified personnel are available.

P a g e | 2
DSE945LYRM Rev 10/20
6) If antennas are to be stacked, see "Instructions for Stacking Loop Yagis".
Observe the drawing below to assemble the antenna to your mast. Install coax and
weatherproof your connection with RTV or equivalent. Tape coax to mast.
DSE945LY BOOM TO MAST MOUNT AND CONNECTOR DETAIL
FOR BEST RESULTS, ORIENT ANTENNA AS SHOWN WITH ELEMENTS LOCATED
BELOW THE BOOM TO PREVENT DAMAGE FROM OVERWEIGHT BIRDS!
DO NOT, UNDER ANY CIRCUMSTANCES, APPLY ANY TYPE OF SEALANT OR COATING TO THE
DRIVEN ELEMENT, T-ARMS OR CONNECTOR ASSEMBLY, OTHER THAN KRYLON®
CLEAR COAT. ANY OTHER COATING WILL ADVERSELY AFFECT THE SWR AND VOID YOUR
WARRANTY.
Directive Systems Warranty Policy
All Directive Systems antennas are built with the finest materials available. We take great pride in building a
quality product that will give years of good service and performance. If there is a defect in materials or
workmanship within 90 days of purchase, Directive Systems will repair or replace the defective part, free of
charge, to the original purchaser. DO NOT RETURN ANYTHING WITHOUT PRIOR AUTHORIZATION
FROM DIRECTIVE SYSTEMS. Please contact us either by phone or email describing the problem and we
will work to resolve it.
If, after examining a new antenna you received, you are not satisfied, contact us immediately for return
authorization and refund. ANY ANTENNA THAT HAS BEEN MODIFIED WILL BE SUBJECT TO A
RESTOCKING CHARGE. IF AN ANTENNA IS SO MODIFIED AS TO MAKE IT UNUSABLE, DIRECTIVE
SYSTEMS RESERVES THE RIGHT TO REFUSE TO ACCEPT THE ANTENNA FOR RETURN.