Directive Systems & Engineering DSE3347LYA User manual

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DSE3347LYARev12/13
DirectiveSystems&Engineering
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915MHzLoopYagi,ModelDSE3347LYA
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SPECIFICATIONS
Frequency range: 910-930 MHz Gain: 20.5 dBi
Number of elements: 47 3 dB Beamwidth
Boom length: 216 inches (E plane): 14.4º
Boom diameter: 1 inch F/B ratio: ൐20 dB
Mast diameter: 2 inch max Maximum Power: 550 W average
Weight: (assembled) 13 pounds Stacking distance: 38 inches vertical
Connector: Type N female 41 inches horizontal
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PARTSLIST
Quantity Description
3 boom sections
1 hardware package
2 sub-boom splice shells 6 ¾” x 1”
2 sub-boom sections 53” x ¾” square
1 boom to mast plate for 2” U-bolts
2  sub‐boomplates3”x4”
2 2” U-bolts with hardware & saddles
ASSEMBLYINSTRUCTIONS
1) The antenna is shipped in three boom sections. There are alignment marks to assure
proper assembly. The mid boom has a long rectangular bracket attached. This is the midpoint of
the antenna at D21. The front and rear sections have shorter 3 3/4" brackets attached at D13 &
D33. Assemble the three sections together so that the alignment marks match. You will have to
remove D17 & D31 and insert the boom sections into one another, then re install the two loops
and retighten the 4-40 hardware. A1/4" nut driver is required for this.
2) Locate the two 53" sub boom pieces, and note that the rear 53" section has six holes, and
the front section has only four. Check Figure 1 for the correct assembly layout, and lay out the
parts in order. Note that the clamshell brackets have alignment marks to assure proper assembly.
3) At this time assemble the two piece 3/4" sub boom using the supplied 1 1/4" hardware and
clamshell brackets, and do not tighten just yet. Attach the two 3" x 4" sub boom plates (small ones,
with no u-bolt holes) to the sub boom ends, and the short BM brackets on the main boom at
D13&33, using the 8-32 X 1 1/4" screws provided. Do not make them tight yet. Position the 3.5" x
4" boom to mast plate with u-bolt holes, at D21 and the large BM Bracket. Fasten the plate with

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DSE3347LYARev12/13
four 4-40 X 1 1/4" machine screws, nuts and lock washers. This is the balance point of the
antenna. Attach the two 2" stainless U-bolts in the boom to mast plate now.
4) Support the 3347LY on its support mast, with the 2" u-bolts and adjust the main boom until
the boom sag is minimized. Tighten the hardware to lock the sub boom plates in place. There
should be hardly any sag in the boom when this is accomplished. Attach the feedline and tape it to
the bottom of the boom. Seal all coax connections with silicone RTV or equivalent. Coat the back
of the female N connector on the antenna as well.
5) The SWR should be 1.5:1 or better. Additional tweaking can be accomplished by adjusting
the distance between the driven element and R1 or by adjusting the shape of the driven element.
6) If antennas are to be stacked, see "Instructions for Stacking Loop Yagis".
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, free of charge, the
defective part. 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.
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