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DSE945LYRMK Rev 12/20
the shape that gave the best SWR. If you want to further lower the SWR, from the rear of the
antenna, place both your thumbs on the driven loop on either side and gently push it forward
towards D1, you only need to tilt it maybe 3/16” to ¼” and that should drop the SWR to 1.1:1
or less.
Now, GENTLY bend the UT-141 coax after it exits the boom towards the front or rear,
depending on the mounting. You do not want to bend it so tightly that it crushes where it
extends through the bolt. The connector bracket should line up with either D1 or D2 (or the
hole with the circle around it on rear mount antennas), remove that nut and place the
connector bracket on the screw and re-
attach the nut. If the bracket doesn’t line up,
sometimes you have to flip the bracket. Loosen the ¾” nut by holding the connector body with
a 9/16” open end wrench. Remove the connector bracket and flip it.
Connector doesn’t fit Front Mount Connector Rear Mount Connector
4)
Attach the feed line and tape it to the mast. Seal all connections with silicone RTV or
equivalent.
5) Attach the two black end caps and th
is will complete the assembly of your
DSE945LYRMK.
6)
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.
ASSEMBLY TIPS:
The boom diameter is 0.50 inch, and it is drilled for 3-48hardware (no. 34 drill bit). The driven
element hole is 1/4-inch dia. All elements are 0.020-inch-thick and 0.200 inch wide. Note that
the element spacing from D7 on is 1.335 inches. The driven element is installed in the 1/4"
hole in the boom. The feed coaxial cable (0.141-inch semi rigid) goes through the mounting
bolt and is formed in a 90-degree bend so that the connector bracket can be bolted to the
boom at reflector #2 using the R2 hardware. The end opposite the connector is soldered to the
open ends of the brass element. Allow a 3/16" max gap at the feed point. For best match, the
driven element should be approximately 7/8 inches high; this makes it wider than it is tall.
