JK Antennas JK-401 User manual

JK-401
40M Hi-Q Coil Loaded Rotatable Dipole
2018 Version
72 Grays Bridge Road, Unit D, Brookfield, CT 06804
845.228.8700 (TEL) ▪845.279.5526 (FAX) ▪i[email protected]
LAST UPDATED: 02-01-2018

JK Antennas Limited Warranty and Liability
JK Antennas (“Manufacturer”) warrants to the original purchaser that this product will be free from defects in
material, and workmanship for a period of one (1) year from the date of purchase. The determination of
whether any part or parts will be covered by this limited warranty and whether any part or parts will be
repaired, replaced or refunded will be solely determined by JK Antennas. Such determination will be made
following evaluation of claim of alleged defect and subject to evaluation of possible misuse, abuse,
unauthorized modifications, extreme weather conditions or improper installation. This warranty does not
cover delivery, transportation, installation or any other costs that may be incurred from any defect.
The purchaser, final customer, installer and user of these products individually and collectively acknowledge
that these products can cause injury or death and individually and collectively accept full responsibility and
liability for any and all personal and property damage (direct, indirect and punitive) caused during installation
and subsequent use.
Copyright Notice
This publication is Copyright ©2017 by JK Antennas. All rights reserved.
No part of this publication or addendum or attachments may be reproduced, stored in a retrieval system or
transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise,
without prior permission of JK Antennas.
WARNINGS
Installation of this antenna near power lines is dangerous. Contact with any high voltage power lines
could result in electric shock or loss of life. Do not install this antenna where there is any possibility
that the antenna or any part of the supporting structure could come in contact with power lines.
Also ensure that no persons or pets can come in any contact with the antenna after it is installed.
Dangerous voltages can exist on the antenna when it is in operation and no part of the system is
insulated to prevent shock.
Consult with FCC OET Bulletin 65 to properly evaluate whether the chosen installation site for this
antenna will comply with the FCC guidelines for human exposure limits to radio frequency electro-
magnetic fields.
This antenna structure is not designed to be used as a support structure. No persons or objects
should be supported by or suspended from the antenna structure at any time.
Because most antenna systems are installed at high heights, the installed location must take into
account that falling debris may pose a hazard to humans, animals and property on the ground below.
Be aware of and follow all local codes and ordinances when installing this antenna.

TOOLS REQUIRED
This antenna uses all SAE standard tool sizes. Metric fasteners are not used on this antenna. Ensure hex keys
used are SAE sizes to avoid stripping the socket cap screw heads.
Size
Description
5/16”
Nut driver, socket or wrench (for #6-32 nylon lock nuts)
11/32”
Nut driver, socket or wrench (for #8-32 nylon lock nuts)
3/8”
Nut driver, socket or wrench (for #10-24 nylon lock nuts)
7/16”
Nut driver, socket or wrench (for 1/4-20 nylon lock nuts)
9/16”
Nut driver, socket or wrench (for 5/16-18 nylon lock nuts)
7/64”
Allen wrench / Hex Key (for 6-32 socket head screws)
9/64”
Allen wrench / Hex Key (for 8-32 socket head screws)
5/32”
Allen wrench / Hex Key (for 10-24 socket head screws)
3/16”
Allen wrench / Hex Key (for 1/4-20 socket head screws)
9/16"
Socket and ratchet (preferred), or combination wrench, or adjustable wrench (for 3/8-16
Bolts.)

JK401 –Hi-Q Coil Loaded Rotatable Dipole
ASSEMBLY GUIDELINES
1. Open the boxes and lay out the elements, hardware kits and parts
2. Using the parts list at the end this document, check to make sure all tubing, hardware kits and parts
are included (extra numbers of bolts, screws, nuts and washers are included)
3. The use of Penetrox or Noalox or any other Anti-seize/Anti-Oxidant compound is HIGHLY recommended
during installation of this antenna. Use a drop or 2 of this anti-seize paste on all screws before fastening.
This will prevent the stainless-steel hardware from accidently locking up. Also a drop or two of the anti-
oxidant paste on the element transitions will prevent corrosion in the joints as well ensure long lasting
electrical performance.
The document has been separated into different assembly sections based on the packaged hardware kits.
While it is recommended to assemble in the order presented, please adjust as needed based on your working
conditions and assembly area.
STEP 1: Mast Plate Assembly
The 1st step is to assemble the small “L” shaped mast plate to the Element Channel. The small Mast Plate has 2
holes that will match up with the larger center holes on the topside of the 40M Element Channel. Attach the
plate to the channel using the hardware included in the Mast Plate to Channel Kit.
STEP 2a: Element Center Section Assembly
The 40M Dipole Element center section is comprised of two (2) 3-ft long aluminum tubes with an outer
diameter of 1-3/4", one (1) solid fiberglass rod (1.5”OD), and the hardware found in the 40M Dipole Element
Hardware Kit.

1) Slide one end of the fiberglass rod inside the end of one aluminum tube and align the holes.
2) Place the shorter screw on the hole away from the center and tighten using a nylon nut.
3) Place the longer screw through the hole closer to the center with a serrated lock washer on
each side and tighten with a nylon nut.
4) Do the same on the other side so that the fiberglass rod has aluminum tubes attached on both
sides.
Once assembled, the Element center section can be mounted onto the element channel. (The above picture
shows the Balun “L” straps attached to the dipole element center screws.)
STEP 2b: 40M Element to Element Channel Assembly
The element center section is attached to the Element Channel using two (2) Black Polyamide Clamps and the
hardware from the Element to Element Channel Kit. When mounted on the mast, the open section of the
channel will face down (toward the ground) so that the black clamps are visible.
Before applying final torque to the black clamps, there are several alignments that must be completed:
1) Align the element center section tube exactly in the center of the element channel.
2) Align the tube so that when screws are used to attach the next taper, the screw heads will face
up (towards the sky).
3) When mounting the center section, make sure that the exposed screws in the center face away
from the Element Channel (down, towards the ground).
4) Optional & Recommended : Twist the center section to point the screws at 45-degrees. This
will enable the balun to be mounted as shown in the picture under the balun assembly detailed
on Page 12 in STEP 3.

After the above alignments are completed, tighten the screws on the black clamps evenly, alternating
between each bolt. Do not apply all the torque to one bolt at a time, as this raises the chances of galling
occurring when the opposite bolt is tightened. The gap between the blocks should just close when the torque
is correct, and there should be an even amount of thread sticking out above each nut. Do NOT continue to
add additional torque after the gap closes.
CAUTION: Continuous over-tightening can cause the screw-head to jam through the black clamps holes.
40M center sections mounted on element channels
STEP 2c: 40M Coil Assembly
Each 40M coil assembly is comprised of two 1.25”OD aluminum tubes, one fiberglass rod, one coil, and the
appropriate screws, nuts, serrated lock washers and silicone tape (Coil Hardware Kit).
1.25”CF = 36” long tube – 4 holes on the tube
1.25”CB = 18” long tube – 3 holes on the tube
The fiberglass rod has 4 holes, which are 1/4” holes. The outside holes from
the center and are used for the mechanical mounting of the tubing to the
fiberglass. The 1/4” inside holes are used for mounting the coil.
NOTE: Always use an anti-oxidant (Penetrox) while tightening the screws and nuts.
1) Starting with either the CF or the CB tube, insert the fiberglass rod and
line-up the holes. Attach the tubes to the rod through the ¼” (outside)
holes using the provided ¼-20screws and ¼-20 nylon nuts.
2) Repeat on the other side of the fiberglass rod with the remaining tube.
Once completed, the section should look like the picture below, with the
1/4” holes still open.

10-24 holes (outside) to attach fiberglass rod to aluminum tubes
1/4" holes (inside) to mount the coil
Now, to attach the coils, follow these steps:
3) Place a serrated/tooth washer (LW14ExT) onto a 1/4"-20 screw, and insert into one of the
1/4”holes on the fiberglass rod/tube assembly.
4) Add another serrated/tooth washer onto the screw on the far side of the rod, and finish with a
1/4-20 nylon-nut. Tighten as far as you can, stopping just short enough to still allow the screw
to rotate freely.
5) Attach a 1/4-20 plain hex nut and turn it until it reaches the nylon nut.

6) Follow these same steps with the remaining hole on the other side of the fiberglass rod, but this
time insert the screw from the opposite side of the rod.
7) Wrap the provided silicone tape over the exposed section of the fiberglass rod (this tape has no
adhesive, so it only bonds to itself –stretch and wind the tape over the exposed section, using
approximately 24 inches or less of tape on each rod).
8) Slide the coil onto the assembly; thread the 10-24 screw four to five times directly into the coil
standoff.
9) GENTLY tighten the hex-nut over the
standoff to act as a jam nut.
10) Do the same on the other side.
11) Tighten the nylon-nut firm and tight along
the tube.

NOTE: It is very important to have a solid mechanical
connection, with the nut and screw making a tight
contact over the tubing. Visually inspect the coil
assembly for any twists or non-symmetry while
tightening these nuts. Adjust them carefully by pulling
them back into place. Repeat this same process for all
the coil assemblies.
The total assembled length of the “coil assembly” is
approximately 59-5/8”.
NOTE: While tightening, take care to NOT put too much
pressure over the coil standoffs. We recommend that
you hold the standoff with pliers or a wrench to
prevent any excess pressure being put on the coil joint
to the standoff while tightening the jam-nut.
STEP 2e: Element Taper Assembly
Once the 40M center section has been mounted, and the coil sections have been assembled, the remaining
tubes can be sleeved in to complete the tapered element sections.
40M: The 40M element has eight (8) tapered aluminum sections on each side of the 1.75” center
section, ranging from 1.5” (largest) to .375” (smallest).
1) Slide 6 inches of the 1.5” OD tube into the center section tube and align the holes. Attach using the
appropriate hardware (40M Element Hardware Kit) as shown in the table below. (Use a drop of anti-
seize paste on all screws).
Transition
Screw Size
Nylon Nut Size
1.75” – 1.5”
SH1024-4
NN1024
1.5” – 1.25”
SH1024-3
NN1024
1.25" - 1"
SH1024-1
NN1024
1" - .875"
SH832-3
NN832
.875" - .75"
SH832-3
NN832
.75" - .625"
SH832-1
NN832
.625" - .5 Slit"
SH632
NN632
.5" Slit - .375"
HC-2
none
2) Slide the CF side of the 40M coil assembly (1.25” tube) into the 1.5” OD tube and attach.
Important : The 1.0”OD tubing has 2 different hole diameters at each end. The regular hole side
goes into the 1-1/4” tubing and the counterbore single hole side towards the 0.875”OD tubing.