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Palomar CMNF-500 Manual

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Need a high performance, multi-band, stealthy antenna system that is easy to setup and use? Get the
Bullet-9 matching unit, the antenna wire and insulator all in one convenient package (great for HOA
restricted areas, camping and portable operations) and remember to add the feed line choke.
One of the most popular antennas today is the end fed long wire due to
its ease of installation, portability and stealth in various installations. It
can be a condo dweller's only access to the world of ham radio or the
best alternative for a backpacking SOTA (Summits on the Air), NPOTA
(National Parks of the Air), mountaintop expedition, field day or
portable outing. Excellent performance for permanent installations.
The antenna is simple to deploy, folds up easily
for transport, and weighs under a pound, yet,
with the 71 foot included wire, can work the 80-
10 meter bands easily with the built in antenna
tuner of most current day transceivers.
The 41 foot Backpacker Bullet antenna is super
compact, uses a coax counterpoise allowing 40-
6 meter operation and the whole antenna kit fit in a small bag!
The key to the antenna's success is the highly efficient proprietary
antenna matching unit between the long wire antenna and the coax feed
line to the transceiver. The Bullet-9U-500 antenna matcher employs a
dual core broadband transformer for wide bandwidth (1.8-61 MHz), a
conservative 500 watt PEP rating, an easy on/off antenna wire
connector, a connection for a wire counterpoise if used, and a SO-239
female coax connector for easy attachment of coax cable (50 or 75 ohm
is ok). Note: Bullet may naturally rattle when shaken due to an internal
frequency compensation bead on the output lead to the top eyebolt.
BULLET-9U-500, 9LF(Low Frequency) Matching Unit
Our antenna matching network is called the
"Bullet" because of it shape and its
effectiveness at taking down or contacting
distant (DX) stations all over the world
under the right conditions.
We sell the Bullet matching unit separately
as the Bullet-9U (1.8-61 MHz) or 9LF (.02-
30 MHz) for VLF use down to 200 KHz.
Simply add you own wire (see table of
suggested lengths below) or you can
purchase
including Bullet, antenna wire, and end
insulator. The matching unit is available in 100/500/1500/5KW PEP.
For best results we recommend that the coax feed line be at least 50% of
the antenna wire length since the coax braid is used as a counterpoise if
you don't use the external counterpoise terminal on the matching unit.
We also recommend a feed line choke at the end of the coax feed line
near the radio to prevent RFI common mode current from interfering
with the radio. A simple ferrite ring (Part# EFFLC) with 8-10 turns of
a
complete
antenna
system
Ham Radio Antenna
Application Notes
BULLET End Fed Long
Wire Antenna
Antenna Tip Sheet 2022
the coax line or a large diameter snap on choke (SOFLC)with 5 turns
will work very well on RG-8X (1/4" cable) up to power levels of 1500
watts or use the MC-1-3000 or CU-1-1500/5000 cube choke with side
mounting tabs for larger coax cable. Choke distance from the Bullet-9U
per the table in this report.
Installation
The Bullet antenna wire can have many configurations. For best results,
extend the antenna wire horizontally or as an "L" (horizontal "tail" with
vertical matching unit end drop). The antenna may also be deployed as
a sloper with the Bullet matching unit at the top (best) with the wire
sloping toward the ground (with the end high enough to avoid contact
by humans or animals), or at the bottom of the sloper with the antenna
wire rising to a higher point.
successful in many portable installations is shown below:
Additional Typical Antenna Configurations:
Antenna Length Modifications
For best results, chose a length from the table below as these lengths
will form a non-resonant antenna for the amateur bands indicated. The
antenna length should NOT be ¼ or ½ wavelength on any frequency
that you transmit as the impedance will be very high (or low) and will
not transfer through the matching unit at favorable impedance to your
antenna tuner. The theory of the antenna length is to make the antenna
non-resonant on any amateur band so that the impedance at the antenna
A typical setup which has proven

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Summary of Contents for Palomar CMNF-500

  • Page 1 Ham Radio Antenna Application Notes BULLET End Fed Long Wire Antenna Antenna Tip Sheet 2022 Need a high performance, multi-band, stealthy antenna system that is easy to setup and use? Get the Bullet-9 matching unit, the antenna wire and insulator all in one convenient package (great for HOA restricted areas, camping and portable operations) and remember to add the feed line choke.
  • Page 2 Counterpoise Required A simple 500 Watt PEP, high choking power Common Mode Noise Filter (Part# CMNF-500-50) is pictured below: Ideal: In almost all cases you can use the outside braid of the coax feed line as the single counterpoise for this antenna. See required lengths in the above table.
  • Page 3 Bullet Backpacker 41 – all horizontal slope down from 30 feet to 20 feet. Coax choke at 16 feet from matching unit, coax noise filter installed at radio end of coax. No external counterpoise. May need tuner on some bands. Feed point at 41/(41+16) = 72% of total length. Bullet-41 application note: AK6R has used this antenna to work many countries on FT8 on all bands from 40-10 meters.
  • Page 4 Bullet 71 Inverted L (vertical 25’, horizontal 46’, Bullet-9U (2 feet above ground) – 100 Feet coax, choke at 50 feet from antenna feed point only – no separate counterpoises wires. Total antenna length = 71 + 50 = 121 feet.
  • Page 5 Bullet 111 horizontal sloper – 100 Feet coax, choke at 37 feet from antenna feed point only – no separate counterpoises wires. Total antenna length = 111 + 37 = 148 feet. Feed point at 111/148 = 75% of total length; coax braid counterpoise length is 25% and adjustable to fine tune with SOFLC.
  • Page 6 General Notes For antennas over 71 feet, use 100 feet coax minimum and place choke in a position as shown in table below. This choke position will be a good starting point for tuning your antenna on the bands you want to operate. Here are some examples of actual antenna wire length and choke placement for the antenna SWR plots shown (units are in feet and % of total antenna length including counterpoise): Antenna Wire length (feet/%) Antenna feed point to choke...
  • Page 7 Tuning Your Bullet Antenna The Bullet antenna configurations shown in this manual have been used successfully by many radio amateurs around the world, however your installation geometric shape, height, soil conditions, and coax cable length may be different and your SWR results may not match the ones shown or you may have a higher then wanted SWR on a particular band or bands.
  • Page 8 Disclaimer: No guarantee or liability is either expressed or implied pertaining to damages to persons, property, or equipment in the installation or use of Palomar Engineers, Inc. antennas. Use caution when working near power lines or any power source. If part of the antenna, feed line or antenna mast comes into contact with a power line or power source of any type, it may result in serious injury or death.