Palomar CMNF-500 User manual

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.
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 a complete antenna system
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
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. A typical setup which has proven
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

Revised 08/28/2022
side of the matching unit is in the range of 400-600 ohms and when
divided by 9 will be in the range of your transceiver antenna tuner.
Any length of 52 ohm feed line ok (50 feet minimum for 80 meter
operation) but longer feed lines over 50 feet may show reduced SWR on
some bands due to soil conductivity, nearby objects, etc. Due to local
ground conditions, antenna height and feed line length, SWR may vary
and an antenna tuner may be required or some bands to bring SWR at
end of feed line to acceptable levels.
Use a good quality 50 ohm cable adequate for the power level of your
station. The Bullet-9U-500 matching unit is conservatively rated for
500 watts PEP for SSB or 375 watts CW/digital. If the matching unit
becomes warm to the touch after transmitting at high power, reduce the
power output or the internal matching unit may be damaged.
NOTE: The matching unit output is DC grounded to bleed off static
electricity, however it is not RF grounded as the RF signal (at the coax
connector) will see approximately 1/9 of the antenna impedance on the
antenna terminal of the matching unit.
Suggested wire lengths for 1.8-61 MHz operation (measured from
Bullet wire terminal):
Bands Covered
(meters) Wire Length (feet)
Counterpoise
Length (FT)
Minimum
Coax Length
(FT)
40-6
41
16
25
80-40-30-20-17-15-
12-10-6
71
42-50
50
80-60-40-30-20-17-
15-12-10-6
111
37
100
160-80-60-40-30-20-
17-15-12-10-6
155
70
100
For those operators who like to experiment, the following lengths of
wire can also be used: 49, 55, 77, 92, 102, 141-148, 171, 203, 218, 268.
Changing wire length of antenna. You have two choices: extend the
current wire length with additional wire or take off the existing wire by
loosening the wire nut on the halyard hoist and slipping out the fork
spade lug from between the washers and replace with a new length of
wire as needed. Make sure you choose one of the lengths shown in the
above table so as not to have a resonant point in any of the ham bands
which will cause a mismatch for the 9:1 unun. DO NOT UNSCREW
THE HALYARD HOIST EYEBOLT FROM THE BULLET CASE
AS YOU WILL NOT BE ABLE TO SCREW IT BACK IN!!
Counterpoise Required
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. You will need a feedline choke at the suggested length
from the matching unit to stop the flow of RF on the braid and prevent
it from reaching your radio.
In some cases a single counterpoise may not be sufficient to tune in one
or more bands and an additional counterpoise can be added at the stud
on the matching unit. Do not ground the counterpoise stud when using
a counterpoise(s) or radial field. Counterpoise wire(s) close to or laying
on the ground will couple and become radials with reduced efficiency.
Use of one or more random length counterpoise(s) connected to the
counterpoise post of the matching unit may also improve antenna
efficiency and reduce SWR on certain bands. The counterpoise should
not be installed under the horizontal portion of the antenna for best
results. Suggested counterpoise lengths are 15, 24, 37 feet with a 50
foot coax feed and a choke installed 50 feet from the antenna feed point.
Counterpoises can be straight or zig-zagged.
Feed Line Choke Needed
Many different feed line chokes will work with the end fed antenna.
The purpose of the choke is to stop the RF current on the outside of the
coax braid from getting into the radio. In this antenna system, the outer
part of the braid acts as a counterpoise part of the antenna and you need
to suppress the current at the radio end. DO NOT FORGET THIS
REQUIREMENT!
Configurations
This antenna can be installed in a number of different configurations
including vertical, sloper, inverted L or vertical-horizontal-vertical (“n”
style). In general it is better to get the matching unit as high as possible
since the antenna current is highest near the matching unit. Horizontal
antennas and sloper antennas with the matching unit at the high end
work particularly well. Radiation will be perpendicular to the wire on
some bands and in-line with the wire on others depending upon the
frequency of operation. Have fun and experiment with different
configurations! Many different configurations and measured SWR
curves are shown on the following pages.
Coax Noise Filter
Instead of the ferrite ring feed line choke, you may use a coax noise
filter which has the dual purpose of suppressing RF from the
TRANSMITTED signal AND suppressing common mode current noise
picked up on the coax braid during RECEIVE operation.You hear this
“noise” as a higher than normal noise floor on your receiver. Vertical
antennas in general have a higher noise factor due to the vertical
polarity nature of noise sources in the neighborhood.
A simple 500 Watt PEP, high choking power Common Mode Noise
Filter (Part# CMNF-500-50) is pictured below:
To install, simply connect the coax line from the antenna to one
connector and add a small coax jumper from the other connector to your
radio. This encapsulated filter is also more durable than the ferrite ring
which can fracture if dropped on the ground. You will still need a feed
line choke at the appropriate distance from the matching unit unless the
noise filter is installed at the correct distance.

Revised 08/28/2022
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. Works very well as sloper and I am amazed how well it works on 30 meters into Europe from
California during late afternoon into nightfall. I have used up to 280 watts on FT8 with this antenna for
extended periods, but have also worked many contacts under 100 watts to test its effectiveness and I am very
pleased with the configuration and simplicity of this installation between two trees. Great antenna for portable
operations like NPOTA, SOTA, Field Day, etc., or for permanent installations like installing in an attic, under
the eaves of a house, along a fence, etc. This is a short, effective and easy-to-hide antenna which gives a
good account of itself on 40-6 meter bands.

Revised 08/28/2022
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. Feed point at 71/121 = 59% of total length
Bullet 71 all horizontal up 25 feet – 100 Feet coax, choke at 42 feet from antenna feed point only gives better
80 meter SWR – no separate counterpoise wires. Total antenna length = 71 + 42 = 113 feet. Feed point at
71/113 = 63% of total length

Revised 08/28/2022
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.
Bullet 155 All Horizontal Average height 30 feet – 100 Feet coax, choke at 95 feet from antenna feed point
only – no separate counterpoises wires. Total antenna length = 155 + 95 = 250 feet. Feed point at 155/250 =
62% of total length; coax braid counterpoise length is 38%.

Revised 08/28/2022
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
length (feet) – fine tune for best
results for you configuration(*)
Total Antenna Wire +
coax length (feet)
41 (72%)
16 (28%)
57 (100%)
71 (63%)
42-50 (37%)
113-121 (100%)
111 (75%)
37 (25%)
148 (100%)
155 (62%)
95 (38%)
250 (100%)
(*) - Choke measurement is from antenna feed point at 9:1 unun coax connector to choke.
Feed line Choke Options
Use Feedline choke EFFLC or SOFLC for RG-8X size cable or choke MC-1-500 (500 watts PEP) or MC-1-3000 (3KW PEP) for larger
coax with UHF connectors.
EFFLC (RG-8X coax not included) –
easiest to adjust length from matching
unit– up to -30 dB suppression
Mini-Choker™ MC-1-500-50 (500 watts
PEP) – up to -38 dB suppression
Maxi-Choker™ MC-1-3000 (3KW PEP) –
up to -48dB suppression
CMNF-1500 (1.5KW) – wall mounting– up
to -38 dB suppression
CMNF-5000 (5KW) – wall mounting – up to
-38 dB suppression
SOFLC - Snap On Feed Line choke (works
on RG-8X (6 turns) or RG-8 (3 turns) up to
38 dB suppression
Wire Pulleys
Split wire pulleys are very useful for installing free running antenna
wire. Use a halyard hoist on first pulley carabiner and free run the
wire from the matching unit
thru the first and any additional pulleys.
Support the wire every 50-75 feet thru a pulley (and separate
halyard hoist/support attachment to the carabiner part of the pulley)
and the antenna will be much easier to raise and maintain in the
future.
Part#: Pulley-1.75

Revised 08/28/2022
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.
So how do you tune the antenna for your installation? First start off with the suggested dimensions for the antenna wire and the choke
placement distance from the matching unit and measure the SWR’s on the various bands. This antenna is tuned by adjusting the
placement of the choke (or length of the counterpoise wire used). Move the choke a couple feet at a time and see if the SWR for the
band or bands improves. You can also add one or more parallel counterpoise(s) off the side stud on the matching unit for a particular
band (s). to fine tune the antenna for particular frequencies.
Do not change the length of the main antenna wire, but rather change the position of the choke on the coax and/or add counterpoises
as needed. They don’t have to be straight just the correct length. Keep them away from the horizontal portion of the antenna so that
the antenna radiation does not couple to the counterpoise lowering the radiation efficiency.

Revised 08/28/2022
BulletAntenna Individual Components
PEP Power
Rating
100 Watt (*)
500 Watt (*)
1500 Watt (*)
5000 Watt (*)
Feed Line Choke
EFFLC
EFFLC or
SOFLC
SOFLC
MC-1-3000 or
CU-1-1500SO
CU-1-5000SO
41’Wire +
Insulator
BWK-41
BWK-41
BWK-41
BWK-41
71’Wire +
Insulator
BWK-71
BWK-71
BWK-71
BWK-71
111’Wire +
Insulator
BWK-111
BWK-111
BWK-111
BWK-111
155’Wire +
Insulator
BWK-155
BWK-155
BWK-155
BWK-155
Use Coax
RG-8X-50
RG-8X-50
RG-8X/RG400/RG-
8/213/LMR400
RG-
8/213/LMR400
Transformer (9:1)
Bullet-9U-100
Bullet-9U-
500
SBullet-9U-1500 or CU-9-
1500
CU-9-5000
9:1 Unun
Transformer
Picture
(*) Power rating are for SSB PEP, Digital (CW/FT8) rating are 50% of PEP ratings
Complete BulletAntenna Systems
Item
100 Watt
500 Watt
1500 Watt
5000 Watt
Antenna Length (FT)
Part #
Part #
Part #
CU-1-5000SO

RG-8X-50



Transformer (9:1)
Bullet-9U-100
Bullet-9U-500
SBullet-9U-1500
CU-9-5000
Feed Line Choke
SOFLC
SOFLC
SOFLC
CU-1-5000SO
Order Part #
(XX=41, 71, 111, 155)
BAS-100-XX
BAS-500-XX
BAS-1500-XX
BAS-5000-XX
Palomar-Engineers.com
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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.