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Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 100 Watts, End Fed Long Wire AntennasProduct DetailsBrand: Palomar EngineesMPN: Bullet-9U-100Type: NEWCountry/Region of Manufacture: USAThe “Bullet” End Fed Long Wire Antenna Matcher - 100 Watts PEP/Digital
The key to end fed antenna success is the matching network interface between the long wire antenna and the coax feed line and feed line choke at the transceiver. Palomar Engineers employs a dual core matching system that offers wide bandwidth (1.8-61 MHz), 100 watt PEP rating, and a connection for a counterpoise or ground if desired.
The antenna can be used as a sloper, “L” with a vertical section and a longer horizontal section, or as a horizontal or sloper antenna between two trees or supports. 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.
We sell the Bullet matching unit separately so you can add you own wire type and length (see table of suggested lengths below) or you can purchase a complete antenna system including wire and end insulator. Remember you also need a feed line choke like the easy adjustable snap on SOFLC.
For best results we recommend that the coax feed line be at least 1/4 wavelength on the lowest operating frequency 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.
Suggested wire lengths (measured from Bullet feed point):
Bands Covered (meters)
Wire Length (feet)
Minimum Coax Length (feet)
40-6
41
25
80-6 with tuner
71
50
80-8 (wider on 80)
111
100
160-6
155
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 (feet).
If you need a higher power 9:1 unun for your end fed antenna, check out the Bullet-9U-500, SBullet-9U-1500, or the CU-9-5000 (5KW PEP)
Installation
For best results raise the Bullet matching unit as high as possible (use a tree or vertical support) and then extend the antenna wire horizontally or as an “L” (horizontal with vertical 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 (see typical configurations below).
Antenna Length Modifications: For best results, chose a length from the table above as these lengths will form a non-resonant antenna for the amateur bands indicated.The antenna length should NOT be ¼, 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 a 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 side of the matching unit is in the range of 200-600 ohms and when divided by 9 will be in the range of your transceiver antenna tuner.
Any length of 50 ohm feed line ok (over minimum counterpoise length) 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 of one or more ¼ wavelength counterpoise(s) connected to the ground 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
Use a good quality 50 ohm cable adequate for the power level of your station (RG-8X will easily handle up to 1000 watts PEP). The Bullet-9U-100 matching unit is rated for 100 watts PEP for SSB and 100 watts for 100 watts CW/FT8. If the matching unit becomes warm to the touch after transmitting at high power, reduce the power output or the internal matching unit may become damaged.
Testimonial
Hello, Bob:
I am e-mailing to tell you how impressed I am with the Bullet-9U I received on 3/11/19. I immediately threw a 44 foot wire across my tile roof (in Florida) and began to tune up on 20 meters CW. I was running only about 15 watts to tune the wire and immediately, a station in Ontario came back with "579".) I got down to a 1.5:1 match and increased power to 100 watts. I heard a ham in Croatia calling CQ and got a "599" from him. Switched to 40 meters and before I could tune up, with about a 5:1 SWR, I was called by a ham in Cuba with a 579! And this with the bands in "poor" condition. I never expected such fantastic results. Thank you for a great product.
Dennis Lazar
W4DNN
Note: See Dennis's QST article in February 2020 QST Magazine for more details.
NOTE: We rate our Bullet baluns (and ununs) VERY conservatively with a 50% duty cycle as used with digital (FT8) modes. Some manufacturers selling low cost baluns may use a 5% duty cycle for their PEP rating to make it appear you get a higher rated balun for a lower price, but you may in fact be getting be getting less. Their 1500 watts PEP really means 75 watts continuous or 150 watts at a 50% duty cycle compared to our 250 watts at 50% duty cycle. Our baluns typically cover a larger frequency range under 2:1 SWR which make your transceiver happy and probably will last longer with less electrical stress.
Remember we over engineer our products, to out perform our competition - just compare the weight of our baluns to theirs and you will know we put much more into our products so you don't have to worry about failure at a critical moment.
Tutorials
The “Bullet” End Fed Long Wire Antenna Matcher - 100 Watts PEP/Digital
The key to end fed antenna success is the matching network interface between the long wire antenna and the coax feed line and feed line choke at the transceiver. Palomar Engineers employs a dual core matching system that offers wide bandwidth (1.8-61 MHz), 100 watt PEP rating, and a connection for a counterpoise or ground if desired.
The antenna can be used as a sloper, “L” with a vertical section and a longer horizontal section, or as a horizontal or sloper antenna between two trees or supports. 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.
We sell the Bullet matching unit separately so you can add you own wire type and length (see table of suggested lengths below) or you can purchase a complete antenna system including wire and end insulator. Remember you also need a feed line choke like the easy adjustable snap on SOFLC.
For best results we recommend that the coax feed line be at least 1/4 wavelength on the lowest operating frequency 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.
Suggested wire lengths (measured from Bullet feed point):
|
Bands Covered (meters) |
Wire Length (feet) |
Minimum Coax Length (feet) |
|
|
40-6 |
41 |
25 |
|
|
|
|
|
|
|
80-6 with tuner |
71 |
50 |
|
|
80-8 (wider on 80) |
111 |
100 |
|
|
160-6 |
155 |
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 (feet).
If you need a higher power 9:1 unun for your end fed antenna, check out the Bullet-9U-500, SBullet-9U-1500, or the CU-9-5000 (5KW PEP)Installation
For best results raise the Bullet matching unit as high as possible (use a tree or vertical support) and then extend the antenna wire horizontally or as an “L” (horizontal with vertical 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 (see typical configurations below).
Antenna Length Modifications: For best results, chose a length from the table above as these lengths will form a non-resonant antenna for the amateur bands indicated.The antenna length should NOT be ¼, 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 a 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 side of the matching unit is in the range of 200-600 ohms and when divided by 9 will be in the range of your transceiver antenna tuner.
Any length of 50 ohm feed line ok (over minimum counterpoise length) 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 of one or more ¼ wavelength counterpoise(s) connected to the ground 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
Use a good quality 50 ohm cable adequate for the power level of your station (RG-8X will easily handle up to 1000 watts PEP). The Bullet-9U-100 matching unit is rated for 100 watts PEP for SSB and 100 watts for 100 watts CW/FT8. If the matching unit becomes warm to the touch after transmitting at high power, reduce the power output or the internal matching unit may become damaged.
Testimonial
I am e-mailing to tell you how impressed I am with the Bullet-9U I received on 3/11/19. I immediately threw a 44 foot wire across my tile roof (in Florida) and began to tune up on 20 meters CW. I was running only about 15 watts to tune the wire and immediately, a station in Ontario came back with "579".) I got down to a 1.5:1 match and increased power to 100 watts. I heard a ham in Croatia calling CQ and got a "599" from him. Switched to 40 meters and before I could tune up, with about a 5:1 SWR, I was called by a ham in Cuba with a 579! And this with the bands in "poor" condition. I never expected such fantastic results. Thank you for a great product.
Note: See Dennis's QST article in February 2020 QST Magazine for more details.
NOTE: We rate our Bullet baluns (and ununs) VERY conservatively with a 50% duty cycle as used with digital (FT8) modes. Some manufacturers selling low cost baluns may use a 5% duty cycle for their PEP rating to make it appear you get a higher rated balun for a lower price, but you may in fact be getting be getting less. Their 1500 watts PEP really means 75 watts continuous or 150 watts at a 50% duty cycle compared to our 250 watts at 50% duty cycle. Our baluns typically cover a larger frequency range under 2:1 SWR which make your transceiver happy and probably will last longer with less electrical stress.
Remember we over engineer our products, to out perform our competition - just compare the weight of our baluns to theirs and you will know we put much more into our products so you don't have to worry about failure at a critical moment.
