SUPER CHOKER™

601863905 - SUPER CHOKER™
+3

Bullet 50:450 (9:1) HF Unun, 1.8-61 MHz, 500/1500 Watts, End Fed Long Wire Antennas

Bullet-9U-500
$79.95
In stock
1
Product Details
Brand: Palomar Enginees
UPC: Does not apply
MPN: Bullet-9U-500/SBULLET-9U-1500
Type: NEW
Country/Region of Manufacture: USA

The “Bullet” End Fed Antenna Matcher

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), 500 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 random horizontal antenna between two trees or supports.

Our network 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. The Bullet uses all stainless steel connectors and a dual core ferrite 9:1 unun for higher power rating then many competitive products.

We sell the Bullet 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.

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 (16' to choke)

80-40-30-20-17-15-12-10-6

71

50 (42' to choke)

80-60-40-30-20-17-15-12-10

111

50 (37' to choke)

160-80-60-40-30-20-17-15-12-10-6

155

100 (95' to choke)

AM, 160-80-60-40-30-20-17-15-12-10-6

173

100 (80-90' to choke)

If you run more than 500 watts PEP and need a high power 9:1 unun for your end fed antenna, check out the BULLET-9U-1500 or square box CU-9-1500 (1500 watts PEP) or CU-9-5000 (5000 watts 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 50/75 ohm feed line ok (over 35 feet minimum) 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 first counterpoise should 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.The Bullet-80 matching unit is rated for 500 watts PEP for SSB and 150 watts continuous carrier for AM, FM, digital modes, or 375 watts CW. 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 at 500 watts PEP with a 50% duty cycle. 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.

Save this product for later
Display prices in: USD
Super-Choker™ Common Mode Feed Line Chokes

Sometimes you need a high power common mode choke that is super effective and the Super-Choker™ products fill this need very well.   All Super-Choker™ chokes use multiple turns through ferrite cores for higher choking impedance compared to our multi-bead sleeve chokes which only use one turn through multiple cores.  Different ferrite mixes and turns ratios are used to optimize choking impedance in the selected product frequency range.

Super-Choker™ chokes are manufactured with 1/2″ 52 ohm coax cable (rated for full amateur radio legal limit of 1500 watts continuous (or the capacity of the coax cable at the selected frequency – good for over 5KW on 4 MHz into a matched load for example) with PL-259 connectors that can be connected to your coax feed line with simple double female barrel connectors.

Super-Choker™ chokes are ideal for high power stations and are very effective for keeping common mode current off the feed line on verticals, dipoles, and loop antennas at their feed point and also for choking coax lines at the station input to reduce common mode noise picked up by the outside of the coax braid between the feed point and the station entrance.

 

Ferrite core kits are available separately if you want to supply your own coax feed line.

 

 

Super Choker™ Case History:

I run an 80 meter loop antenna about 30 feet in height and have previously been using a coaxial balun common mode choke of 25 turns of RG-213 on a 6 inch form attached about 6 feet under the corner feed point of the loop (configured in a triangle).  Using a Dentron 3000 antenna tuner I was able to tune all the ham bands and the lowest SWR was about 1.4 on most bands.  The antenna feed line was led away from the corner of the loop and was not under the loop.  Feed line length was about 105 feet as measured on the Aim 4170-TDR function.

I first placed a Super Choker™ 8010 at the antenna tuner leaving the coaxial balun in place.  As I retuned the antenna tuner, the first thing I noticed was that I could now tune down to 1.1:1 on 80, 40 and 20 meters and I could not do that before.  The noise level which had been running about S7 on 40 meters during the day had dropped to about S6 on my TS-870 receiver.  I was pleased that the reflected power was now almost nil and the noise level was lower. 

I then took the next step and replaced the coaxial balun and Super Choker 8010 with a Super Choker™ 16040 in series with a Super Choker 4010 for maximum choking power from 80-10meters.  The antenna tuning was about the same but now the SWR was 1.0:1 on 80-10 meters and the noise level on 40 was down to S5.  I tuned up on 20, 15 and 10 meters and worked a couple of JA’s and noticed that the noise level on 10 and 15 was not even S1 – something I had not experienced before on the 5 acre plot of land we call home. 

What a welcome relief to find such a simple solution to RF feedback I had experienced and I got a lower noise level to boot! 

Now to plan that 160 meter loop!  I wonder what Krusty ole Kurt would use?

Bob, AK6R