Oct 21, 2012 - With that aside, here are some unique benefits of the J-Pole antenna and the Slim Jim. Use this comparison chart to decide which is better for. I have just modelled both the Slim Jim antenna and J Pole antenna using. Some websites indicate that the only significant difference is that the. Slim Jim has a.
Authentic N9TAX VHF/UHF Slim Jim J-Pole For HT 2m 70cm Antenna 10' Coax
Use with Baofeng, Wouxun, TYT, Yaesu++ See DescriptionBand: VHF$18.24 shippingDirectivity: Omni-DirectionalCustoms services and international tracking providedDIY J-POLE ANTENNA AERIAL FITTING - AIRBAND 2M, 4M, 6M, AMATEUR HAM RADIO JPOLE
This part has 70mm centre to centre spacing for your poles which suits nearly all frequecies for the amateur radio bands. 70mm spacing is fine for frequencies upto a few hundred mhz. DIY J-POLE CONNECTION FITTING.From United Kingdom$15.21 shippingDELUXE MODEL ROLL UP 2M/70CM ROLL UP J-POLE/SLIM JIM ANTENNA WITH 10FT COAX
Baofeng/Wouxoun/Yeasu/Icom/Kenwood/MoreBand: VHF$10.95 shippingDirectivity: Omni-DirectionalAuthentic KB9VBR 2 Meter VHF SLIM JIM amateur ham radio J-Pole base antenna
Trusted by hams world-wide, what makes a KB9VBR antenna better?. I use mine on a daily basis on my Winlink 2000 station. The Slim Jim likes to be mounted high. My experience with it is that you want to get this antenna up at least 20 or 30 feet for it to really perform.Top Rated Plus$27.08 shippingBand: VHFDirectivity: Omni-DirectionalCustoms services and international tracking providedAuthentic N9TAX VHF/UHF Slim Jim J-Pole For HT MURS / GMRS Antenna 10' Coax!
Use with Baofeng, Wouxun, TYT, Yaesu++ See DescriptionBand: VHF$19.51 shippingDirectivity: Omni-DirectionalCustoms services and international tracking providedJ- POLE ANTENNA FOR THE MARINE AND NOAA BANDS
This is a J Pole antenna cut for the MARINE band. 156 to 158 Mhz, and the N.O.A.A weather band (162 Mhz). Antenna is tested at 100w (this is my power limitations. but you can go with 500w easily).Brand: Unbranded$14.56 shippingDirectivity: Omni-DirectionalCustoms services and international tracking providedDELUXE MODEL ROLL UP 2M/70CM ROLL UP ANTENNA WITH 10FT COAX J-POLE/SLIM-JIM
BAOFENG/YAESU/WOUXOUN. MADE TO FIT ANY RADIO!Band: VHF$8.20 shippingDirectivity: Omni-DirectionalAuthentic N9TAX VHF/UHF Slim Jim J-Pole For HT 2m 70cm Antenna 16' Coax
Use with Baofeng, Wouxun, TYT, Yaesu++ See DescriptionBand: VHF$18.09 shippingDirectivity: Omni-DirectionalCustoms services and international tracking provided19” Universal J-Pole J-Mount for Outdoor Antennas, Over the Air HDTV, Scanners
FREE SHIPPING TO ALL 50 STATES INCLUDING APO FPO HI AK$49.10 shippingVHF Base Antenna w/ gain- Stainless Steel J-Pole
PRO-SERIES VHF J-Pole Antenna 132 to 225 MHz. The PRO-SERIES line reinforces that fact. It's the perfect choice for permanent, fixed-station installations. VHF: Specified Frequency /-3.5 Mhz (7 Mhz).Band: UHFDirectivity: Omni-Directional6 Meter J Pole rollup antenna - 24ft RG58 coax. PL259 & 150 Watts PEP
24 feet of RG58U coax cable and a PL259 male coax connector are furnished. The actual antenna length is about 12 feet. All connections are soldered and weather proofed with shrink tubing. Antenna made with 300 ohm ladder line wire.Brand: Unbranded$25.46 shippingBand: VHFDirectivity: Omni-DirectionalCustoms services and international tracking provided2m/70cm Copper J Pole Antenna Heavy duty collapsible Amateur Radio Ham
I often use them at public service events and find them easy to deploy and transport. They are well suited to these situations being that they need no further grounding or counterpoise. They greatly expand the range of a hand held radio.Band: VHF$56.65 shippingDirectivity: Omni-DirectionalUHF Base Antenna w/ gain- Stainless Stl. J-Pole 300-960
Use this antenna anywhere you need an omni-directional, single band, 50-ohm, UHF antenna that throws real gain toward the horizon. PRO-SERIES UHF J-Pole Antenna 300 to 960 MHz. This service is included in the price of the antenna.Band: UHF2 METER COPPER J-POLE (Freedom)
2 METER COPPER J-POLE . Let Freedom ring. Condition is New. Red, white and blue flag painted scheme. All copper construction, with water resistant N female housing. Tuned to 146.5 MHz. Tunable for best SWR and 50 ohm impedance. Ground at mast and bottom of mast for safe operation.Brand: Unbranded$28.21 shippingBand: VHFDirectivity: Omni-DirectionalCustoms services and international tracking provided223 MHz 1.25 METER J-POLE ANTENNA
223 MHz 1.25 Meter copper j-pole antenna.Condition is New. Compact SO239 housing, water resistant. Green and tan color scheme applied to copper surface for added protection. All internal connections are soldered for superior signal transfer. Tuned to 223.00 MHz for lowest SWR. For base station and field operations.Brand: Unbranded$27.81 shippingBand: VHFDirectivity: Omni-DirectionalCustoms services and international tracking provided2 METER COPPER J-POLE ( REAL TREE CAMO COLOR)
2 METER COPPER J-POLE . Condition is New. All copper construction, with black water resistant SO239 housing. Tuned to 146.5 MHz. Tunable for best SWR and 50 ohm impedance. Ground at mast and bottom of mast for safe operation. Tree bark camouflaged color scheme applied to copper surface for added protection. This color is good if you live in a HOA subdivision with strict rules on antennas on your home or yard or for survivalist. This can be put up in a tree to blend in. No one will know you have it. All internal connections are soldered for superior signal transfer. Comes with end caps.This is for base station and field operations.Brand: Unbranded$29.83 shippingCustoms services and international tracking providedAuthentic N9TAX VHF/UHF Slim Jim J-Pole Dual Band MURS/GMRS Antenna jpole!
Use with Baofeng, Wouxun, TYT, Yaesu++ See DescriptionDirectivity: Omni-Directional$17.01 shippingCustoms services and international tracking providedAuthentic N9TAX VHF/UHF Slim Jim J-Pole Dual Band 2m 70cm Antenna jpole
Use with various radios. See DescriptionBand: UHF$17.01 shippingDirectivity: Omni-DirectionalCustoms services and international tracking providedRadiowavz JP6S 6 Meter Portable J-Pole Antenna with SMA Connector and Carry Case
6 foot synthetic line to make it easy to hang almost anywhere. Includes convenient carry pouch. He set out to make one that was more efficient. He did it! This optimized Portable J-Pole antenna can greatly increase the efficiency and coverage of your HT.Top Rated Plus$17.44 shippingBrand: RadioWavzCustoms services and international tracking providedJ- POLE ANTENNA FOR THE 2 METER BAND
Antenna is tested at 100w (this is my power limitations. but you can go with 500w easily). Have a Female SO239 bolted (not riveted or welded) on the antenna to direct feed your coaxial line (50 ohms).Directivity: Omni-Directional$14.56 shippingCustoms services and international tracking providedTrue Dual Band 2M/70CM Stainless Steel J-pole Antenna
Use this antenna anywhere you want an omni-directional antenna that throws real gain toward the horizon. It is especially good for cross-band repeaters, APRS stations, or for rag chewing on SSB on the lower band portions of the band or on the local repeaters.Band: UHF$55.65 shippingDirectivity: Omni-Directional20 Meter all coax J Pole antenna with 16ft. RG58 coax cable PL259 male connector
Its power limit is 250 watts. A 16 foot length of RG58 coax cable and a PL259 male coax connector is furnished as the feed line. All connections are soldered and weather proofed with shrink tubing and/or spray sealant.Brand: Unbranded$30.11 shippingBand: HFDirectivity: Omni-DirectionalCustoms services and international tracking providedSlim Jim J pole antenna for 2 meter 440 -16 ft RG58U coax with ferrite RF choke
INCLUDES 16 FEET OF RG58U LEED-IN COAX CABLE. 16 feet of RG58U lead-in coax cable, PL259 male connector, and RF filter to help keep excess rf out of the shack. The J Pole is one of many half wave antennas that has a tendency to send excess RF energy back down the antenna feedline when SWR readings start to increase.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalSix Meter J Pole rollup antenna 300 ohm ladder line - 16ft. RG58 coax with PL259
16 feet of RG58 coax cable and a PL259 male coax connector are furnished. The actual antenna length is about 13 feet. All connections are soldered and weather proofed with shrink tubing. A small hole is located near the top end of the 300 ohm ladder line so that the antenna can be easily hung from overhead structures, such as a tree.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalVHF UHF Slim Jim J pole 2 meter antenna 24ft coax - range extended version
MAXIMUM RF MAXIMUM WATTS INPUT IS 150 WATTS RMS OR AVERAGE DC WATTS. The basic difference between a standard J Pole antenna and the Slim Jim J Pole antenna is the radiation pattern and the vertical angle of radiation.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional2 meter 440Mhz J Pole Antenna - VHF UHF-24ft RG58 coax cable - PL259 male
Its power limit is 150 watts. All connections are soldered and weather proofed with shrink tubing. A small hole is located near the top end of the heavy duty outdoor 300 ohm ladder line so that this antenna can be hung from any overhead structure.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional6 Meter J Pole rollup antenna - 16ft RG58 coax - PL259 & 150 Watts PEP
Heavy duty outdoor type 300 ohm ladder line is used,16 feet of RG58 coax cable, and a PL259 male coax connector are furnished. The actual antenna length is about 12 ft. All connections are soldered and weather proofed with shrink tubing.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional2 meter 440Mhz J Pole Antenna - VHF UHF-16ft RG58 coax cable - PL259 male
Its power limit is 100 watts. All connections are soldered and weather proofed with shrink tubing. Made with outdoor 300 ohm ladder line wire so that antenna can be hung from any overhead structure.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalVHF UHF Slim Jim j pole 2 meter 440 antenna -16ft coax-range extended version
The basic difference between a standard J Pole antenna and the Slim Jim J Pole antenna is the radiation pattern and the vertical angle of radiation. An apparent gain of 6db is gained when the angle of radiation is pulled downwards towards the horizon and elongated.Brand: UnbrandedDirectivity: Omni-Directional2 Meter J Pole copper antenna- Free shipping included
I make mine to break down into 3 sections for easy storage or transport. Connect the 3 poles and insert the supplied cotter pins, fold them back and mount on just about any support mast you want. They also work very well.Band: VHFor Best OfferDirectivity: Omni-DirectionalVHF UHF Slim Jim j pole 2 meter 440 antenna -16 feet coax with ferrite RF choke
INCLUDES 16 FEET OF RG58U LEED-IN COAX CABLE. The J Pole is one of many half wave antennas that has a tendency to send excess RF energy back down the antenna feedline when SWR readings start to increase.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalSix Meter 52Mhz J Pole rollup antenna with 16ft. lead-in coax and PL259 male.
High quality outdoor 300 ohm ladder line, 16 feet of RG58 coax cable, and a PL259 male coax connector are furnished. The actual antenna length is about 12ft. All connections are soldered and weather proofed with shrink tubing.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalSlim Jim J Pole 144-148Mhz ham radio antenna- Extended range version 6ft. coax
The antenna is a rollup style making it portable for all applications. It features heavy duty 300 ohm outdoor type ladder line, 6 feet of RG58 coax cable, and a PL259 male coax connector. For a closer look at the 300 ohm ladder line, see photo #2 above.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional6 Meter 52Mhz J Pole rollup antenna with 16ft. lead-in coax with PL259 male.
High quality outdoor 300 ohm ladder line, 6 feet of RG58 coax cable, and a PL259 male coax connector are furnished. The actual antenna length is about 12ft. All connections are soldered and weather proofed with shrink tubing.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalRadiowavz JP6B 6 Meter Portable J-Pole Antenna with BNC Connector and Carry Case
6 foot synthetic line to make it easy to hang almost anywhere. Includes convenient carry pouch. He set out to make one that was more efficient. He did it! This optimized Portable J-Pole antenna can greatly increase the efficiency and coverage of your HT.Top Rated Plus$17.44 shippingBrand: RadioWavzCustoms services and international tracking providedSlim Jim 2 meter/440 ham radio antenna - Extends range over standard J Pole
The basic difference between a standard J Pole antenna and the Slim Jim J Pole antenna is the radiation pattern and the vertical angle of radiation. An apparent gain of 6db is gained when the angle of radiation is pulled downwards towards the horizon and elongated.Band: VHFDirectivity: Omni-DirectionalSlim Jim 2 meter ham radio antenna- with extended range over standard J Pole
The basic difference between a standard J Pole antenna and the Slim Jim J Pole antenna is the radiation pattern and the vertical angle of radiation. An apparent gain of 6db is gained when the angle of radiation is pulled downwards towards the horizon and elongated.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional6 Meter J Pole rollup ham radio antenna - 24ft RG58 coax. PL259 - RF Choke
24 feet of RG58U coax cable and a PL259 male coax connector are furnished. Also included is a ferrite RF choke. The actual antenna length is about 12 feet. All connections are soldered and weather proofed with shrink tubing.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional2 meter 440Mhz J Pole ham radio antenna & 6 feet RG58 coax cable & male PL259
6 feet of RG58 lead-in coax cable & male PL259 connector included. This J Pole antenna features heavy duty outdoor type 300 ohm ladder line, a 6 foot length of RG58 coax cable, and a standard PL259 male connector.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalAll coax 6 Meter 52Mhz J Pole antenna with 16ft. lead-in coax cable & PL259 male
This J Pole can be used either in the vertical or horizontal planes. Antenna is made from RG58U coax cable and, 16 feet of RG58 lead-in coax cable. Also included is a PL259 male coax connector. The actual antenna length is about 13ft.Brand: UnbrandedBand: AMDirectivity: Omni-Directional2 METER COPPER J-POLE
2 METER COPPER J-POLE . Condition is New. Has water resistant SO239 housing and can be broken down for portable operation. Ground at mast and bottom of mast for safe operation. SWR 1.0 at 147 range.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional2 METER COPPER J-POLE
2 METER COPPER J-POLE . Condition is New. Blue and white color scheme. Water resistant N female housing. Ground at mast and ground at bottom of mast for safe operation. All copper construction.Brand: UnbrandedBand: VHFDirectivity: Omni-DirectionalVHF UHF Slim Jim jpole 2 meter 440 antenna 24ft coax - range extended version
MAXIMUM RF MAXIMUM WATTS INPUT IS 150 WATTS RMS OR AVERAGE DC WATTS. The basic difference between a standard J Pole antenna and the Slim Jim J Pole antenna is the radiation pattern and the vertical angle of radiation.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional223Mhz 1.25meter J-pole Antenna
223 MHz 1.25 Meter Copper J-pole Antenna. Condition is New. Compact SO239 housing, water resistant. Tree bark camouflaged color scheme applied to copper surface for added protection. This color is good if you live in a HOA subdivision with strict rules on antennas on your home or yard. This can be put up in a tree and blend in. All internal connections are soldered for superior signal transfer. Tuned to 223.00 MHz for lowest SWR. For base station and field operations.or Best Offer2 METER COPPER J-POLE
2 METER COPPER J-POLE . Condition is New. Blue and white color scheme. Water resistant SO239 housing maybe different from picture. Tuned to 146.5 MHz. Ground where antenna mounts to mast and at bottom of mast for safe operation.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional1.25 METER COPPER J-POLE ANTENNA
1.25 METER COPPER J-POLE ANTENNA. Condition is New. Compact SO239 housing, water resistant. Clearcoat applied to copper surface for added protection. All internal connections are soldered for superior signal transfer. Tuned to 223.00 MHz for lowest SWR. For base station and field operations.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional2 METER COPPER J-POLE
2 METER COPPER J-POLE . Condition is New. White and blue paint scheme. All copper construction, with water resistant SO239 housing. Tuned to 146.5 MHz. Tunable for best SWR and 50 ohm impedance. Ground at mast and bottom of mast for safe operation.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional2 meter 440 - 300 ohm ladder line JPole antenna 6ft RG58 coax - PL259 - RF choke
6 feet of RG58 lead-in coax cable with male PL259 & RF Choke. The antenna is a rollup style making it ideal for portable and fixed applications. Antenna features heavy duty outdoor type 300 ohm ladder line, 6 foot length of RG58 coax cable, and PL259 male connector.Brand: UnbrandedBand: VHFDirectivity: Omni-Directional
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J-Pole Antenna.
The J-pole antenna, more properly known as the J antenna,[1] was first invented by Hans Beggerow in 1909 for use in Zeppelin airships.[2] Trailed behind the airship, it consisted of a single element, one half wavelength long radiator with a quarter wave parallel feedline tuning stub. This concept evolved to the J configuration by 1936[3] attaining the name J Antenna by 1943.[1]
- 1Characteristics
- 2Feed and mounting
- 3Variations
Characteristics[edit]
The J-pole antenna is an end-fed omnidirectional half-wave antenna that is matched to the feedline by a quarter wave parallel transmission linestub[1] of Lecher system form.[2] Matching to the feed-line is achieved by sliding the connection of the feedline back and forth along the stub until an impedance match is obtained.[1] Being a half-wave antenna, it provides a small gain over a quarter-wave ground-plane antenna.[4]
Gain and radiation pattern[edit]
E-plane gain measurements of J antenna with respect to reference dipole.
Primarily a dipole, the J-pole antenna exhibits a mostly circular pattern in the H plane with an average free-space gain near 2.2 dBi (0.1 dBd).[5] Measurements and simulation confirm the quarter-wave stub modifies the circular H-plane pattern shape increasing the gain slightly on the side of the J stub element and reducing the gain slightly on the side opposite the J stub element.[5][6] At right angles to the J-stub, the gain is closer to the overall average: about 2.2 dBi (0.1 dBd).[5] The slight increase over a dipole's 2.15 dBi (0 dBd) gain represents the small contribution to the pattern made by the current imbalance on the matching section.[5] The pattern in the E plane reveals a slight elevation of the pattern in the direction of the J element while the pattern opposite the J element is mostly broadside.[6] The net effect of the perturbation caused by quarter-wave stub is an H-plane approximate gain from 1.5 to 2.6 dBi (-0.6 dBd to 0.5 dBd).[6]
Environment[edit]
Like all antennas, the J-pole is sensitive to electrically conductive objects in its induction fields[7] (aka reactive near-field region [8]) and should maintain sufficient separation to minimize these near field interactions as part of typical system installation considerations.[9] The quarter wave parallel transmission line stub has an external electromagnetic field with strength and size proportional to the spacing between the parallel conductors.[10] The parallel conductors must be kept free of moisture, snow, ice and should be kept away from other conductors including downspouts, metal window frames, flashing, etc. by a distance of two to three times the spacing between the parallel stub conductors.[11] The J-Pole is very sensitive to conductive support structures and will achieve best performance with no electrical bonding between antenna conductors and the mounting structure.[12][13]
Feed and mounting[edit]
Construction[edit]
Typical construction materials include metal tubing,[1]ladder line, or twin-lead.[14]
Feed[edit]
The J-pole antenna and its variations may be fed with balanced line.[1] A coax feed line may be used if it includes a means to suppress feed-line RF currents.[12][15] The feed-point of the J-pole is somewhere between the closed low-impedance bottom and open high-impedance top of the J stub.[1][3] Between these two extremes a match to any impedance between the low to high impedance points is available.[1][3]
Mounting[edit]
The J-pole design functions well when fed with a balanced feed (via balun, transformer or choke) and no electrical connection exists between its conductors and surrounding supports.[12][13] Historical documentation of the J antenna suggests the lower end of the matching stub is at zero potential with respect to earth and can connect to a grounding wire or mast with no effect on the antenna's operation.[1] Later research confirms the tendency of the mast or grounding wire to draw current from the antenna potentially spoiling the antenna pattern.[16] A common approach extends the conductor below the bottom of the J-pole resulting in additional and undesirable RF currents flowing over every part of the mounting structure.[12] This modifies the far field antenna pattern[16] typically, but not always, raising the primary lobes above the horizon reducing antenna effectiveness for terrestrial service.[13] J-pole antennas with electrical connection to their supports often fare no better, and often much worse, than the simpler Monopole antenna.[12] A mast decoupling stub reduces mast currents.[16][17][18][19]
Variations[edit]
E-plane gain plots of J antenna variations
Slim Jim antenna[edit]
A variation of the J-pole is the Slim Jim antenna, also known as 2BCX Slim Jim,[20] that is related to the J-pole the way a folded dipole is related to a dipole.[21] The Slim Jim is one of many ways to form a J-Pole.[21] Introduced by Fred Judd (G2BCX) in 1978, the name was derived from its slim construction and the J type matching stub (JIntegrated Matching).[20]
The Slim Jim variation of the J-pole antenna has characteristics and performance similar to a simple or folded Half-wave antenna and identical to the traditional J-pole construction.[21] Judd found the Slim Jim produces a lower takeoff angle and better electrical performance than a 5/8 wavelength ground plane antenna.[20] Slim Jim antennas made from ladder transmission line use the existing parallel conductor for the folded dipole element.[6] In the copper pipe variation, the Slim Jim uses more materials for no performance benefit.[6] Slim Jim antennas have no performance advantage over the traditional J-pole antenna.[6][21]
The approximate gain in the H-plane of the Slim Jim is from 1.5 to 2.6 dBi (-0.6 dBd to 0.5 dBd).[6]
Super-J antenna[edit]
The Super-J variation of the J-pole antenna adds an additional collinear half-wave radiator above the traditional J and connects the two with a phase stub to ensure both vertical half-wave sections radiate in current phase.[22] The phasing stub between the two half-wave sections is often of the Franklin style.[22][23][24]
The Super-J antenna compresses the vertical beamwidth and has more gain than the traditional J-pole design.[25] Both radiating sections have insufficient separation to realize the maximum benefits of collinear arrays resulting in slightly less than the optimal 3 dB over a traditional J-pole or halfwave antenna.[25][26]
The approximate gain in the H-plane of the Super-J antenna is from 4.6 to 5.2 dBi (2.4 dBd to 3.1 dBd).[26]
Collinear J antenna[edit]
The collinear J antenna improves the Super-J by separating the two radiating half-wave sections to optimize gain using a phasing coil.[26] The resulting gain is closer to the optimum 3 dB over a traditional J-pole or halfwave antenna.[26]
The approximate gain in the H-plane of the Collinear J antenna is from 4.6 to 5.2 dBi (2.4 dBd to 3.1 dBd).[26]
E-plane gain patterns of the variations[edit]
The graph compares the E-plane gain of the above three variations to the traditional J antenna.
The traditional J antenna and SlimJIM variation are nearly identical in gain and pattern. The Super-J reveals the benefit of properly phasing and orienting a second radiator above the first. The Collinear J shows slightly higher performance over the Super-J.
Dual-band operation near 3rd harmonic[edit]
The basic J antenna resonates on the third harmonic of its lowest design frequency.[27] Operating a 3/2 wavelengths this way produces an antenna pattern unfavorable for terrestrial operation.[28]
To address the pattern change a variety of techniques exist to allegedly constrain a J antenna operating at or near the third harmonic so only one half-wave is active in the radiator above the stub. All involve the use of a high impedance choke at the first voltage loop.[28] These methods fall short of the goal as choking a high impedance point with a high impedance allows energy to pass the choke.[28][29]
References[edit]
- ^ abcdefghi'Very-High-Frequency Antennas'. Antennas and Antenna Systems (TM 11-314)(PDF). U.S. War Department. 1943-11-30. pp. 163–164. Retrieved 6 May 2016.
- ^ abBeggerow, Hans (1909). 'Zeppelin Antenna'(PDF). Retrieved 28 January 2016.
- ^ abcUS patent 2124424, Laurance McConnell Leeds, 'Antenna System', published 1938-07-19
- ^Huggins, John S. '1/4 Wave Monopole vs. 1/2 Wave J-Pole EZNEC Shootout'. Retrieved 30 January 2012.
- ^ abcdCebik, L. B. 'Some J-Poles That I Have Known Part 1: Part 1: Why I Finally Got Interested in J-Poles and Some Cautions in Modeling Them'. Cebik.Com. Archived from the original on April 22, 2014. Retrieved 1 October 2015.
- ^ abcdefgHuggins, John S. 'Slim Jim vs. Traditional J-pole Antenna'. Retrieved 28 August 2015.
- ^Griffith, B. Whitfield (1962). Radio-Electronic Transmission Fundamentals. New York, NY: McGraw Hill Book Company, Inc. pp. 322–323.
- ^Balanis, Constantine (1982). Antenna Theory. Harper & Row, Publishers, Inc. pp. 116–118. ISBN0-06-040458-2.
- ^Collins, Brian (1984). 'VHF and UHF Communication Antennas'. In Johnson, Richard (ed.). Antenna Engineering Handbook (2nd ed.). New York, NY: McGraw-Hill. pp. 27.21–27.22. ISBN0-07-032291-0.
- ^Griffith, B. Whitfield (1962). Radio-Electronic Transmission Fundamentals. New York, NY: McGraw Hill Book Company, Inc. pp. 243–244.
- ^Hall, Gerald (1988). The ARRL Antenna Book (15th ed.). American Radio Relay League. p. 24.25. ISBN0-87259-206-5.
- ^ abcdeHuggins, John S. 'J-Pole Antenna – Should I ground it?'. Retrieved 30 January 2012.
- ^ abcRichardson, Dan (March 1998). 'The J-Pole Revisited'(PDF). CQ Magazine: 34–41. Retrieved 30 January 2012.
- ^Fong, Edison (March 2007). 'The DBJ-2: A Portable VHF-UHF Roll-Up J-pole Antenna for Public Service'. QST. Newington, CT: ARRL, Inc.
- ^A folded-balun, sleeve balun, or common-mode choke will suppress feed-line RF currents. See: Straw, Dean (2007). '26 - Coupling the Line to the Antenna'. The ARRL Antenna Book. Newington, CT: The ARRL, Inc. ISBN0-87259-987-6.
- ^ abcHuggins, John S. 'Have your J-Pole and ground it too'. Retrieved 2015-03-04.
- ^Huggins, John S. 'Mast Mountable J-Pole Antenna'. Retrieved 2015-06-17.
- ^Huggins, John. 'Mast Mountable Antenna'. USPTO via Google. US Government. Retrieved 22 July 2017.
- ^US patent D798847, 'Antenna', issued 2017-10-03
- ^ abcJudd, Fred (1978). 'Slim Jim - 2 Metre Aerial'. Practical Wireless - Out of Thin Air: 37–39. Retrieved 24 April 2014.
- ^ abcdCebik, L. B. 'What is a Slim Jim?'. Cebik.Com. Archived from the original on April 24, 2014. Retrieved 30 January 2012.
- ^ abSteve Cerwin (2007). 'Mobile and Maritime Antennas - The Super-J Maritime Antenna'. In Straw, Dean (ed.). ARRL Antenna Book (21st ed.). The ARRL, Inc. pp. 16.23–16.26. ISBN0-87259-987-6.
- ^Franklin, Charles (1924). 'Franklin Antenna'(PDF). Retrieved 28 January 2016.
- ^Collins, Brian (1984). 'VHF and UHF Communication Antennas - Base-Station Antennas'. In Johnson, Richard; Henry Jasik (eds.). Antenna Engineering Handbook (2nd ed.). New York: McGraw-Hill. p. 27_14. ISBN0-07-032291-0.
- ^ abCebik, L. B. 'Some J-Poles That I Have Known Part 4: Some Things We Can and Cannot Do With a J-Pole'. Cebik.Com. Archived from the original on April 22, 2014. Retrieved 21 April 2014.
- ^ abcdeHuggins, John S. 'Improving the Super J-Pole Antenna'. Retrieved 21 April 2014.
- ^Huggins, John. 'Can a 2m J-Pole be used at 440?'. Hamradio.me. Retrieved 12 June 2019.
- ^ abcHuggins, John. 'Antenna radiator decoupling stub flub?'. Hamradio.me. Retrieved 12 June 2019.
- ^Huggins, John. 'Where quarter-wave radiator decoupling stubs work… and don't work'. Hamradio.me. Retrieved 12 June 2019.
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