Availability
Baluns, Ununs and RF Chokes
DX Engineering Maxi-Core® 20 Baluns and Feedline Chokes
The present-day DX Engineering was launched in the year 2000. To celebrate our 20th Anniversary in the year 2020 we have developed a new line of Baluns and Feedline Chokes. Introducing DX Engineering "Maxi-Core® 20" Baluns and Feedline Chokes. They reduce or eliminate currents on the outside of your feedline allowing you to hear and to be heard much better. They keep more RFI/BCI out of your antenna and receiver and transfer more of your transmitted signal to the antenna for higher efficiency, the best antenna pattern and maximum performance. Signaling a new era of RF performance across the 1.8 to 54 MHz frequency range, DX Engineering Maxi-Core® 20 Baluns and Feedline Chokes handle full-legal-power-plus and provide higher common mode impedance (CMI) across a greater frequency range than competing models and even previous DX Engineering and Comtek models. Years of R&D coupled with major advancements in test equipment and techniques combined with custom ferrite materials have allowed our engineering team to design the DX Engineering Maxi-Core® 20 Baluns and Feedline Chokes. Maxi-Core® 20 Baluns and Chokes have high CMI across the AM Broadcast band and the HF/6M spectrum, which is essential to provide sufficient suppression of unwanted transmitted and received RFI/BCI current on the feedline shield exterior. Hear and be heard with DXE Maxi-Core® 20 Baluns and Feedline Chokes. Choose superior performance from these models: * DXE-MC20-1-1 Maxi-Core® 20 - 1:1 Current Choke Balun - For all HF-6m balanced antennas with a 50 ohm feedpoint, including resonant dipoles, loops, Yagis, beams, etc. * DXE-MC20-FC Maxi-Core® 20 - 1:1 Feedline Choke – This high CMI line isolator is perfect for use in line on 50 ohm coaxial feedlines, at the antenna, tower or shack end of the feedline. * DXE-MC20-1-1T Maxi-Core® 20 - 1:1 Current Choke Balun – This 1:1 "T" model is for force feeding antennas with a tuner. Use it at the end of ladder line of any impedance or mounted on a coax fed non-resonant antenna. This model tolerates operation at high SWR on non-resonant multi-band antennas. * DXE-MC20-C4-1 Maxi-Core® 20 - 4:1 Current Choke Balun is for use on antennas with a 200 ohm feedpoint and at the end of any impedance ladder line, especially on antenna systems with higher impedance. This model tolerates operation at high SWR on non-resonant multi-band antennas. * DXE-MC20-V4-1 Maxi-Core® 20 - 4:1 Voltage Balun is a 200 ohm to 50 ohm transformer for use on random long-wire and OCF antenna applications. This true voltage balun is intentionally designed with low CMI for antennas that need a transformer without RF choking for easier antenna tuner operation and it tolerates elevated SWR. Maxi-Core® 20 Baluns and Feedline Chokes are built into a convenient weather resistant NEMA enclosure that is mounted easily with optional brackets. They feature 1/4-20 stainless steel hardware and a high quality silver-plated PTFE dielectric SO-239 (UHF female) input connector. The SO-239 connector limits power handling to 5 kW at low SWR and reduced power at elevated SWR. These baluns and the feedline choke exhibit very low insertion loss and inherently low SWR. Optional mounting brackets are available for use on wire antennas or for verticals, Yagi and beam antennas. See the Suggested Parts tab after clicking "More Detail" on the model of interest. Combination packages that include balun or choke and mounting bracket are also available.
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$141.99
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$169.99
REZ Antenna Systems CM7 Common Mode Feedline Chokes
REZ Antenna Systems CM7 Common Mode Feedline Chokes are inline 1:1 common mode feedline chokes, consisting of seven mix-31 ferrite beads and RG223/U double shield coax. Proudly made in the USA, the compact and streamlined CM7 was designed to solve some of the most common issues that can negatively impact antenna system tuning and performance. For instance, common mode current carried on the outside of a coaxial cable can cause unwanted RF traveling back to your operating position, causing many issues. Another common issue is that the coax will become part of the antenna system and begin radiating RF. In most cases this is undesirable. Simply install the CM7 at the feed point of your antenna and attach your exiting coaxial cable to the opposite end. The CM7 can be used with many popular antenna types, such as EFHW, dipoles, random wires and verticals, to improve tuning consistency and antenna performance. Many antennas require the use of a 1:1 choke to isolate the coaxial cable from the antenna system for proper performance. Why not improve the performance of your antenna system? Order a REZ Antenna Systems CM7 Common Mode Choke from DX Engineering.
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$69.99
LDG Electronics RU-9:1 Unun
LDG Electronics RU-9:1 Unun was designed to allow easy interface of random length vertical and end fed antennas to the LDG line of Automatic Antenna Tuners. This 200 watt Unun also operates as a standalone, meaning that it does not necessarily require a tuner for use on a certain antenna. It may be used with many of your antenna projects where a 4:1 Unun is typically recommended. This model is small and easy to weatherproof for use in the elements. LDG RU-9:1 Unun specs: * Ratio: 9:1 * Frequency coverage: 1.8 to 30 MHz. * Power range: Up to 200 watts PEP * Enclosure dimensions (WHD): 2.5 x 5 x 1.25 in. * Weight: 6 oz.
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$39.99
LDG Electronics RU-1:1 Unun
LDG Electronics RU-1:1 Unun is intended to help remove unwanted RF from the coax cable shield. It is normally used as a common-mode RF choke for short coax cable runs or non-resonant antennas. The RU-1:1 features SO-239s for input and output. RU-1:1 Unun Specs: * Ratio: 1:1 * Frequency coverage: 1.8 to 30 MHz. * Power range: Up to 200 watts PEP * Enclosure dimensions (WHD): 2.5 x 5 x 1.25 in. * Weight: 6 oz.
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$39.99
LDG Electronics RU-4:1 200 Watt UNUNs
These LDG RU-4:1 200 Watt UNUNs were designed to allow for an easy interface of 43 ft., non-resonant vertical antennas to antenna tuners via 50-ohm coaxial cable. These 200 watt peak-power UNUNs also allow for the easy matching of resonant verticals--in many cases, without the use of an antenna tuner! They may also be used with many of your antenna projects where a 4:1 match is needed. When you are looking for an inexpensive solution to your antenna matching needs, these LDG RU-4:1 200 Watt UNUNs from DX Engineering are real matchmakers!
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$39.99
REZ Antenna Systems XFORM 4:1 UNUN
The REZ Antenna Systems XFORM 4:1 UNUN is a modular impedance-matching system designed for the Scout system, expanding its capabilities beyond traditional quarter-wave verticals and half-wave dipoles. It integrates seamlessly with the Scout XF base and supports legacy Scout bases via a jumper connection. The XFORM enables over 30 potential antenna deployment options when combined with future 9:1 and 49:1 transformer modules, which are currently in development. Built for durability, the XFORM features CNC-machined 6061 aluminum, an acetal polymer body, and stainless steel hardware. Its gasket-sealed design ensures reliable performance in harsh weather conditions. The unit handles up to 200 watts PEP SSB and 75 watts digital (50% duty cycle) and measures 5.5 inches in length with a maximum diameter of 2.5 inches. Each core is precisely wound and tested for thermal stability and minimal insertion loss, delivering efficient signal transfer and cooler operation underload. The XFORM requires a Scout base for use, making it an essential upgrade for operators seeking maximum versatility and performance in portable HF antenna systems.
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$189.95
LDG Electronics 1:1 Current Baluns
LDG Electronics 1:1 Current Baluns were designed to allow for the easy interface of ladder line antennas and long wires with the LDG line of automatic antenna tuners. * Configuration: 1:1 Current Balun * Frequency Coverage: 1.8 to 30 MHz. * Power Range: 100W continuous or 200 watts PEP * Easy to weatherproof * Enclosure size: 5 x 2.5 x 1.25 in. * Weight: 6 oz. (including enclosure) These baluns operate "stand alone"; thus, they do not require an LDG tuner. They may be used with any of your longwire, random wire, or ladder line antenna projects. For low power operation it's hard to beat the value in LDG Electronics 1:1 Current Baluns from DX Engineering!
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$39.99
COMTEK CFC-50X Common Mode Feedline Chokes
COMTEK CFC-50X Common Mode Feedline Chokes are designed to suppress unwanted RF currents on the outside of the shield on coaxial feedlines. These 1:1 inline coaxial feedline chokes are built with fifteen Mix-31 ferrite beads on premium DX Engineering RG-8X coaxial cable, offering improved performance for a wide variety of antenna systems. COM-CFC-50X Key Benefits: • Provides Effective Shield RF Current Suppression from 1.8 to 54 MHz, helping eliminate common mode currents that cause RF feedback and noise inside the feedline. • Consistent and balanced pattern across frequency range: Excellent RF choking isolating the feedpoint prevents current imbalance, which preserves radiation pattern and antenna performance.
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$59.99
COMTEK Current Feedline Chokes
The updated COMTEK CFC-50A 50 ohm Feedline Chokes consist of 75 heavy-duty mix-31 RF choke beads on a length of RG400 PTFE coax terminated at both ends with silver-plated PTFE PL-259/UHF male connectors and the correct length of heat-shrink tubing. COMTEK Current Feedline Chokes ensure that stray RF does not flow on the outside shield of your feedlines. They are typically installed at the antenna feedpoint connection. They may also be used where a long run of feedline leaves a remote antenna switch or a tower. They are also very effective at the shack end of a long run of on-the-ground or above-ground coaxial feedline, to block unwanted RF signals and noise picked up on the shield. These chokes provide excellent common mode impedance and handle up to 5 kW from 1.8 to 54 MHz. These chokes are assembled except for the tubing needs to be installed and heat-shrinked after the choke is positioned as it will be installed.
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$131.49
LDG Electronics 4:1 Voltage Baluns
LDG Electronics 4:1 voltage baluns were designed to allow for the easy interface of ladder line antennas and long wires with the LDG line of automatic antenna tuners. * Configuration: 4:1 Voltage Balun * Frequency Coverage: 1.8 to 30 MHz * Power Range: 100 W continuous or 200 watts PEP * Easy to weatherproof * Enclosure size: 5 x 2.5 x 1.25 in. * Weight: 6 oz. (enclosure weight included) These baluns operate "stand alone"; thus, they do not require an LDG tuner. They may be used with any of your long, random, or ladder line or other antenna projects.
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$39.99
DX Engineering Maxi-Core® High-Power Multi-Band UNUNs
DX Engineering High-Power Multi-Band UNUNs with Maxi-Core® technology allow your antenna to perform to its fullest potential and reduce stress on your equipment. These specially tuned UNUNs, designed for non-resonant vertical antenna applications, operate more efficiently than similar competitive products. Lesser products may burn up easily on lower bands with QRO power levels. DX Engineering high-power UNUNs are specifically designed for applications with 43 ft. non-resonant, multi-band antennas, ensuring the best efficiency from your antenna and transmission line/tuner installation. The results are minimizing the additional transmission line losses caused by abnormally-high SWR. DX Engineering Maxi-Core® High-Power Multi-Band UNUNs can be added to any existing 43 ft. antenna installation or used to replace an older competitive UNUN for a performance increase. The UN-43-R includes mounting bracket and feed-point connections braids. Note: Whenever the DX Engineering "Documentation" tab is available, please look at the associated files for additional product information. All non-resonant vertical antennas present high SWR to their feed lines. Deal with it! Order DX Engineering High-Power Multi-Band UNUNs!
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$201.99
DX Engineering LPFC-BNC Low Power Feedline Chokes
DX Engineering LPFC-BNC Low Power Feedline Chokes are intended to be placed in line with coaxial cable fed antennas and equipment used for portable operations, including POTA and SOTA activations. The DXE-LPFC-BNC coax wound toroid achieves an amazing common mode impedance (CMI) curve, with an RF choking capability that far exceeds the CMI of 'a-few-beads-on-coax' product that is offered by other suppliers. Actually, these "Low Power" Feedline Chokes can be used in any station that runs less than 250 watts SSB, 100 watts CW or Digital. ________________________________________ DX Engineering Low Power Feedline Chokes features and benefits: - A unique, lightweight form, with clear heat shrink over the choke* - Light enough to hang inline at the feedpoint of any portable HF antenna. - BNC female connectors for easy connection to portable antennas and gear. - Much higher CMI that other portable, low power chokes, especially across the 40 through 6 meter bands. - Frequency range of 1.8 through 54MHz. - RF Power Handling up to 250 watts PEP SSB, 100 watts CW and Digital (at SWR <2:1). - Recommended for general use to isolate either end of a coaxial cable. * Not intended for permanent outdoor use unless mounted inside a weatherproof enclosure. ________________________________________ These chokes are ideal for use at any HF transceiver or receiver antenna connection, portable, mobile or base. In most cases, DXE-LPFC-BNC prevents RFI, stops stray RF and noise on the feedline from getting into the receiver that would cover up weak signals, and improves efficiency of the antenna system. For any station, including POTA and SOTA, mobile and base, DX Engineering Low Power Feedline Chokes keep the RF controlled.
Not Yet Reviewed
$59.99
DX Engineering Maxi-Core® 20 Feedline Choke and Mount Kits
DX Engineering Maxi-Core® 20 Feedline Choke and Mount Kits, DXE-MC20-FCM, provide current balance and feedline isolation on coaxial cables for all types of HF through 6 meter antennas including verticals, rotatable dipoles, directional beams and Yagi antennas. Intended for 50 ohm feedlines operated at low SWR, this combination of mounting plate bracket and effective 50 ohm RF choke handles full-legal-power-plus and provides higher common mode impedance (CMI) across a greater frequency range than competing feedline choke and line isolators and previous DX Engineering and Comtek models. High CMI across the AM Broadcast band and the HF/6M spectrum is essential to provide sufficient suppression of unwanted transmitted and received RFI/BCI current on the feedline shield exterior. With less noise and interference you will hear and be heard using a DX Engineering Maxi-Core® 20 Feedline Choke and Mount Kits. DX Engineering Maxi-Core® 20 Feedline Choke and Mount Kits bring new parts together to work on many types of antennas. They provide improved RF isolation and current balance at either end of the feedline and at the feedpoint of a vertical, a beam, rotatable dipole or other antenna feedline. This is a unique perpendicular choke mount that allows a beneficial separation between the ferrite of the choke and the antenna boom or mast, resulting in improved choking performance compared to a choke mounted on metal. The UV black high-strength polymer mounting plate provides additional isolation and holes for different mounting positions for the choke, horizontal or vertical. Stainless steel hardware is included to attach the plate to the stainless steel mounting bracket, which has laser cut holes for one of five optional DX Engineering Saddle Clamps to cover mast or boom sizes from 1 to 2 in. and 2.375 to 3 in. Click "More Detail" for additional information and click Suggested Parts for required optional items including one saddle clamp to fit your mast or boom and coaxial cable assemblies. Maxi-Core® 20 Feedline Chokes features high quality silver-plated PTFE dielectric SO-239 (UHF female) connectors. The SO-239 connector limits power handling to 5 kW or less at low SWR and reduced power at elevated SWR. These feedline chokes exhibit very low insertion loss and inherently low SWR. They are built into a convenient weather resistant NEMA enclosure with weep holes at all four corners of the "bottom" side of the enclosure, to vent properly when mounted vertically or horizontally for all types of antennas. Make your antenna play to its potential; reduce RFI and improve reception with DX Engineering Maxi-Core® 20 Feedline Choke and Mount Kits.
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$207.98
DX Engineering Wire Antenna Balun Mounting Brackets
DX Engineering Wire Antenna Balun Mounting Bracket Kits are custom designed specifically for mounting high-performance Maxi-Core® 20 Baluns or legacy Comtek baluns. These kits include the virtually unbreakable combination balun mounting frame and wire antenna center insulator bracket, two DX Engineering End Insulators plus all stainless steel hardware. This unique design provides minimum capacitive coupling between the antenna wire and the field surrounding the balun core. Wire Antenna Balun Mounting Bracket Kits are the ideal starting point for building a top-performing and long-lasting coaxial cable fed single-band or multi-band wire antennas. Use a DX Engineering Maxi-Core® 20 Balun or Comtek balun, or other manufacturer's similar NEMA box balun, for a resonant or off-center fed dipole, inverted-V or loop. Use the optional coaxial cable strain relief (DXE-CSR213-1 for RG-213 or RG-8U sized coax or the DXE-CSR8X-1 for RG-8X sized coax) with your optional dipole wire (DXE-ANTW Antenna Wire) and antenna rope, all from DX Engineering. These patented** balun wire antenna insulator brackets and end insulators are made from a super high-strength UV resistant black poly-resin compound. They provide an exclusive serpentine wire-weave grip for insulated antenna wire. This method of threading the wire provides a grip strong enough to permanently support the antenna wires without the need for soldered wrapped wire ends onto the antenna wires. This allows fast and easy field adjustments of antenna length for tuning without soldering. Get everything you need to build the best performing, longest lasting wire antenna possible, all from DX Engineering! DX Engineering Wire Antenna Balun Mounting Bracket Kits DXE-WA-BMB: 1 ea. Balun & Wire Antenna bracket High-strength UV black poly-resin (** US Patent # D744,459) 2 ea. DX Engineering End Insulators High-strength, UV poly-resin (**US Patent # D534,905) 4 ea. 6-32 x 3/4" long Stainless Steel Hex Head Bolts 8 ea. #6 Stainless Steel Flat Washers 4 ea. 6-32 Nyloc Hex Nuts Click "More Detail" to see the "Documentation" tab for additional product information and the "Suggested Parts" tab for the additional items (not supplied) for your resonant wire antenna project with the DX Engineering Wire Antenna Balun Mounting Bracket Kit.
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$29.99
Comet Antennas HF/6M RFI Chokes
Comet Antennas HF/6M RFI Chokes are designed to be easy to install and will help prevent or reduce RFI carried into the shack by the coax. The TRF-Mini features a PL-259 connector on one end and an SO-239 on the other, this cable assembly includes a ferrite core at the center. At just 7 inches long, there is sure to be room behind your radio for this choke that can handle up to 350 watts and covers from 1.8-54 MHz.
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$29.95
Chameleon Antenna Baluns UNUNs and Chokes
Chameleon Antenna Baluns UNUNs and Chokes are available in a variety of ratios that include 1:1, 4:1, 6:1 and 9:1 and they are compatible with an array of antennas and systems. These Baluns and UNUNs will enhance impedance transformation and signal efficiency while minimizing unwanted interference. The FT240-43 toroidal cores are precisely wound with PTFE-insulated, 14AWG enameled copper wire and assembled in a durable, weatherproof housing that's suitable for even the most adverse weather conditions. The top mounted stainless steel eyebolt provides a secure anchor point for base or portable operation.
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$115.00
DX Engineering Ferrite Bead Choke Kits
DX Engineering Ferrite Bead Choke Kits, DXE-FBC, provide the components for the simplest and most effective technique of creating RF isolation at an antenna feedpoint or feedline termination. Covering the frequency range 1.8 to 54 MHz, these 40 toroidal mix-31 solid ferrite beads, installed on a user supplied coaxial cable (prior to connector installation*), to build an RF choke with a very high Common Mode Impedance (CMI) over a very wide frequency range. This is the same choke that world-class contest and DX stations install. Given the simplicity and raw performance of this 40-bead choke, its comprehensive RF features and benefits should become familiar to every radio amateur and antenna experimenters. * Yes!, the superior overall performance of the DXE-FBC Ferrite Bead Choke completely offsets the trouble of cutting off a coaxial connector, installing the kit, and then installing a new connector. It really is that good!
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$152.99
DX Engineering Maxi-Core® 20 1:1 Balun and Mount Kits
DX Engineering Maxi-Core® 20 1:1 Balun and Mount Kits, DXE-MC20-1-1BM, provide current balance and feedline isolation for HF through 6 meter verticals, rotatable dipoles, directional beams and Yagi antennas. Intended for 50 ohm feedpoint antennas that offer low SWR, this combination of mounting plate bracket and effective 1:1 RF choke balun handles full-legal-power-plus and provides higher common mode impedance (CMI) across a greater frequency range than competing balun models and previous DX Engineering and Comtek models. Their high CMI across the AM Broadcast band and the HF/6M spectrum is essential to provide sufficient suppression of unwanted transmitted and received RFI/BCI current on the feedline shield exterior. With less noise and interference you will hear and be heard using a DX Engineering Maxi-Core® 20 1:1 Balun and Mount Kit. A similar kit was formerly known as the Vertical Feedline Current Choke. But, the Maxi-Core® 20 1:1 Balun and Mount Kit bring new parts together to work on many types of antennas. They provide improved RF isolation of the feedline and current balance at the feedpoint of a vertical, a beam or rotatable dipole. This is a unique perpendicular mount that allows a beneficial separation between the ferrite of the balun and the antenna boom or mast, resulting in improved choking performance compared to a balun mounted on metal. The UV black high-strength polymer mounting plate provides additional isolation and holes for different mounting positions for the balun, horizontal or vertical. Stainless steel hardware is included to attach the plate to the stainless steel mounting bracket, which has laser cut holes for one of five optional DX Engineering Saddle Clamps to cover mast or boom sizes from 1 to 2 in. and 2.375 to 3 in. Maxi-Core® 20 Baluns feature 1/4-20 stainless steel hardware and a high quality silver-plated PTFE dielectric SO-239 (UHF female) input connector. The SO-239 connector limits power handling to 5 kW or less at low SWR and reduced power at elevated SWR. These baluns exhibit very low insertion loss and inherently low SWR. Maxi-Core ® 20 Baluns are built into a convenient weather resistant NEMA enclosure with weep holes at all four corners of the "bottom" side of the enclosure, to vent properly when mounted vertically or horizontally for all types of antennas. Click "More Detail" for additional information and click Suggested Parts for optional items required, including one saddle clamp to fit your mast or boom, and a wiring kit or flexible copper strap to connect the balun to the antenna feedpoint terminals. Make your antenna play to its potential; reduce RFI and improve reception with DX Engineering Maxi-Core® 20 1:1 Balun and Mount Kits.
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$207.98
DX Engineering Balun or Choke Mounting Plate and Bracket Kits
DX Engineering Balun or Feedline Choke Mounting Plate and Bracket Kits provide a variety of mounting solutions for DX Engineering Maxi-Core® 20, Comtek and other brands that use 4 x 4 x 2 in. plastic NEMA boxes. This rugged polymer plastic plate and stainless steel bracket kit may be used at the base of any vertical, on the boom of a Yagi or beam antenna, or even on a mast or post. This unique perpendicular mount provides a beneficial separation between the ferrite of the balun or choke and the metal tubing of the antenna or mount, resulting in improved choking performance. This UV black high-strength polymer mounting plate provides additional isolation between the feedline and the antenna system for optimal performance and decoupling. The stainless steel mounting bracket has holes laser cut for any one of these optional heavy-duty DX Engineering V-Saddle Clamps. Choose based on the outside diameter (OD) of your antenna mounting pipe or boom tubing: -DXE-CAVS-11P for 1/2 to 1-3/4 in. aluminum tubing -DXE-CAVS-2P for 1 to 2 in. aluminum tubing -DXE-CAVS-3P for 2 to 3 in aluminum tubing -DXE-SSVC-2P for 1 to 2 in. for steel pipe -DXE-SSVC-3P for 2.375 to 3 in. steel pipe No optional clamps are necessary when attaching this Mounting Plate and Bracket Kit to a 4x4 or 6x6 wooden post for vertical. Use two suitable wood lag bolts or carriage bolts from a local hardware. DX Engineering Balun or Feedline Choke Mounting Plate and Bracket Kits are the right choice to mount a DX Engineering Maxi-Core® 20 Balun or Feedline Choke onto a vertical or beam antenna.
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$37.99
PackTenna Mini In-Line RF Feedline Chokes
PackTenna Mini In-Line RF Feedline Chokes are designed to suppress RF interference caused by common mode current flowing from the antenna feed point back to the radio. This type of current can disrupt radio performance and affect nearby equipment. In-line chokes are recommended for all end-fed antennas when operating above 20 watts. While you may not experience issues immediately, RF interference can occur as you increase power, change bands, adjust coax length, or reposition the antenna.
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$75.00
OptiBeam Baluns
OptiBeam Baluns are built with high-grade components for excellent performance. These baluns are supplied as original equipment on OptiBeam Yagi and Rotatable Dipole antennas. They provide a high level of isolation between the antenna and feedline to maintain a balanced pattern and consistent operational results. OptiBeam Baluns are available for use as a replacement on OptiBeam Yagi and Rotatable Dipole antennas. Two models are available: the 50 ohm to 50 ohm (1:1) is for the majority of antennas. The special 25 ohm to 50 ohm (1:2) is only for antennas specifically designed with a 25-ohm feedpoint. Be certain to order the correct ratio to match your antenna. Both models cover 3.5 to 60 MHz. Each OptiBeam Balun includes the connection L-brackets for direct mounting of the balun stand-off to the antenna feedpoint studs. At the other end, a standard SO-239 (UHF female) connector accepts the coaxial cable mounted PL-259 (UHF male) connector. OptiBeam Baluns are rated to 6 kW PEP on tuned Yagi and Rotatable Dipole antennas with typical low SWR. For replacement on your OptiBeam antennas, OptiBeam Baluns are ready to upgrade your antennas.
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$207.99
InnovAntennas Ferrite Bead Baluns
InnovAntennas Ferrite Bead Baluns are fully assembled and ready to install, to achieve the absolute best performance from an InnovAntennas Yagi or other balanced terminal antennas. In contrast to wound baluns, ferrite bead choke baluns have the advantage of covering a wide frequency range for multiple bands. As required for most Yagi antennas from InnovAntennas with 50 ohm direct feed, ring terminals are installed on one end for the studded feedpoint connection. The other end is terminated in either Type-N or SO-239/UHF Female for the appropriate band coverage and impedance. Heat shrink filled with a UV-resistant adhesive provides a waterproof cover over the ferrite beads on the cable and the connector. Why do I need a Balun on my Yagi? Ferrite Bead Baluns offered by InnovAntennas provide very important functions of a balun, which is not well understood. For proper antenna performance, a ferrite bead balun inhibits common-mode current two important ways; A) it prevents RF flow on the outside the coax shield cable when transmitting, and B) it prevents stray RF noise picked up by the coax cable shield from entering the antenna system and affecting the receiver. What happens on the antenna without a RF choke balun? Several problems can occur. When an unbalanced feedline is connected directly to a balanced antenna with no BALUN in place, common-mode currents will run on the outside of the coaxial cable shield. The Yagi feedpoint is forced out of balance causing a skew and diminished beam antenna pattern and gain. A loss of Front-to-Back ratio (F/B) can occur, as well as detuning that affects antenna frequency, potentially causing increased SWR. In addition to the pattern distorting performance drop, radiation from the antenna feedline can cause interference to home and business electronics. The other very important benefit of using a wideband ferrite bead balun is to reduce received noise in certain situations. While the noise produced by many household products is normally at very low levels, sensitive ham radio receivers can be affected, which can prevents weak signals being heard. RF noise picked up on the coax cable shield will enter the antenna system feedpoint when no ferrite bead choke balun is installed at the feedpoint.
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$108.99
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$119.99
DX Engineering TWIG QRP 9:1 UNUNs
The DXE-TWIG-9-1 QRP UNUN (Unbalanced-to-Unbalanced transformer) matches a high-impedance, non-resonant end-fed/random wire antenna (33 to 84 feet long) to the 50-ohm unbalanced load required by amateur radio transceivers. The DXE TWIG-9-1 covers 1.8–30 MHz and is ideal for portable (QRP) or HOA-restricted antennas. The connector on the DXE-TWIG-9-1 is a BNC female to mate with the recommended 35 to 50 feet of coax cable, which is used as the counterpoise. In some cases, an external wide range tuner may be needed. This UNUN may not provide a perfect 1:1 SWR on all bands without an additional tuner and may experience heating at higher power due to impedance mismatches. Typically, 9:1 UNUNs are used for: • Random Wire Antenna: Long wires of specific non-resonant lengths (e.g., 29, 35.5, 41, or 71 feet) designed to avoid an electrical half-wave, or multiple of a half-wave, on any amateur band. • End-Fed Long Wire: General-purpose long wire used for wideband receiving or multiband transmitting where an antenna tuner is available. • Inverted "L" or Sloper Configuration: When these are fed as non-resonant wires rather than resonant half-wave radiators. Tips on How to Use the 9:1 QRP UNUN as a Random Wire Antenna 1. Select a "Random" Length: Do not use resonant half-wave lengths. Popular lengths that avoid resonance on amateur bands include e.g., 29, 35.5, 41, or 71 feet. 2. Connect the Antenna Wire: Attach your long wire to the element wire terminal of the UNUN. 3. Use an Antenna Tuner: Because a random wire is never perfectly resonant, you may have to use an internal or external antenna tuner to achieve a low SWR for your transceiver. 4. Placement: Mount the UNUN near the ground or on a short support and run the element wire as high and clear of obstacles as possible. The antenna shown in this manual was tested using the optional 24 or 26 AWG wire such as CEW-VIZ24-YEL100 stranded copper, PVC insulated, high visibility yellow antenna wire. The coax cable (with BNC connectors) is recommended to be 35 to 50 feet in length since the coaxial cable shield is used as the counterpoise. The antenna can be installed in different configurations. Wire lengths will vary depending on the installation and antenna design chosen. This is a low power (QRP) antenna system impedance matching UNUN which handles 25 Watts on SSB, 10 Watts on CW and 5 Watts on digital mode when the antenna SWR is less than 2:1 without the use of an antenna tuner.
Not Yet Reviewed
$49.99
DX Engineering Balun Upgrade Kits
DX Engineering Balun Upgrade Kits provide the superior performance of a 1:1 DX Engineering Maxi-Core® 20 Balun, mounting bracket, hardware and clamps for your antenna update. Maxi-Core® 20 Baluns keep more RFI/BCI out of your antenna and receiver and transfer more of your transmitted signal to the antenna for higher efficiency, the best antenna pattern and maximum performance. They handle full-legal-power-plus and provide higher common mode impedance (CMI) across a greater frequency range than competing models and previous DX Engineering and Comtek balun models. DX Engineering Balun Upgrade Kits include: - DXE-MC20-1-1 Maxi-Core® 20 - 1:1 Current Choke Balun - For all HF-6m balanced antennas with a 50 ohm feedpoint, including resonant dipoles, loops, Yagis and beams. - DXE-BMB-4P Balun Mounting Bracket, For Maxi-Core® 20, with Poly-Resin Plate and Stainless Steel Hardware - DXE-BALUN-WK DX Engineering Balun Wiring Kits - Wire, Terminal and Hardware for antenna connection - DXE-ECLS-150 or DXE-ECLS-200 Stainless Mounting Clamps with Studs – One pair of studded band clamps with Stainless Steel Hardware, for antennas with 1.50 in. boom or mast or up to a 2.00 in. boom or mast. Maxi-Core® 20 Baluns and Feedline Chokes are built into a convenient weather resistant NEMA enclosure that is mounted easily with optional brackets. They feature 1/4-20 stainless steel hardware and a high quality silver-plated PTFE dielectric SO-239 (UHF female) input connector. They have weep holes at all four corners of the "bottom" side of the enclosure, so they work properly for vertical or horizontal mounting for all types of antennas. The SO-239 connector limits power handling to 5 kW at low SWR and reduced power at elevated SWR. These baluns exhibit very low insertion loss and inherently low SWR. When it is time to refurbish your Yagi, beam or rotatable dipole, purchase DX Engineering Balun Upgrade Kits to use the best 1:1 baluns for your antennas.
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$226.96
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$227.96