1:1 Current BalunProduct DetailsModel BA-1-1000 is a 1:1 balun kit used to translate a 50 ohm
unbalanced input to 50 ohms unbalanced at power levels up to 1000 watts
PEP/100 watts continuous when used with a matched load. With a matched
load the SWR will not exceed 1.5 over the frequency range 1.8 to 61 MHz.
1,000 PEP watt rating on a 25% duty cycle. Will sustain about 100 watts RTTY or FT8 at 6 meters. (for higher power use the BA-1-1500 with 6-8 turns for higher frequencies).
Common mode impedance peaks
around 3,500 ohms at 10Mmhz.
With a matched 50 ohm load the SWR over the frequency range 1.8 to 61
MHz is shown in the following table measured with an AIM 4170 network
analyzer. Notice that the conversion from 50 to 50 ohms is very
consistent from 1.8-61 MHz and SWR is less than 1.3:1 over the range
allowing easy tuning by most radio internal antenna tuners or an
external tuner.
Ba-1-1000 1:1 Balun/Unun 1KW PEP 1-61 Mhz
The kit consists of a F140 ferrite toroidal core, enamel insulated
wire, a SO-239 connector with stainless steel hardware, and an
illustrated instruction manual with directions to connect the kit as a 1
to 1 balun/unun (unbalanced coax to unbalanced antenna or balanced
antenna like a dipole). Balun assembly time takes about an hour and is a
fun learning process.
Add a SO-239 Kit on output side to create a 1:1 unun (coax to coax line isolator) or add studs for a balun for use with dipole or beam antenna.
Use the recommwnded CB-Box-1 for a convenient enclosure.
HF 1-61 MHz coax feed line common mode chokes
Model BA-1-1000 is a 1:1 balun kit used to translate a 50 ohm
unbalanced input to 50 ohms unbalanced at power levels up to 1000 watts
PEP/100 watts continuous when used with a matched load. With a matched
load the SWR will not exceed 1.5 over the frequency range 1.8 to 61 MHz.
1,000 PEP watt rating on a 25% duty cycle. Will sustain about 100 watts RTTY or FT8 at 6 meters. (for higher power use the BA-1-1500 with 6-8 turns for higher frequencies).
Common mode impedance peaks
around 3,500 ohms at 10Mmhz.
With a matched 50 ohm load the SWR over the frequency range 1.8 to 61
MHz is shown in the following table measured with an AIM 4170 network
analyzer. Notice that the conversion from 50 to 50 ohms is very
consistent from 1.8-61 MHz and SWR is less than 1.3:1 over the range
allowing easy tuning by most radio internal antenna tuners or an
external tuner.
Ba-1-1000 1:1 Balun/Unun 1KW PEP 1-61 Mhz
The kit consists of a F140 ferrite toroidal core, enamel insulated
wire, a SO-239 connector with stainless steel hardware, and an
illustrated instruction manual with directions to connect the kit as a 1
to 1 balun/unun (unbalanced coax to unbalanced antenna or balanced
antenna like a dipole). Balun assembly time takes about an hour and is a
fun learning process.
Add a SO-239 Kit on output side to create a 1:1 unun (coax to coax line isolator) or add studs for a balun for use with dipole or beam antenna.
Use the recommwnded CB-Box-1 for a convenient enclosure.
1:1 feed line Chokes (also known as feed line current chokes, common mode chokes, line isolators, current mode chokes, and 1:1 baluns/ununs) are available in kit form or assembled form in a weatherproof Current Unun and Balun Enclosure which we call a CUBE™. All 1:1 chokes are ferrite based and are designed for 50 ohm coaxial cable input and 50 ohm output. 1:1 Ferrite toroidal or bead chokes have a higher choking impedance than our popular Sleeve Chokes and various models are available for specific frequency ranges and power levels.
1:1 Chokes are useful for choking common mode currents that may flow on the exterior of the coax cable shield while allowing the signals on the interior of the shield and the center conductor to flow unaffected and keeping the common mode current on the antenna. They isolate the coax shield and prevent it from becoming part of the antenna system.
1:1 Chokes are useful between balanced lines for center fed dipoles at their fundamental frequency (468/f (MHz), beam antennas with a 50 ohm balanced driven element, G5RV, loops, yagis, NVIS antennas, mobile installations, portable antennas and anywhere common mode current (or RFI) is a problem. They are also helpful between transmitter and linear amplifier or between linear amp and antenna tuner or as isolation chokes where higher choking impedance is needed (in the range of 2K-7K ohms).
1:1 Chokes are also very useful as feed line current chokes at the “radio end” of the antenna (we call them coax noise filters) where they choke/filter common mode current induced onto the coax shield from radiated waves (from your antenna, and other sources such as DSL routers, computer devices, plasma TVs, etc. originating in your house or your neighbor’s house). For RFI issues see RFI/EMI Solutions for general use or for specific radios and devices.
For best results we recommend a 1:1 choke at the “antenna end” of the coax and a coax noise filter at the “radio end” of the coax. (A side benefit is a reduction in noise level caused by common mode currents). 1:1 chokes are also available as Sleeve Chokes (Slip on or Snap on) for ease of installation and light weight on the antenna.