1:1 Current Balun Kit (1000-Watt PEP, 160-6 Meters)
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/250 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. Common mode impedance peaks around 3,500 ohms at 10 mhz.
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.
The kit consists of a F140 ferrite toroidal core, enamel insulated wire, a So239 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.
Model BA-1-1000…………$14.95 (160-6 meters)
1:1 Current Balun Kit (1500-Watt PEP, 160-6 Meters)
BA-1-1500 160-6 meter 1:1 Current Balun (shown assembled)
Model BA-1-1500 is a 1:1 balun kit used to translate a 50 ohm unbalanced input to 50 ohms unbalanced at power levels up to 1500 watts PEP when used with a matched load. With a matched load the SWR will not exceed 1.5 over the frequency range 1.8 to 30 MHz. 1,500 PEP watt rating on a 25% duty cycle.
The kit consists of a F240 ferrite core, two colors of 1000 volt insulated wire. two SO-239 connectors (one for input and one for output connections) with stainless steel hardware, and an illustrated instruction manual with directions to assemble the kit as a 1 to 1 balun (unbalanced coax to balanced antenna/load) or unun (unbalanced to unbalanced). Leave one of the SO-239 connectors off on the output side and connect to your balanced antenna (dipole, beam driven elements, etc). To use as a line isolator/common mode choke, use both SO-239 connectors and insert in series with the coax feed line. For best results use one at the antenna and one for the rig side at the antenna tuner. The number of turns on the toroid can be changed to emphasize the low, mid or high portion of the 160-10 meter bands range as well as the choking impedance (see graph below). Assembly time is about 30 minutes. You can vary the number of turns to emphasize different frequency ranges.
BA-1-1500 Choking Z magnitude – 14 Turns and 10 Turns
Just add your custom enclosure, or optional enclosure box below, with the kit and you have a compete 1:1 current balun/unun.
Model BA-1-1500…………$24.50 (160-6 meters, 1K-6K choking impedance)
Enclosure Boxes – click HERE
Balun Enclosure Box with SO-239 shown installed. Box is delivered without holes drilled.