HF 12:1 Impedance Transformers
12:1 Baluns are useful transformers for 600 ohm balanced loads the impedance at the end of the feed line is 600 ohms (1/2 wavelength feed line), or high impedance feeds for rhombic, T2FD and traveling wave antennas.
12:1 Ununs are useful between coax and long wires with a load impedance near 600 ohms like a beverage antenna. Shortwave listener antennas also can benefit with the 12:1 unun and it may provide a better match than 9:1 ununs – this means quieter noise levels and stronger signals so you can hear distance stations easier.
For end fed antennas, use a 9:1 unun or 12:1 unun - also available in the "Bullet" antenna end fed style (Bullet-12U-500)
Receive only baluns/ununs are rated for 100 watts PEP
All enclosure boxes have 2 side flanges with 1/4" holes.
All of these products are made to order and typical production time is 10 days depending on quantity.
We specify impedance ratios as an output to input ratio where the output (or load) is given first and the input is given second (e.g. 100:50 (2:1) would mean a 100 ohm output and a 50 ohm input; a 25:50 (1:2) would mean a 25 ohm load and a 50 ohm input). Most all products use a 50 ohm input unless otherwise specified.
We have products that are available as kits for the do-it-yourself (DIY) person or fully assembled and tested units for the “Plug & Play” crowd.
Our impedance transformers are available using two different topologies: Binocular cores or toroid cores with multiple turns for increased effectiveness and wide band frequency transformations. We utilize single and multiple core transformers using high order windings when needed to extend product performance.
We rate the power ratings as watts PEP (Peak Envelop Power) with standard duty cycles for various modes. To determine the PEP rating required for your needs, see: Choke & Transformer Power Ratings
This website page serves as a link page to the frequency ranges of our impedance transformers configured as either baluns or ununs. You can click on a picture to go to the specific page about the products described in the picture.