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.
50 ohm coax to 75 ohm balanced output baluns are useful for low (< 1 wavelength) dipoles exhibiting 75 ohm characteristic impedance or for matching to balanced ladder line whose endpoint impedance is near 75 ohms.
50 ohm coax to 75 ohm CATV coax connections are easily done with a 1.5:1 unun with SO-239 connectors on input and output. Likewise 50 ohm coax to unbalanced verticals or loads near 75 ohms can be matched with a 1.5:1 unun.