RF Toroid Calculator by VK3CPU
50:600 ohm, (12:1) CUBE™ Balun/Unun, 1.8-31 MHz Balun/Unun, RX Only/1KW/2KW/3KW PEP, T2FD, Rhombic, End Fed, FlagpoleProduct DetailsCountry/Region of Manufacture: United StatesType: NewInput ohms/Output ohms: 50 in/600 out balanced (balun) or unbalunced (unun)Frequency Range < 2:1 SWR (MHz): 1.8-31PEP Power Rating (watts): RX only/1000/2000/3000Insertion Loss (dB): < .1 dBInput Connector: SO-239Hardware Type: Stainless SteelEnclosure Size: 4 x 4 x 2, 3KW = 4 X 4 x 4Weight (pounds): 2
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.
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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.