Multi Ratio 2.25:1/4:1/9:1/16:1 CUBE™ Unun, 3-31 MHz, 1.2KW Watt, vertical, end fed
Model CU-2-4-9-16-1200 is a 2.25:1, 4:1, 9:1 and 16:1 unun housed in a NEMA enclosure box (4" x 4" x 2") with one stud for 2.25:1 (112.5 ohms), one stud for 4:1 (200 ohm load), one stud for 9:1 (450 ohm load) and another stud for 16:1 (800 ohm load) outputs, each capable of input power levels up to 1200 watts PEP when used with a matched load. (You can only have 1 load connected).
A great multi-purpose unun for 31 or 43 foot fiberglass verticals, end fed non-resonant antennas, traveling wave verticals, etc. Quad core, Ruthroff style unun with side ground terminal for adding a counterpoise or radials as an option. Now you don’t need to buy three separate ununs – just buy the CU-2.25:1-4-9-1200 and pick the output ratio that provides the best match for your antenna tuner!
Impedance transformations from 1-30 Mhz are shown below:
The Unun provides multiple taps for impedance conversions of:
- 50 to 450 (9:1) – for end fed long wires, traveling wave antennas
- 50 to 200 (4:1) – for ¼ wave vertical folded dipoles, OCF verticals