5:1 Baluns/Ununs

5:1 CUBE™ Unun – Model CU-5-1500 (50:250 Ohm, 1.8-61 MHz, 1.5KW PEP)

Application. For traveling wave, end fed or portable 20-31 foot vertical antennas the 5:1 unun makes a good transformer for converting 50 ohm coax to a 250 ohm feed point. If you use the antenna on multiple bands, the feed point impedance may not always be 250 ohms and use of the unun at high (>350 ohms) or low (<100 ohms) will require reduced power input or the unun may have its power ratings exceeded and damage to the unun may occur. The (5:1 conversion ratio will change for loads other than 250 ohms unbalanced.

Typical application:

CU-5-1500 antenna

Also available as a balanced output – CB-5-1500

50:250 ohm (5:1) CUBE™ Balun. 1.8-61 MHz, 1500 Watts

CB-5-1500

50:250 ohm (5:1) CUBE™ Balun. 1.8-61 MHz, 1500 Watts CB-5-1500

Model CB-5-1500TS- 5 to 1 Balanced Output Balun

(SO-239 in with output connectors on top similar to CB-2-2000 balun shown in picture)

Purpose. This balun is designed to match 250 ohms balanced to 50 ohms unbalanced up to 1500 watts PEP power from 1.8-61 MHz. It provides conversion from unbalanced 50 ohm coax to a balanced 250 ohm load/antenna feed point and gives a 5:1 impedance step-up to reduce VSWR on the coax feed line. The balun is housed in a 4” x 4” X “2 NEMA weather resistant box with SO-239 coaxial input and a ¼” stud terminals with wing nut on the top for output

This balun is DC grounded and will bleed off static electricity but it is NOT A LIGHTNING ARRESTOR.


Application. For use on Bruce Arrays and similar antennas with balanced 250 ohm feed point requirements.


Use a coax noise filter to reduce noise from any antenna or a line isolator to electrically isolate the coax braid from becoming part of the antenna.

$79.95 In stock
Brand:Palomar Engineers
MPN:CB-5-1500
input ohms/output ohms::50 in / 250 output
Frequency Range (MHz):1-31
PEP Power Rating (watts)::1500