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50:450 ohm (9:1) CUBE™ Unun, 1.8-31 MHz, 5 KW PEP, End Fed AntennaProduct DetailsInput ohms/Output ohms: 50 in / 450 outFrequency Range < 2:1 SWR (MHz): 1-31 MHzPEP Power Rating (watts): 7500Model CU-9-5000 is a 9:1 multi-core unun housed in a NEMA enclosure box (4″ x 4″ x 2″) with top stud/eyebolt output used to translate a 50 ohm input up to 450 ohms at RF power levels up to 5000 watts PEP (SSB) when used with a matched load. Usable to 61 MHz under 2:1 SWR with matched load.
Great for end fed antennas - FT-8 and digital mode power ratings are approximately 30% of PEP ratings into a matched 450 ohm load. For non-resonant end fed antennas, you will need a feed line choke on the coax. See typical antenna configuration notes below for details.
Non-Resonant End Fed Antenna Configuration NotesTutorials
50:450 ohm (9:1) CUBE™ Unun, 1.8-31 MHz, 5 KW PEP, End Fed Antenna
Product Details
Input ohms/Output ohms: 50 in / 450 out
Frequency Range < 2:1 SWR (MHz): 1-31 MHz
PEP Power Rating (watts): 7500
Model CU-9-5000 is a 9:1 multi-core unun housed in a NEMA enclosure box (4″ x 4″ x 2″) with top stud/eyebolt output used to translate a 50 ohm input up to 450 ohms at RF power levels up to 5000 watts PEP (SSB) when used with a matched load. Usable to 61 MHz under 2:1 SWR with matched load.
Great for end fed antennas - FT-8 and digital mode power ratings are approximately 30% of PEP ratings into a matched 450 ohm load. For non-resonant end fed antennas, you will need a feed line choke on the coax. See typical antenna configuration notes below for details.
Non-Resonant End Fed Antenna Configuration Notes
