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:
Also available as a balanced output – CB-5-1500
Kenwood TS-990 Elite Transceiver RFI and Noise Reduction Kit, RFI Range 1-60 MHz, 24 FiltersProduct DetailsMPN: RFI-KENWOOD-(()Type: NEWCountry/Region of Manufacture: United StatesRFI Suppression Range (MHz): 1-60 MHz# Ferrite Filters: 24Enclosure Size (inches): n/aTypical Use:: AC/DC power, RF output x 4, multiple I/O linesThe Kenwood TS-990 is an exceptional radio and deserves an excepitional RFI and noise reduction kit which we have designated as the "ELITE" series of Transceiver Kits. This kit is designed to be installed on your radio transceiver to reduce Radio Frequency Interference (RFI) caused by common mode current on the multiple coax connectors of your radio, the AC power input, USB, DMU, Audio, rotor, amplifier ALC/Send, mouse, mic and additional interconnect cables. The ELITE Kit has 6 ferrite ring (1.4" ID) filters and 18 ferrite snap on (1/2") filters and instruction manual.
This kit will help reduce or eliminate:
1. “Hot mic” RFI caused by poor grounding of antennas or common mode currents from linear amps feeding unbalanced (coax fed) antennas without baluns/line isolators.
2. RFI to neighbor’s electronic devices including audio/video systems, computers, telephones, garage door openers, etc.
3. RFI to your other radios, audio/video systems, computers, telephones, etc.
A side benefit is a reduction in noise floor in your receiver depending on the amount of noise being introduced by common mode currents (which are blocked/reduced by the chokes in this kit).
These chokes use a special mix of ferrite core material that is effective in suppressing radio frequency interference from transmitters and high noise floor on receivers.
The split beads beads are easy to use, don’t require modification of the protected equipment and work in almost all cases, even when plug-in filters fail.
Use of the chokes often helps cure SWR problems between transceiver and a linear amp and between transceiver and antenna tuner or direct to antenna. The DC power line choke helps keep common mode current out of the power line which could cause interference to other devices connected to the same power line if not suppressed.
For additional RFI suppression, use a feed line choke at the antenna feed point to suppress common current on the coax feed line and a coax noise filter at the radio end of the coax to reduce common mode noise.
If you use a linear amplifier use an amplifier RFI kit for additional RFI interference suppression.
The Kenwood TS-990 is an exceptional radio and deserves an excepitional RFI and noise reduction kit which we have designated as the "ELITE" series of Transceiver Kits. This kit is designed to be installed on your radio transceiver to reduce Radio Frequency Interference (RFI) caused by common mode current on the multiple coax connectors of your radio, the AC power input, USB, DMU, Audio, rotor, amplifier ALC/Send, mouse, mic and additional interconnect cables. The ELITE Kit has 6 ferrite ring (1.4" ID) filters and 18 ferrite snap on (1/2") filters and instruction manual.
This kit will help reduce or eliminate:
1. “Hot mic” RFI caused by poor grounding of antennas or common mode currents from linear amps feeding unbalanced (coax fed) antennas without baluns/line isolators.
2. RFI to neighbor’s electronic devices including audio/video systems, computers, telephones, garage door openers, etc.
3. RFI to your other radios, audio/video systems, computers, telephones, etc.
A side benefit is a reduction in noise floor in your receiver depending on the amount of noise being introduced by common mode currents (which are blocked/reduced by the chokes in this kit).
These chokes use a special mix of ferrite core material that is effective in suppressing radio frequency interference from transmitters and high noise floor on receivers.
The split beads beads are easy to use, don’t require modification of the protected equipment and work in almost all cases, even when plug-in filters fail.
Use of the chokes often helps cure SWR problems between transceiver and a linear amp and between transceiver and antenna tuner or direct to antenna. The DC power line choke helps keep common mode current out of the power line which could cause interference to other devices connected to the same power line if not suppressed.
For additional RFI suppression, use a feed line choke at the antenna feed point to suppress common current on the coax feed line and a coax noise filter at the radio end of the coax to reduce common mode noise.If you use a linear amplifier use an amplifier RFI kit for additional RFI interference suppression.
