CUBE Feed Line Choke/Line Isolator Unun, 1.5KW, 1.8-65 MHz, -38dB SuppressionProduct DetailsBrand: Palomar EngineersEffective Frequency Range (MHz): 1.8-65 MHzPEP Power Rating (watts): 1500Estimated Insertion Loss (db): .10Input Connector Type: SO-239 femaleOutput Connector Connector Type: SO-239 femaleGround Connector (Y/N): noneEnclosure Size (LxWxH inches): 4 x 4 x 21500 Watt Rated 1:1 CUBE™ Unun
Th CU-1-1500 unun is useful as common mode feed line chokes or coax to antenna interfaces. SO-239 output models can also be used with balanced antennas if a short coax cable “pigtail” is used on the output and connected to the antenna. Rated 1500 Watts PEP from 1.8-61 MHz.
Use as line isolator, antenna interface, or as a common mode choke to keep RF on the antenna and off the outside of the coax braid.
Much more effective then our sleeve feed line chokes due to our exclusive Multimix(TM) multi-core topology using high permeability ferrite cores which provides a high choking impedance over a broad frequency range.
Typical common mode suppression is 20-38 dB (up to 6 "S" units) from 1.8-61 MHz reduces common mode current! For most effective results, use 1 choke at the antenna and another at the radio. Helps reduce noise floor too by choking off common mode neighborhood noise picked up on outside of coax braid.
Optionally available with both input and output on same side for certain installations and wall mounts available on each side for both models.
Choose SO-239 UHF or N connector input/output connectors
1500 Watt Rated 1:1 CUBE™ Unun
Th CU-1-1500 unun is useful as common mode feed line chokes or coax to antenna interfaces. SO-239 output models can also be used with balanced antennas if a short coax cable “pigtail” is used on the output and connected to the antenna. Rated 1500 Watts PEP from 1.8-61 MHz.
Use as line isolator, antenna interface, or as a common mode choke to keep RF on the antenna and off the outside of the coax braid.
Much more effective then our sleeve feed line chokes due to our exclusive Multimix(TM) multi-core topology using high permeability ferrite cores which provides a high choking impedance over a broad frequency range.
Typical common mode suppression is 20-38 dB (up to 6 "S" units) from 1.8-61 MHz reduces common mode current! For most effective results, use 1 choke at the antenna and another at the radio. Helps reduce noise floor too by choking off common mode neighborhood noise picked up on outside of coax braid.
Optionally available with both input and output on same side for certain installations and wall mounts available on each side for both models.
Choose SO-239 UHF or N connector input/output connectors
TECH NOTE: We also stock RFI kits to protect effected devices such as garage door openers, computers (laptops, desktops), dsl/cable routers, ethernet hubs and many more devices. If you run a high powered RF amplifier in your ham station also consider a linear amp RFI kit which will cut down RFI transmitted by your station. Remember there is always a “transmitter” and a “receiver” of RFI and the quest is to find and choke the “path” the RFI has selected – you need to add ferrites to both the transmitting side and the receiving side to eliminate RFI problems. The RFI-HTS kit only helps suppress RFI on the receiving side.
Typical RFI Problem/Solution:
Hello, I am Larry, a ham operator and I am having interference issues with my Direct TV system. My station is a FT450D through an Ameritron ALS-600. From the amp through a coax switch to choose between an OCF dipole or an Hustler 5BTV vertical. Any power over 100 watts and my DTV goes off the air and must completly reboot/format. Coax is RG-8. The DTV dish is pointed away from the dipole and separated by about 25'. DTV was totally useless! They suggested I not talk on the radio while she is watching TV! Please help me with a reasonable, cost effective soultion. (The wife gets really pissed when I shutdown the tv!) Thank you, Larry
Hi Larry,
Your RFI problem is quite common and is usually a sign of either a radiating coax feed line or reception of your radiated signal (source) by the Direct TV (the victim) through either the AC power lines acting as “antennas” for your ham signal or the coax braid of the satellite antenna acting as an antenna for your signal.
The solutions are straight forward:
1. To make sure your feed line is not radiating you need a feed line choke at each antenna feed point (also makes your antenna work better since it is not using the coax as part of the antenna). You can use our simple Kit 110 with 5 snap on chokes on each antenna for this purpose. Part # Kit 110 at $27.50 each – one for each antenna. These chokes will keep your feed line from radiating and coupling into your ac power lines. INFO HERE
2. The radiation from your antennas themselves may also be getting into the ac power lines and coax braid of the Direct TV antenna so you need to protect the victim receiver. Depending upon the sophistication of your direct TV setup (e.g. home theater, dvd, tape player, sub woofer speakers, etc), the path of the RFI may be coming thru the AC power lines of any connected device to the video including the video monitor itself! To help solve this problem we have a home theater RFI kit for up to 5 devices (you need a minimum of two – one for the Direct TV receiver(AC and coax input) and another for the video monitor AC power lines and HDMI or video input cable. Our kit part # is RFI-HTS. INFO HERE
These items should help reduce the RFI and let you operate on the air while your wife watches TV.
Bob Brehm, AK6R
Chief Engineer