Inverted L antenna with radiator and counterpoise for simple installation - choose 80/160 meters and 1.5KW/5KW feed line choke included inside weatherproof enclosure. Separate counterpoise and ground connections
* Complete package - just add coax
* works single band with ease
* can be configured as vertical or inverted L configuration
* Choice of 1.5K, or 5KW PEP rated choke to suit power needs
After many requests we have created a compact, special interface box with internal feed line choke and separate connections for counterpoises (not grounded) and ground connection. The 1:1 choke keeps RF current off the outside of the coax braid and on the antenna where it belongs. The extra choking action also means that the coax feed line will not act as a radiator causing unnecessary RF interference (RFI).
80 M radiator/counterpoise is 70 Feet (you get 1 each) - adjust length to your favorite frequency
160 M radiator/counterpoise is 130 Feet (you get 1 each) - adjust length to your favorite frequency
Antenna is tuned to you favorite frequency by shortening the counterpoise (roll it up or cur length) while keeping the radiator length constant.
Choose 1,5KW PEP or 5KW PEP options.
1.5KW and 5KW are in 4" x 4" x 2" enclosure. 1.5KW is 3 pounds, 5KW is 5 pounds. 2 antenna insulators are included.
ADD CMNF-1500 (1.5KW) or CMNF-5000 (5KW) common mode noise filter at radio end of coax to reduce common mode noise up to 6 "S" units on long coax runs!
A simple ferrite ring filter on the DC power line can help suppress the RFI noise affecting the victim device or keep the DC power cord from acting as an antenna and radiating RFI into other victim devices. This kit is also useful on laptop computer supplies, routers, cable modems, wireless phone charges, etc.
Installation is quick and easy: Just wrap the DC power cord through the center of the ring filter as many times as you can and reinstall. For best results with long DC power lines, use one at the ring filter at the wall wart end (to prevent the wall wart power supply from using the DC line as an antenna) and another at the DC plug end (to prevent the electronics in the powered device from using the DC power cord as an antenna). Typical installation is shown below:
The filter suppresses RFI in from .1-100 MHz. Inside diameter is 3/4 inch/19 mm.
Since most households and office environments have multiple wall warts we offer the Wall Wart RFI Filter kit in bulk quantity packages.
Known RFI Generators include Roku/Sling-TV power adapter - Interference heard in the AM broadcast band and harmonics. Also many ethernet Cable/DSL modems, cell phone chargers, computer power adapters have the same issue: using the AC or DC side of the power supply as a radiating antenna. RFI solution is to use a linear power supply, change adapters or wall wart ferrite filters