The Par End-Fedz® are a full length half wave dipoles, but with an important difference. The coax connector is at one end of the dipole, where it is most needed. These antennas can be mounted horizontally, vertically or as a sloper. No ground plane or counterpoise is needed. Portable operation could not be easier. Simply hang the far end from a tree limb–the coax is at the bottom. Hang it up in a hotel window or string it up in the attic. End insulators are supplied making suspension easy.
[easyrotator]erc_73_1339683507[/easyrotator]
HF EndFedz® (Patent Pending)
The UV resistant ABS plastic housing encloses an efficient matching network allowing the antenna to be fed with common 50 ohm coaxial cable. All hardware is stainless and the SO-239 connector is silver/teflon. The radiator wire is custom made for us in 21 mile runs. It is a #18 gauge stranded copperweld with a tough polyethylene jacket. Breaking strength is 200# and, unlike the vinyl jacket found on the vast majority of antenna wire, the polyethylene jacket is 100% UV stable, very tough and slippery – almost like Teflon®. One end comes with a #10 solder lug making attachment to the matchbox simple and allowing the radiator portion to be replaced if ever necessary. Power rating is a conservative 100 watts. Lightweight (the 20 meter version is only 0.5 pounds), they are ideal for portable work. The all black construction makes them difficult to see.
Videos
- YouTube Videos
- Mountain Topping with the EndFedz
- See Oleg, RD1AN operate portable outside St. Petersburg using an EF-20 and FT-817
EHAM Reviews:
http://www.eham.net/reviews/detail/3632
http://www.eham.net/reviews/detail/5105
NO COUNTERPOISE REQUIRED!
We are often asked (or sometimes even TOLD), certainly you must have a counterpoise for end fed antennas. Over the years, this has been debated by many experts. Our contention is that it is NOT an absolute requirement and with quality components, circuitry with novel design, you can drastically reduce and even eliminate the need for counterpoise at the feed point.
Explanation: Of Fields and Feedpoints – John Huggins
EF SWL
The Par Electronics EF-SWL is an end-fed short wave antenna optimally designed for 1-30 MHz reception. The radiator is 45 feet of genuine #14 black polyethylene coated Flex-Weave wire.
The wire itself consists of 168 strands of #36 gauge woven copper. This material is very strong yet can easily be coiled like a rope for portable work. The UV resistant matchbox houses a wideband 9:1 transformer wound on a binocular core. Unlike other transformers, external stainless studs on the matchbox allow the user to configure the primary and secondary grounds for best noise reduction at their particular location. Examples are given in the manual. Output is via a silver/Teflon® SO239 UHF connector (ready to accept a PL-259). Lead-in coax cable is not provided.
The radiator also attaches via a stainless stud allowing it to be removed, or replaced with a different length radiator for experimental purposes. The included manual shows typical radiation patterns for selected frequencies through out the HF spectrum. (This is a receive-only antenna).
See the Monitoring Times review of the EF-SWL.
See the EHAM reviews of the EF-SWL.
For a better understanding of low noise and grounding, look at the following links:
http://web.archive.org/web/20030701222251/anarc.org/naswa/badx/antennas/low-noise_antenna.html
http://groups.google.com/group/rec.radio.shortwave/msg/5fd8fe1179a5c6c8