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