On Mar 9, 1:51 pm, wrote:
Subject -was- Antenna Switch and MW Coverage
-
- I'm looking for an antenna switch (2 antennas, 1 receiver)
- and I've noticed that many are rated for 1.8-30 MHz, such
- as the MFJ models.
-
- Are these typically attenuating the MW band,
- or can they be used efficiently down to 500khz?
-
- -Brian
-

Brian,

Shortwave Radio Antenna Switch and AM/MW Band Coverage

The problem is not on the Lower-Side below 1.8 MHz : The
actual 'problem' will manifest itself on the Higher Side lets
say beyond 300 MHz [VHF]. They all work great for the
AM/MW Radio Broadcast Band (BCB) 500 kHz to 1.8 MHz;
and all the way down into the Long-Wave Radio {Low
Frequency Band}.
http://cache.eb.com/eb/image?id=6887&rendTypeId=4
http://cache.eb.com/eb/image?id=4621&rendTypeId=4
http://en.wikipedia.org/wiki/Medium_Wave
http://en.wikipedia.org/wiki/Long_wave

Note - The MFJ Antenna Switches all have a greater-than
50 dB Isolation at 500 MHz.
http://www.universal-radio.com/catalog/switch/2811.html

MATTER-OF-FACT - For the most part it ain't a 'problem'
at all since these Switches are designed and being sold to
High Frequency {Shortwave} Radio Users and Listeners.
The 1.8 MHz to 30 MHz Frequency Coverage Specification
is simply stated to communicate to them that the device is
good for the entire High Frequency {Shortwave Radio} Band.

The vast majority of these devices are fitted with SO-239
Jacks to accept PL-259 Plugs; that themselves are fitted
to RG-8 & RG58 and their 'variations' of Coax Cables which
is/was widely used in the AM/MW Radio Applications.
http://en.wikipedia.org/wiki/Coaxial_cable
http://en.wikipedia.org/wiki/10base5
http://en.wikipedia.org/wiki/Amateur_radio

Read this Message Thread :
Antenna Switches - What's In Your Radio Shack ?
http://groups.google.com/group/rec.r...3e12e98f1a6b8a

Coax Switching Boxes Opinions ?
http://groups.google.com/group/rec.r...bde2a6f7a3aede

One Antenna and Two Radios = One Antenna Switch ?
http://groups.google.com/group/rec.r...3d96b7a4b7af4b


hope this helps - iane ~ RHF {pomkia}
Shortwave Listener (SWL) Antennas Group = http://tinyurl.com/ogvcf
GoTo = http://groups.yahoo.com/group/Shortwave-SWL-Antenna/