Sorry to join this thread rather late - yes, they sound fine, the bandwidth
limitation almost invariably being imposed by the receiver, especially
single-tuned
ferrite rods, a limitation which need not apply to the transceivers with
wideband front-ends most amateurs are using now. The percentage b/w does
seem impressive, but
radio engineers in other disciplines would probably feel underwhelmed - how
about VHF broadcast radio or UHF TV, where several Tx channels are combined
into one antenna (especially in Wales!)?
The important point I want to make is that to think about antenna bandwidth
is rather misleading - that bit of wire for LF has as much b/w as you like,
but it
is the antenna *system*, dominated by the matching network, which has
limited
b/w. Mike has mentioned the BBC Droitwich Tee antenna, and I recall that
this is
matched not by a sharply resonant tuning coil, but by cascaded and tapered
L-C matching networks (perhaps 3-sections). I suppose this starts to look
like a bit of transmission line with tapered impedance, and is easily
modelled to show the increased bandwidth.
Regards - Julian G3TFR
----- Original Message -----
From: Dr. Tom Gruis <[email protected]>
To: <[email protected]>; <[email protected]>; <[email protected]>
Sent: Thursday, September 06, 2001 2:50 AM
Subject: LF: Long Wave Broadcasting
Hi from Iowa, USA, EN31do
This my seem a silly question, but I am curious.
How is the audio quality of European LW BC stations? The bandwidth
percentage is really something on those frequencies.
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