> A principle implication of this on a similar scheme for
160m is that the
> beacon
> signals do not have to be anywhere near as potent as a
normal
> 'communications' level signal: A key factor often
missing in discussions
> about
> beacon networks is the high degree of involvement and
hardware usage on
> behalf of the beacon-keeper; that essentially as long
as he has the beacon
> running, he is out a radio, a big antenna, and as a
consequence use of the
> band. Reducing the ERP to enough to still allow
ultra-narrowband sensing
> means that the transmitter need not even be a radio (!)
and the antenna need
Hi Steve,
A copy of the VLF experimenter system would require
thousands of people around the world active on 160,
including DX'peditions, use very specialized transmitting
and receiving systems so they could SWL low power beacons.
That's OK if the target audience is a small group of
experimenters who enjoy specialized receiving techniques
over modest distances. In other words a similar target group
who listen to weak signals on VLF would listen to flea power
160 beacons just to find out what they could hear.
Since very few (if any) operators would want to or even be
able to use specialized receiving techniques, I think it
would be a gigantic flop. There would be a bunch of dog-gnat
power transmitters taking up space without productive
results so far as the vast majority of users of the band are
concerned.
The actual goal is for stations with common simple equipment
to just spin a dial to one spot and determine quickly if the
band is open, say from the NE USA or SW USA to China, or
perhaps some DX operation on a remote island with a tent on
a beach and generators.
The system needs to employ normal CW transmitters, just like
the other HF propagation beacons, so anyone who can copy CW
with a standard receiver can hear the beacons and determine
how and where the band is open. The only exception is for
160, because of higher path losses and noise, the
transmitters and antennas would have to be a bit better.
73 Tom
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