On 10/20/22 1:50 PM, Lux, Jim wrote:
On 10/20/22 12:08 PM, Pete Smith N4ZR wrote:
Not blaming Ed, but is this for real? I wonder what all the 75 and
160M phone guys think of this?
73, Pete N4ZR
Check out the new Reverse Beacon Network
web server at<https://reversebeacon.net>.
For spots, please use your favorite
"retail" DX cluster.
On 10/20/2022 1:43 PM, Edward McCann wrote:
“In the low-frequency band, bandwidth is quite scarce for any
top-loaded
antenna type and must be carefully evaluated in order to obtain
good-quality speech transmission. In this band, this kind of antenna is
practically the only choice, due to the antenna’s size. In the low
end of
the medium-frequency band, it is quite difficult to obtain a
high-fidelity
bandwidth.”
Physically short antennas for MW (implied by top load) could be quite
narrow band. "high fidelity" would be 10kHz BW. that's 1% at 1 MHz
and 2% at 500 kHz.
If he's talking real LF (e.g. 100 or 300kHz, getting 10kHz BW with a
toploaded system would be challenging).
For comparison, a run of the mill dipole with thin wires is about 5%
bandwidth. At 300 meter wavelength (1 MHz) any sort of tower is
essentially a "thin wire".
A full size antenna at 100 kHz (lambda = 3km) is a monster.
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