"Roy Lewallen" wrote
Once you have enough signal and noise to overcome
your receiver's internal noise, there's no advantage of any
further increase, since there's no improvement in the
signal to noise ratio.
__________________

Pardon the thread drift, but making the receive antenna directional can
improve system SNR by reducing the total noise voltage delivered to the
receiver input, as a ratio of the desired signal.

RF

Yes. My response was intentionally simplified. Making a directional
antenna is often not a viable option for an SWL, because they typically
operate over a wide frequency range, and want to receive signals from
many directions. This pretty much limits them to something like a
rotatable log periodic antenna. Wire antennas can be made directional,
but typically only in fixed or a small number of directions, and with
directional patterns that change with frequency. Within the range of
discussion, then, I don't believe it's realistic to attempt a
directional antenna. The advertised antenna certainly doesn't produce
any advantage in this regard.

Roy Lewallen, W7EL

Richard Fry wrote:
"Roy Lewallen" wrote

Once you have enough signal and noise to overcome
your receiver's internal noise, there's no advantage of any
further increase, since there's no improvement in the
signal to noise ratio.

__________________

Pardon the thread drift, but making the receive antenna directional can
improve system SNR by reducing the total noise voltage delivered to the
receiver input, as a ratio of the desired signal.

RF