Topband: Daytime on 160 and Conditions
aa7jv at atlanticbb.net
Wed Nov 21 07:54:51 EST 2018
I am out at C6AGU (FL14) with good 160 m TX and RX antennas.
Last night, around 05:00 UTC, I heard a ZS station calling me. I thought no
way, I must have copied the call wrong: the gray-line window showed full
daylight there. Well, not really: I just got an e-mail from him that he was
calling me. While a contact at high noon may be very unlikely, a couple of
hours after or before sunset, it is perfectly possible. I hear EU out here
from about 4:30 PM local time, almost two hours before my sunset.
For the past three days I have been experiencing unusual conditions. Signals
from EU are present on my EU RX antenna and SDR receiver at between -110 and
-80 dB. (I don't know the absolute levels, it is just on the band-scope of
the SDR.) The noise floor is around -120 dB. However, there is a fluctuating
noise that I have not heard before: The noise floor rises in a one or two
seconds from -120 to -85 dB, stays there for a second or two and then drops
back to -120 dB. Through the headphones it sounds like QSB. But the signal
levels are steady. It is the noise that has QSB, completely masking all but
the strongest signals at its peak.
I am on a small, uninhabited island, about 10 miles from the nearest
civilization -- if you can call a small Bahamian village that. It is
normally very quiet here. The noise is wide-band and is at a similar level
both on my NE and NW RX antennas. That makes me think that it may be coming
in at a high angle, where my RX antennas do not have much directivity.
Is anybody else experiencing this noise?
TKS and 73,
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