On 6/13/2026 5:57 AM, Carl Luetzelschwab via Topband wrote:
160m has an approximate 10 dB increase in man-made noise in a
residential noise environment and an approximate 5 dB increase in man-made
noise in a rural noise environment.
80m has an approximate 8 dB increase in man-made noise in a
residential noise environment and an approximate 4 dB increase in man-made
noise in a rural noise environment.
Thanks Carl. I've seen this cited before.
Several observations. The paper notes increases on the order of 14-20 dB
in urban environments, and this was published in 2019, probably from
data in a subsequent year (it takes time to do this stuff and publish
it). Assuming 2018, this 8 years later, and it's gotten much worse.
I'm sticking with 20 dB as a WAG.
BTW -- there are many definitions of power articulated in dB, each with
a reference. The most common for dBm I'm familiar with is dB with
respect to a 1 mW, and our most common citation in ham radio is tied to
the signal at the input of our receivers, displayed on an S-meter. But
the real quantity is field strength in mW/m, while the voltage at the RX
input is totally dependent on the antenna, its characteristics, and the
feedline. In other words, dBm at the RX input is meaningless.
73, Jim K9YC
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