Topband: No 160m Sunrise Peak

Guy Olinger K2AV k2av.guy at gmail.com
Wed Jan 31 15:31:14 EST 2018


I actually wasn't hearing band peaks either, until I got to thinking about
that, and went digging in the RBN stats. The peaks are there. So what gives?

One of the human factors kinds of things that bears on a discussion of
"peaking" has to do with how a human being perceives "louder". One clue
that this is not a simple thing is how people with low output RX antennas
often think a signal is "worse" on an RX antenna vs. the TX antenna when
the wanted signal on RX antenna actually has a quite better signal to noise
ratio.

If observing such an operator real time, you can see that in order to be
perceived as "better", the RX antenna channel needs to be preamplified
until the *noise* in both channels is equal. Then our brain's subconscious
aural processing center will identify the now louder RX antenna desired
signal as better, >>because it is louder<<.

The subconscious aural processing responsible for our remembered feeling
about the signal equates louder with better until the volume becomes
uncomfortable.

Likewise, our remembered idea of signals getting louder has to do with
audio volume on the receiver being louder. I find that these things sound
louder on my MP and 75A3, but do not on my K3. The difference is that the
K3 has *digital* AGC which can do things with signal processing subroutines
impossible or too expensive with traditional analog AGC processing.

In my K3 I have the AGC set so that it's processing is absolute at a
certain output volume that is not to be exceeded. Going by volume,
everything out of the noise is the same volume once it's loud enough to hit
my maximum desired volume set in the AGC. None of my analog RX can approach
this level of control with their AGC circuits. I'm sure it was possible
back then with complex analog circuitry but not with the simpler circuity
appropriate for profit margins on equipment targeted at the ham market.

With the K3, the only way I am going to be able to tell a peak is by
keeping my eye on the S meter.

But when I'm in a contest focused on logging and where the next multiplier
is and keeping my typing clean, I find I almost never look at the S meter
LED's.

But the effect of sunrise, etc, are clearly seen on RBN numbers.

I see the RBN numbers reflected in the thinning out or thickening of
contest stations in the P3 spectral display. That's my digital age
indicator that it might be time to change bands or go get a nap.

But it's not in the audio volume of signals any more. I don't have to put
up with ear piercing volume of loud stations when I'm only left with the
weak hard-to-work ones toward the end of the contest.

There are so many nuanced changes from the old days with the new digital
processing. I can do K3 and MP side-by-side listening, and the K3 clearly
hears and demodulates better than my MP. I prefer the audio "sound" of the
MP to the K3, but I can dig stuff out better with the digital processing of
the K3. The diversity processing of the K3 opens a new usefulness of my
brain's aural processing -- spreading out the audio from two different
antennas across a "sound stage" and let my brain's built in ability to pick
out a single voice in cafeteria racket do the same digging out a discreet
signal from noise spread across the "sound stage".

I'll take the digital. And not worry much if I don't "hear" the band peaks
like I used to.

73,

Guy K2AV.

On Wed, Jan 31, 2018 at 1:02 PM, Larry via Topband <topband at contesting.com>
wrote:

> Yes there is most certainly a peak at sunrise most days.
>
> You can monitor the RBN and see your signal strength at specific
> locations. I do that from Arizona with Japan RBN stations.
>
> During this last contest,  second day produced a great pre-sunrise opening
> to western Europe. 40 EU logged in the hour. Some G stations peaking S9
> plus at their sunrise.
>
> In my many years of 160 activity I have made about 10 true LP contacts.
> All have been between 10 minutes before sunrise to 10 minutes after. My
> last zone was a contact with EY8MM at exactly sunrise.
>
> There are reasons for this kind of opening but would take someone smarter
> than me to explain it.
>
> 73,
> Larry
> N7DD
>
> Sent by Larry
>
> On Jan 31, 2018, at 6:37 AM, k8gg at voyager.net wrote:
>
> Roger, Et. Al.,
>
> On the contrary, Sunday morning in the CQWW 160 CW there was a peak
> observed from Michigan.
>
> A very weak EI4???  called me about 0730Z without a QSO.  Then G3PQA
> popped up solid and we made a QSO easily.  That was followed by an EI2 who
> was good copy, F6ARC, and a DJ4 in total sunrise about 0745Z.  They were
> 579 to 589 despite contest intermod at W8RT, the Low-Band contest station
> near Battle Creek, Michigan.  Also an LA station was hunting and pouncing
> at that time and, although he did not call me, he was louder than when
> calling CQ and running on a fixed frequency.
>
> 73,  George,  K8GG, 2nd operator in a Multi-Operator Hi-Power entry.
>
>
>
>
> >
> > Just to re-state something I posted a few weeks ago . . .
> >
> > I made a point of checking signal strengths last weekend in the CQ WW.
> >
> > Once again, there was absolutely NO increase in signals strengths around
> > our
> > Sunrise (0730Z), and if anything they started to drop off.
> >
> > This was regardless of how far west the stations were.
> >
> > Don't ask me why . . . in the old days, you would only bother coming on
> > around Sunrise to work DX, as signals would increase by as much as 10 -
> > 20dB.
> >
> > Roger G3YRO
> >
> > _________________
> > Topband Reflector Archives - http://www.contesting.com/_topband
> >
>
>
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