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Cluster Activity

Spots per uW band today:
UK spotter or spotted only.

Solar data:
SFI
270
A-Index
5
K-Index
0
Exp.K
0
Sunspots
187
Activity
act
GMF
act
Aurora?
no

My Weather

ArrayDate:03/11/24 Time:12:53
Temp:13C
Wind Speed:0mph
Wind Dir:225deg
Pressure:1027.91mB
Humidity:118%
Dew Point:16.6C

After the recent NLOS discussions i have been testing my equipment out and finally got out today to do a NLOS test.

Tx was Phlatlight pt-54 with original lenses (they give roughly 25deg beam) into a third lens to give ~11deg beamwidth. LED was running at about 2A, signalling was a 1700Hz tone plus JT65C on odd minutes.
This was aimed so that the bottom of the illumination area was just in line with the horizon, so vertical coverage was 1-12deg.

Rx was 25x25cm Fresnel lens and KA7AOI circuit with single BPW34, the first optical receiver head i built up back in 2009 maybe.

Two sites were used at the /p location, Tx was at home:
Potto (7.9km): NLOS and trees on horizon
Swainby (10.5km): LOS but TX not visible, obstructed by trees at ground level.

I first went to the LOS site and found my signal within a minute or two, quite amazing as i was just roughly pointing towards home.
I think i could detect the direct signal on the horizon although i could not see it in the finder scope but 4-5deg of elevation gave best signals, peak was -6dB JT65C with light patches of cloud. Signals were still there at -10dB JT65 with no clouds present.
To confirm i was just not hearing my home LOS signal i stopped at another spot on the way back which was NLOS and also had trees obstructing the horizon, Signals peaked at around 6-7deg elevation this time and the best decode i got was -4dB JT65, a little more cloud this time.

It's my first time trying the scattering methods and it certainly does work!
One thing i must do next time is turn off my phone, causes all sorts of noises on the optical receiver even in flight mode, a lot of that you can see in the spectrum.
I have 20dB of margin for the next tests...
The sky was quite bright due to the illumination from Teesside, i don't think that helps much!

Some photos...

Paths


Rx Spectrum


An audio recording from the First Location

Potto Rx Site View













Last page added:25/03/00 18:32
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