Bob,
Thanks for clearing up the low latitude ducting question. You're right, I
let the low latitude aspect get completely past me when I asked the
question. You're explanation clears up a lot of the east/west path
uncertainties I've had.
However, you (and maybe W4ZV) are going to have to work a lot harder to get
me to believe the difference between JA and EU from this QTH can be
completely explained by auroral effects.
I am assuming the "auroral zone" can be defined by the satellite images
depicting auroral activity and intensity. Perhaps that assumption is
incorrect. If it is correct, then it's hard for me to accept that the
minimal or close miss passage of signals through the zone from central and
southern EU would account for the 30+ dB of difference in path loss I see
compared to the JA path.
I'll buy the concept for Scandinavia, that's a given. When I hear those
guys on, the signals always have an aurora signature and I never hear them
at the same time as the other EU stations. Eastern EU and middle east have
never been heard by me at this QTH. Those are truly polar paths and, baring
divine intervention, I will never hear them with the RX conditions I have
here.
If I can hear DL, I can hear EA, I, G, etc. The GCB from me to EA is
47°/8970 km., clearly south of what I consider the auroral zone on a quiet
night, and little different than the path to JA. If a few degrees make that
much difference, why don't I see it between DL (34°) and EA(47°)?
On a slightly different note, I listened for 9V1PC for 90 minutes prior to
my sunrise this morning. There was no detectable signal during that time
with the RX antenna swept from 250° through 315°. GCB from me to 9V is
310°. KC7V, 40+ miles north of me, did copy him at 449, but Mike's noise
floor is many dB lower than mine. JA's were loud and easily worked (310°)
up until 60 minutes before my sunrise when they disappeared. Did they all
go to bed or did prop go sour?
73,
Larry - W7IUV
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