[Elecraft] 6 Meter Questions - OT

[Bill W5WVO]

Generally all very true! Except for when it isn't. :-) One of the things you 
can depend on about 6m -- probably the only thing, actually -- is that it will 
fool you. I've experienced 6m sporadic-E openings when signals were very 
strong and rock-solid for hours on end, and coming in from multiple azimuths. 
All this means is that there are many sporadic-E clouds, they are very hot, 
they are very large, and they aren't moving very fast. :-) All "unusual" 
characteristics for sporadic-E, by the book, yet there are many such openings 
every summer across North America and Europe.

In the doctor business, it's called differential diagnosis. It's basically a 
process of elimination, and it's never 100% certain. Basically, though, if 
you're hearing signals from well beyond ground wave distance, and you KNOW it 
isn't F2 because the F2 MUF is way below 50 MHz (as it is now), and it's not 
aurora (no flutter/distortion, and/or you live too far south to EVER hear 
aurora), and it's not meteor scatter (signals are stable for more than a 
second or two), and it's not troposcatter (signal is originating from more 
than 350 or so miles away and are strong) or tropoducting (unusual on 6m, but 
happens) or D-layer ionoscatter (don't even ask), and it's during a period of 
the year where you would expect sporadic-E (May-August, November-January) --  
then it's probably some flavor of sporadic-E: single-hop, 
multi-hop/earthbounce, multi-hop/extended-path, or some combination. 
Sporadic-E propagation even combines with other modes: sporadic-E plus 
meteor-scatter, sporadic-E plus tropoducting, and sporadic-E plus F2 have all 
been observed on multiple occasions. During solar maxima (wait three or four 
years from now), it is not uncommon to have F2 and sporadic-E propagation 
happening at the same time -- sometimes combining on a path, sometimes acting 
separately.

And sometimes, you are just very hard-pressed to come up with ANY plausible 
propagation model to explain what you just heard/worked. Yet, there it is.

You gotta love this band. :-)

Bill W5WVO


Simon Brown (HB9DRV) wrote:
> Volatile signal levels - can be there for a few seconds to a few
> minutes or even an hour. Signals you receive come more-or-less from
> roughly a single direction (N, S, E, W).
>
> A big advantage of the bandscope on the IC-7800 / IC-7700 - you
> suddenly see the band coming to life.
>
> Simon Brown, HB9DRV
>
> --------------------------------------------------
> From: "Richard Davis" <richard at aroundwood.com>
>>
>> What are the characteristics of signals on 6 meters that are
>> propagated by sporadic-E?  How would I recognize that s-E is in
>> effect?
>
>
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