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[K0IZ]

I worked an EA3 on Friday, big signal, about 20db over (calibrated S-meter).  I also heard an echo, about 1/10 to 1/20 second delay.  Probably would have rated about an S5, easily audible.  I commented to EA3 who said he was beaming over the north pole.  I assume with that sort of delay I was hearing long path plus short path? 

[KA2DDX]

I would assume so. I've had the same experience recently on 20 and 17m cw.

[K1VSK]

The difference between short and a skewed path over the Pole from your QTH is too close in direction to differentiate. Most beam widths aren’t that narrow. Plus arctic flutter can influence how you hear signals that way.

Echos are quite common when working Europe when beaming due West and they are beaming LP to the East.

[K0IZ]

Maybe twice around?  No flutter on either signal or echo, nice and clear, audible but down a bunch from the main signal.

[N0GV]

Long path vs short path echo can be calculated as:

[LP(miles)-SP(miles)]/186000 = echo delay.

If the SP is 4000 miles then the LP is~20000 miles and the echo delay should be about 16000/186000 = 1/11 seconds.

Timing for an EA into K0 should be as in the example above (approximate  only!). Hence it was a SP-LP delay "echo".

Enjoy,

Grover

[K1VSK]

Maybe twice around?  No flutter on either signal or echo, nice and clear, audible but down a bunch from the main signal.

Not a chance given the current conditions. Did you have diversity receive on?

[WA3SKN]

Assumimg your time measurement is accurate...
186000 x.1= 18,600 miles.
186000 x .2= 37,200 miles.
So what multi-path route would add those miles?

-Mike.

[N0GV]

Assumimg your time measurement is accurate...
186000 x.1= 18,600 miles.
186000 x .2= 37,200 miles.
So what multi-path route would add those miles?

-Mike.

Hi Mike - The OP said 1/10 to 1/20 sec. That works out to 18,600 to 9,300 miles..... The earth's diameter is ~24,900 miles. Madrid to Chicago is ~4,100 miles.

Short Path Delay is ~ 4,100/186,000 sec. = 0.022 sec.

Long Path Delay is ~ 20,800/186,000 sec. = 0.118 sec.

Difference is .0898 sec. which is 1/11.14 seconds.

Smack Dab in the time frame he is claiming.....

Short and Long Path are being heard.....

Grover