Topband: Interesting Propagation Anomaly 5/26/02 - 0030z

[K1ZM@aol.com]

Hi Gang

Has anyone ever seen this one before on 160M?  And, if so, what is the 
propagation mechanism at work here?

I was operating in CQ WPX CW last Saturday night up at VY2 and at about 0000z 
I heard ES9C calling CQ on about 1833 I think it was.

Signals were about 549 - weak but good copy on a 45 degree bearing.  I called 
several times with absolutely no reply.

I came back some time later to the ES9's QRG and, for some reason, I switched 
the antenna EAST -  with signals improving to 559 - maybe a bit better.

I tried SOUTH and ES9C was now 569/579.  At first I thought I was confused 
and checked everything to be sure of myself.  Sure enough, he was pee-weak at 
45 degrees and 579 from almost due SOUTH.

I called him again beaming due SOUTH and worked him after a few passes back 
and forth.  I was hearing him fine - he was hearing me not as well.

After the contest, I was told that ES9C is using a delta loop xmit antenna.  
I am using a directional vertical array for both XMIT and RX.

There is no doubt of the heading on this one at my end - almost due SOUTH.

I understand that at about 0054z W8JI spotted ES9C and noted it was a SE skew 
path on Rx at Tom's place.  I was seeing it due South but perhaps that was 
because I was further North.

I can hazard a guess as to the mechanism here - but it is only a guess:

1) ES9C was most probably in some form of twilight on his end.  BETTER 
propagation existed along a heading into more full darknes - perhaps 
accounting for the skew South.

2) What is most unclear to me is that RN2AF (RW2F) was up on 1835 at the time 
and was coming in 569 on a TRUE BEARING.  When I switched SOUTH on him, he 
faded way down.

3) A look at the map shows that it is indeed possible for RW2F to have been 
into more complete darkness than ES9C - thus a direct path for him and the 
SOUTHERN skew for ES9C.

No doubt about it, this is the first time that I have ever seen this happen 
on Topband - and it seemed most odd for the mechanism to be so different in 
two European locations in (relatively) close proximity to one another.

Wonder if anyone has seen this one before?

160M is surely a strange band!

73 and good dx

JEFF

K1ZM@aol.com