Topband: V84SAA - Part IV - Some Rx Analysis and Final Report

k1zm at aol.com k1zm at aol.com
Fri Feb 22 01:49:41 EST 2019


Hi Gang
This will probably be the last from me because there is not too much more to add to the mix - but I would like to comment on the progression of our RX antennas - and some theories why we could not hear well at our SR into the NA east coast via LP after 10 February.
In order to do this, I will explain what we started with, then what we migrated to and finally what we ended up with for RX antennas while there.
Days 1/2/3
1) We had two Rx antennas and the xmit vertical at the shoreline.  All of these antennas were on the beach about 500 feet from our operating tent.  For EU we had a 1000 ft beverage installed by S55M - and it was aimed at about 035 degrees - and it ran parallel over the sand about 100 feet off the ocean and parallel to it.
Before going to V84 I was told by quite a few "experts" that a beverage does not work when run over sand and next to salt water.Let me say here and now that this "wive's tale" is utter NONSENSE - so pls do not believe it for a second. I personally have used such an antenna at 7O6T in 2012 and also here on Cape Cod in 1998 when K1HTV and W4ZV were here for a CQ 160m CW contest.
Bill and Rich both were ecstatic about how well the BEACH BEVERAGE could hear Eu - even though it was only 600 ft long.
So - my take on our NA Rx  capability on the short path was that it worked and worked well.
Later in the week Adi extended it by another 1000 feet - so we had a 2000 footer aimed NE for the last 3 nights at SUNSET our time.
2) For the first three days we had a second RX antenna which was a DHDL which was pointed at about 330 degrees to EU on the short path that way.  Eu signals were LOUD and we worked TONS of them each night from 1500z-2145z or so.  About 2200z each night we started looking for VO/VE1/VE9 and W1-W3 callers - our SR was at 2237z or so - which means we had a decent darkness overlap into this region.
As I noted before, we had a single feedline for these two Rx antennas that was SHARED.  We started on the beverage from 1000z - 1500z (which is about VE7 SR time) and then went out with a flashlight and swapped the feedline over to the DHDL aimed at EU for the EU run from 1500z-2145z or so each night.
The DHDL was aimed to the NW and one end of it was close to the ocean.  We were able to hear EU with no issues - the pileups were HUGE and never stopped . In fact Eu was calling all the time even while we were attempting to work NA from 2200z-2237z - despite the fact that we chose to look for NA stations on 1805.5 qsx 1808.5.  The occasional JA also drifted down below 1810 khz - but, for the most part, we were able to focus on what we were trying to work - which was NA.  Now and then we would hear "JA UP"  or "Up 5" and this meant it was either a JA looking for us or an EU who had not yet cracked the pile.  Pls note that 2200z is still PRIME time into EU and JA signals are still loud on 160m even after their local SR.  One time I was called a LID and sent QFU by an impatient caller.  We knew this was going to happen but honestly - after 6 hours into EU and JA each night - we felt it was only right to focus on the NA SS and SR windows when it was our ONLY chance to hear and work NA during very short windows and having a mostly clear Rx freq devoid of S9 callers allowed us to perhaps hear NA - at SS and at SR.
I SHOULD NOTE THAT WHEN WE HEARD AND WORKED IN NEW ENGLAND (W1NA and N1DG et al) we were listening on our EU DHDL - which was all we had except for our Xmit antenna.  In retrospect we should have stayed with this combination.  What we were doing was to use an S55M splitter on the DHDL - (and on the NA BEV when the coax was hooked to that antenna) - and the splitter routed the signals both to 80 and 160m.  So each of us had our own xmit antenna when Krassy was on 80m and I had my own 160M xmit antenna sitting next to him for 160M operations.  Thus for the first few days were sharing the BEV and EU DHDL using a single splitter.  Again, this worked and worked well.
THE VK situation:
On night 3, Adrian KO8SCA came by and told me that the VK contingent was most unhappy with us because we were BOOMING down there yet I could barely hear them.  I copied partial calls for at least an hour - logging only perhaps 2-3 of them.   So what we did was add a SECOND DHDL on the beach aimed initially at 240 degrees.  This antenna was fed using a second RX feedline - and Adi modified the single splitter by adding a second one.  So starting on day 4 we had three RX antennas on two feedlines.  Each splitter had two outputs - one for 80m Rx and one for 160M Rx - and these were routed to two DAIWA 2 way coax switches.  Krassy and I could individually select which of the two RX antennas were available to listen on  - and the wiring of these systems was checked and double checked - it looked fine to me.
So now each op could do this:
a) Listen on the XMIT antenna - by selecting it from the menu on the ICOM 7610 radio
b) Listen at 1015z on either the NA beverage - or switch to the 240 degree SECOND DHDL.
And at 1500z when we swapped the first feedline we would have this from 1500z - 2237z at our SR
a) Xmit antenna
b) EU DHDL
c) 240 degree SECOND DHDL

In theory this meant that at our SR time for LP NA - we would now have two choices:
a) The original DHDL aimed at EU
b) the SECOND DHDL aimed at 240 degrees
c) the xmit antenna (usually not a good choice!)
Having made this change - we now could hear our VK friends and worked quite a few of them using the SECOND DHDL aimed at 240 degrees.
We also had what we thought was a better chance to hear NA LP because we could now listen over EU to W1 or to the SW at 240 degrees on the LP route over Africa to W1 LP.
Some observations:
Here is where I think we made a mistake because my recollection is that from night 5 to the end of our Dxpedition, EU was never as loud as it had been previous to these RX changes.  We thought it was changed condx - but now I am not so sure.
Also in that we never heard NA as loud as previously leads me to suspect some issue perhaps in the modified splitter arrangement (but I had Adi check it for me repeatedly) - so who knows?  Adi is a superb technical engineer and I have to assume he installed this in textbook fashion - but we will never know - HI

On the last several nights - we rerouted the 2ND DHDL to the SE at about 150 degrees - in the hopes of some LONGPATH into NA at our sunset opening of 1015z to 1100z (approximately)  At these times we had choices between the 2000 ft beverage aimed at the shortpath 035 degrees AND the Rerouted DHDL aimed at 150 degrees for NA longpath.
This combination really did not change our SUNSET results - it remained a 30 min window to NA from 1030z- 1100z each evening.  We finally did manage a few W8's and W9's I think - but no additional W1-W3 folks.  W4 was still in there - and the W5/6/7 - but no matter what we did, we could not hear the NE on the shortpath - except for NO3M.
So we again took another tack for the last 2 nights of our operation.
We rerouted the 2nd DHDL again to a new heading of 200 degrees which more approximated the NA W1 region (better than 240 for sure!)  This was intended to help perhaps on the W1 longpath.  In this configuration at our SR we could choose between these Rx antennas:
a) the EU DHDL aimed at 330 degrees
b) the 2nd DHDL aimed at 200 degrees
c) the xmit antenna.
Krassy on 80m had the same choices on his ICOM 7610.
For what it is worth - none of these changes made any real difference for us the last week on the W1 LP opening at our SR peak - meaning 2145z - 2237z.  I never again heard W1 on the LP as loud as I did when W1NA and N1DG were worked on Feb 9th & 10 I think..
However, on our 2nd to last night - due to some radio swapping during the day - Krassy and I operated together from the 160m position with split headphones on 80m CW - around 3505 I think - and we listened on ONE of these two DHDL's (I cannot recall which one) and had a good run into W1 from about 2215z - 2240z working VE9AA/W1FV/W1QS/W3BGN/WT3Q and quite a few others.
So the final attempt at LP RX at our SR did seem to work on 80M - but I do recall that signals were relatively weak.  When the W1 NA path closed - we hung in there for another 15 mins and about 5 PY stations called in at RST579-599 which came somewhat as a surprise to us both.  NA had closed yet SA was LOUD around 2245-2250z.  Go figure.

SOME LESSONS learned:  Pls note these are just my personal opinions - this is not HARD NEWS - it is COMMENTARY!  And I have strong opinions about many things - HI!
1) When on an expedition it is pretty chaotic all the time.  Various operators use the radios during the day on OTHER BANDS.This means when I returned to 160m each evening - I had to change quite a few things (including menu settings and antenna selections on a radio that is not one I knew how to use very well - this made it a challenge to be SURE everything was optimally setup each time I came to get on 160m at SS again.  Many years ago operating Multi-multi at W1ZM - my elmer Gerry Scarano advised me "Never make changes in the middle of a MM contest - it is a really bad idea".  I have always remembered that advice.....
But at the same time, I also must recognize that this was  a TEAM OPERATION and you have to go with the flow!
2) There are also dynamic changes that take -place on an expedition - almost every day.  Some ops want to go to FT8 - others want to make special efforts at SR to work into South America - and these too must be allowed.

So what we end up with is a very DYNAMIC and SOMETIMES CHAOTIC environment - and this makes it quite a challenge to keep one's eye on the prize.
(At VY2ZM over the years, I have hosted quite a few guest ops - and each time, I tell them (politely in advance) that I do not make operator preference changes in my station -   either you use it as it exists - or not at all.  Some requests have included running a different logging program installed the day of the contest (BAD IDEA!) - or moving monitors around and rewiring things on the day of the contest.
Also a really bad idea.
But on an expedition, you cannot  control everything at a given position - even though you may wish to do so.  All you can do is try to get back in the game each time you sit down in the chair -  and do your best - which is what I personally tried to do each time I sat down at the 160m position at our SS and SR NA times.

Final notes:

Thanks to all of you for looking out for us on Topband - glad we logged many of you if not all - the pleasure was all ours - and I also want to thank all of those who have written saying we did a good job out there.  It means alot to me and to Krassy who bankrolled much of the cost of this one for you guys.
I also am sorry I could not hear W1-W3 on the longpath at our SR for the final days we were out there.  I do NOT believe in ONE-WAY LP propagation - if you guys could hear us 559-569 on some days - we COULD and SHOULD have heard YOU.  At this point, we just do not know why that was - unless it was just condx - but I do not think so - we will have to do better next time - HI
Cu on the next one - Where do we go from here?  HI HI - with apologies to OH2BH!
73 JEFF   K1ZM/VY2ZM








Jeff BriggsDXing on the Edge: The Thrill of 160 Meters Available worldwide through BookBaby, Array Solutions, DX Engineering, Radio Society of Great Britain, & Amazon
















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