Monday, January 19, 2015


I worked them 10 minutes before sundown local.  (the above was taken about an hour later)  The pileup was amazing

Very very dense RF.  The SDR/CWskimmer combo was invaluable in analyzing the pileup.  eventually he moved down the pileup to about 1.5 khz above his transmit freq where the signals were sparse and that is where I worked him.  All those guys who were 8 khz up the band were never in the running.  The opposite happened to me last night.  I spent 3 hours trying to work him on 30M but I didn't have any propagation to EU or AS and last night I was transmitting up 2-3 and he was listening up 7, so no way last night.  the panfall and skimmerfall did not help at all.  When I realized he was up 7, the terminator had overflown his head and he soon faded into the noise of day light.

If you look closely at the way I have the radio set up I am listening to EP6T on the B vfo and transmitting on the A vfo.  I do this because click tuning on skimmer causes VFO A to change, so it makes skipping around the pileup much more ergonomic.  Once I get the DX tuned in perfectly I set the lock on vfo B so I don't click myself off freq at the wrong time. and set the TX to VFO A.  With the Flex 6300 all of the controls related to each "slice" such as DSP, AGC-T volume AGC RIT etc are available on both vfo flags so it's super easy to fine tune either vfo's properties.  I also run my FlexControl tuning through DDUTIL v3.0 because its very easy to switch between VFO A and VFO B

simply by pressing the knob.  Another advantage of this single-panadapter-2-VFO implementation is it's quick to deploy.  The disadvantage is the decoder aspect of Skimmer is lost since the decoder goes with VFO A and the DX station is on VFO B.  Not a big loss since I copy in my head anyway.   

There is another way to deploy SSDR for split DX ops and that is to use slices!

As you can see now panadapters are independent and there are 2 skimmers.  With 2 skimmers the decode function of skimmer works in each skimmerfall so that aspect is preserved.  In addition each skimmer decodes independently so the information in each skimmer is not a mirror of the other.  This means if the DX is sending a callsign and I want to tail end I have a greater opportunity to discover where that station is in the pileup and click tune to that freq.  I always set up the skimmer streams to match horizontally.  My transmitter slice is always B so even if see the call in slice A it's heartbeat quick to slip the mouse over to slice B and click to tail end a given station.  Skimmer does one more thing it repoerts out a decoded 599 as a red flag

with the most recent 599 as bold and bright red.  This is a big clue of where to tail end but not infallible.  There are a LOT of stations who think they are working the DX and sending 599 when they are not even in the ballpark.  Tracking 599's is a good way to discern where the DX is moving in the pileup.  Like bread crumbs you can pick out if he is moving up or down and try to insert yourself into where he is going to be listening next.  This is the technique I used tonight I saw him moving down and placed my transmitter at the next clear spot on the panadapter and 10 minutes to sundown he was in the log.  

Over the years it interesting to see how skimmer has changed working pileups.  The RF in the panfall and skimmerfall ball becomes much more dense as 599's are handed out.  So once again even skimmer use requires strategy.  On to 30M and 80M!!

73  W9OY

Got them on 30M at their sunrise!!  The panfall and skimmerfall did help but in a unique way.  Once again I had no propagation stateside.and EP6T was working NA.  He was had a nice signal and the band was really quiet.  Occasionally skimmer would decode a lone stateside callsign so there was some kind of backscatter poking a bit of stateside coherence through the noise.  This mode of propagation turned out to be quite useful.  I was relying on cluster spots to steer my transmit freq but these were inconsistent , up 2.7, up 3.8, who knows where he was listening.  The previous night while listening on 30M I noticed there were a trail of white spots on the pan up 7-10 khz, but I thought they were too far away to be in the pileup and I didn't want to QRM some joker calling CQ.  It turned out this was precisely where the DX was listening and the falling dots in the waterfall, were actually the pileup.   

Not to be fooled twice, watching the panfall I noticed occasional streams of white dots on 10.125 falling down the waterfall, streams that were maybe 50hz apart, consistent with a couple stations breaking the propagation induced radio silence.  The DX was on 10.123 (actually 10.122847, the Flex's filters are tight enough that if I tuned to 10.123000 I could not hear the DX).  It was clear from the way he was working stations he was pretty much hugging one freq on RX and up 2 seemed a logical choice so I started calling there and pretty soon he was in the log.  Once again SDR allowed me to peer into radio darkness and pull out a plumb.  

I have 2 SDR radios, a Anan100D and the Flex 6300.  Each has it's advantages.  When it comes to gleaning information from the panadapter the Flex wins hands down.  I swear it can hear under the noise.  Unfortunately I didn't think to take a pic.