Showing posts with label WSJT-X. Show all posts
Showing posts with label WSJT-X. Show all posts

Saturday, March 11, 2017

Propagation Sanity Check

This morning we received an email from Finland!  It's always nice to hear from our "neighbors" across the north pole.  I know we share a common bond when it comes to tough propagation.

Hello, Sirs.
It is quite foolish to ignore JT65 spotter on.
The whole of Europe called on you.

None of the answer does not come from there.

OH4SS, Matti

I was certainly sorry to miss the opening.  

So it would seem Matti is implying one shouldn't run JT65 spots to PSK Reporter if not in the shack. Now that's an interesting point of view, and one I haven't encountered before.  I think we have a little disagreement here with Matti, but maybe there are others out there who feel the same way. 

"Foolish"?  Let me explain my rationale.

Followers of the blog -- are there any? -- will know there are special challenges the ionosphere lays on us in the high latitudes.  What they teach you in radio school about propagation being basically reciprocal is total nonsense above 60 degrees or so.  It's actually hard to figure out when openings may occur.  The second element to this puzzle besides geomagnetic instabilities is the rapidly changing daylight in the Far North.  In Fairbanks, daylight changes 6-7 minutes per day throughout much of the year.  That has huge implications for HF, as one week is literally completely different from the next.

Sooooo...here at KL2R we make frequent use of spotting software and other tools to monitor the bands. That includes CW Skimmer reporting to RBN and WSJT-X reporting to PSK Reporter.  The data is helpful to other hams who are anxious to see when the bands are open to Alaska.  What's not to like?

The other reason we frequently run receivers and spotting software when the shack is unattended is to gather data for serious technical analyses.  The data sets are useful for comparing station performance, for instance.  JT65 actually yields quantitative results on received signal-to-noise ratios from various locations.  We can compare, say, AL7ID just a few miles away.  Even better, years of study have clearly demonstrated the myth of reciprocal propagation.  Approximately 80% of the time, the KL2R signal SNR will be about 6-10 dB worse at the remote station than received here.  What that means in practical terms is that when we receive JT65 at around -15 dB (good by most standards), the other station is likely to receive us at very marginal levels, if at all.  So there you have it.

Finally, let me just say presence on PSK Reporter is not the same as a call for CQ.  The spotting network does not substitute for actual RF.  So who's "foolish"?  I suggest those who would call a station without hearing their signal.  Whatever the mode, many Europeans have a bad habit of throwing out their callsign into the ether in the hopes the DX will log them, like a message in a bottle. It's remarkable that within hours of working a pileup I will get requests by email, like "Please tell me if I worked you."  Seriously?  If I worked you, you would know it.

Monday, September 23, 2013

Whispering on WARC

Of late I have been focusing a bit on working Europe on the WARC bands to close the gap on Worked All Europe first class award (WAE I).  I have also boosted the numbers slightly on 40m. JT65 has made it possible to work pretty reliably into EU most days and evenings on 30 or 17. While experimenting with WSJT-X 1.1 this weekend, I finally saw Cliff VK2CCJ working KH6OO on JT9 in the 12m band.  We eventually connected with this exciting new mode.

Wednesday, September 18, 2013

The Summer Wraps Up

Snow today for the first time since May 23. It was a short summer.  Leaves and ground cover are in full blaze of yellow, orange, and red.  The contrast of snow on dark spruce and low-hanging clouds ringing the hills made for a dramatic landscape.  Alas, antenna season wanes quickly.  A 40 meter vertical project hangs in the balance.

Living for much of the summer under threat of wildfires, the station has been largely pieced back together.  A full multi-2 is nearly 100% functional.

The rig has been on quite a bit lately monitoring JT-65A on the low bands.  I have been using JT65-HF for ages, but recently found WSJT-X 1.1 works faster and decodes more effectively on my slow XP PC.

John AL7ID, who lives just a few miles east of KL2R, put up a full-size 160m loop around his property.  Comparisons on the various bands has been interesting.  The 30m band has outstanding worldwide coverage much of the day now, and 40 has had some strong nights for DX.  A61BK was even heard here at midday on a dipole, which was totally anomalous.  160 yields the Lower 48 as sunrise moves across the US, and 80 has been marginal most evenings.

Nearly two weeks ago I was in Anchorage re-building KL7SB's shack with a complete Elecraft K3 line and Microham MK2R+ SO2R box.  I will do it again in a few days.  Given the uncertainty of the 40m project at home, I might as well do something useful.