Radio: it's not just a hobby, it's a way of life

Current Operating Frequency and Mode

OFF AIR; QRT Thursday night but back Friday morning by 1100z

Path between Australia and North America was active for several stations including VK3HP –> WH2XCR; WG2XKA –> DL4RAJ for sole trans-Atlantic report; Daytime reports and evening JT9 at WG2XSV

– Posted in: 630 Meter Daily Reports, 630 Meters

The band was much noisier during this session and while there were many reports, S/N was reduced from previous sessions, at least here at my station in Texas.  There was no shortage of reports on the Pacific path and a single report on the Atlantic path.

Geomagnetic conditions are generally improved, at least at lower latitudes, and the Bz continues to point to the North for the most part but solar wind velocities continue to be elevated above 400 km/s.  The Australian and Kyoto DST continue to be at disturbed levels.

planetary-k-index 041616


Kyoto DST 041616


Australia 041616


Larry, W7IUV / WH2XGP, reported that he decoded seven WSPR stations and was decoded by 34 unique stations, including VK4YB.

WH2XGP VK4YB 041616

WH2XGP, as reported by VK4YB

Larry also noted the almost daily appearance of a daytime path to N6SKM, a distance of 1080 km.  For much of the late winter, the persistent daytime path to WB0VAK was open, at 2075 km.  This band is quite serviceable during the daytime if you pick and choose your battles carefully.

Ken, K5DNL / WG2XXM, reported that he decoded six WSPR stations and was decoded by 38 unique stations, including 52 reports from WH2XCR, best at -9 dB S/N, and 119 reports from VE7SL, best at +1 dB S/N.

Phil, VE3CIQ, sent the following report for his session:

VE3CIQ 041616b

VE3CIQ 041616a

VE3CIQ session WSPR activtiy


Steve, VE7SL, reported Roger, VK4YB, again during this session.  Expect a JT9 QSO between these two in the future as its obvious the path exists.  Steve provided an extensive report on Roger’s operation on his blog.

VK4YB VE7SL 041616

VK4YB, as reported by VE7SL


Neil, W0YSE/7 / WG2XSV, reported that daytime decodes of his 1W ERP signal continued to be excellent at high noon with reports from VE7SL and VE7BDQ at -20 dB and -22 dB S/N, respectively.  During the evening, Neil operated a JT9 beacon with reports from Toby, VE7CNF, improving from -24 dB S/N at 0216z to -10 dB S/N at 0410z.  Neil also reported Toby at -11 dB S/N at 0410z.  He also provided the following statistics and comments for his WSPR session:

WG2XSV 041616c

WSPR activity was at 63 MF WSPR stations during the evening in North America.  Regional and continental WSPR breakdowns follow:

NA 041616

North American 24-hour WSPR activity


EU 041616

European 24-hour WSPR activity


JA 041616

Japanese 24-hour WSPR activity


VK 041616

Australian 24-hour WSPR activity


No reports were found for the trans-African path.  UA0SNV was present from Asiatic Russia but no reports were uploaded to the WSPRnet database.

John, WA3ETD / WG2XKA, received the only trans-Atlantic report, once again, for the session from Clemens, DL4RAJ.

WG2XKA DL4RAJ 041616

WG2XKA, as reported by DL4RAJ


Eden, ZF1EJ, reported stations across the US during this session.

ZF1EJ 041616

ZF1EJ 24-hour WSPR activity


Laurence, KL7L / WE2XPQ, reports that he was only receiving during this session and conditions continue to be very poor from Alaska.  In spite of poor conditions, he did receive Roger, VK4YB.

WE2XPQ 041616

WE2XPQ 24-hour WSPR activity


VK4YB WE2XPQ 041616

VK4YB, as reported by WE2XPQ


WH2XCR WE2XPQ 041616

WH2XCR WE2XPQ 041616b

WH2XCR, as reported by WE2XPQ


John, VK2XGJ, reported very noisy conditions in Australia but that did not stop Merv, K9FD/KH6 / WH2XCR, from being decoded and providing decodes for several stations including VK3HP.  The path to the eastern US was very good as well, with reports for WH2XZO and reports by WG2XJM.

WH2XCR 041616

WH2XCR 24-hour WSPR activity


WH2XCR VK2XGJ 041616

WH2XCR, as reported by VK2XGJ


WH2XCR VK4YB 041616

WH2XCR, as reported by VK4YB


In Australia,  Phil, VK3ELV, Roger, VK4YB, and Grant,VK3HP, received reports from WH2XCR.  Phil  received reports from a number of stations in Japan through the session as well:

VK3HP WH2XCR 041616

VK3HP, as reported by WH2XCR


VK4YB WH2XCr 041616

VK4YB, as reported by WH2XCR


VK3ELV WH2XCR 041616

VK3ELV, as reported by WH2XCR


VK3ELV 7L1RLL4 041616

VK3ELV, as reported by 7L1RLL_4


VK3ELV JA8SCD5 041616

VK3ELV, as reported by JA8SCD5


VK3ELV JA8SCD 041616

VK3ELV, as reported by JA8SCD


VK3ELV JH1INM 041616

VK3ELV, as reported by JH1INM


VK3ELV JH3XCU 041616

VK3ELV, as reported by JH3XCU



“Today, we consider 630m Pacific paths that join the Southern Hemisphere with Northern Hemisphere latitudes less northerly than those Europe occupies.

 Look first at the graphical illustration. It sets astride four categories of 2015-16 inter-hemispheric paths, those between:

  • North America and Australia (purple)~12500km
  • UK/Europe and Reunion Island FR5 (brown) ~7500 to ~9500km
  • Australia and Japan (red) ~8000km.
  • Australia and Hawaii (navy blue)~7600km to ~8700km
  • Hawaii and Japan (light blue, non-equatorial) ~6300km

What do these results, accumulated by the persistence of so many 630m amateur and experimental stations, tell us?

At first glance, the graphs of number of decodes for the paths seem just an uncorrelated jumble.  Perhaps they’re just a Rorschach test – eliciting whatever perceptions to which our minds are predisposed.

The VK-JA and HI-VK paths appear to lack both the monthly periodicity of EU-FR5 and the fortnightly periodicity of HI-JA.

I’ve included the HI-JA graph, even though it’s Northern Hemisphere only, to complete a cross-Pacific triangle.  Comparison of HI-JA with VK-JA helps factor out variations due to JA storms and JA station operations. Also, comparison of  HI-VK and VK-JA helps factor out variations in VK tx station operations. (Decode numbers for HI-VK include VK to HI.)

For instance, HI-JA decode peaks have declined in 2016, while VK-JA peaks have become stronger.  Evidently, this is not an effect of JA storms and RX operations.  VK3ELV is mostly responsible for VK-JA transmissions throughout the season, so a change in number of VK tx stations is not the cause of the stronger VK-JA peaks.

Instead, the all-Northern Hemisphere HI-JA explains why its tallest peaks happened in fall-winter’s longer nights. By contrast, VK-JA, HI-VK, and N.Am-VK have benefited more recently. That’s thanks to the beneficial compromise that VK early fall strikes with early spring in JA, HI and N.Am. around equinox in both hemispheres.

Turning to the non-periodic jumble of activity represented by the HI-VK and VK-JA graphs, I suggest the astrophysical and geophysical dynamics of each of the two hemispheres are in play.  The desire for a single explanation based on Principle of Least-Mystery collides with 1) Explanation by Pure Randomness and 2) a fallacy that All Peaks Have Same Explanation.  Precisely because two hemispheres are involved, the results probably conflate two different sets of hemispheric dynamics.

Also, any particular HI-VK graph aggregates Australia paths involving Victoria, New South Wales, and central Queensland. Diversity of paths is surely scrambling the HI-VK numbers somewhat. However, I’m deliberately aggregating those diverse paths in both directions to assess overall HI-VK effects.

Now let’s compare the rather-different-looking respective sequences of HI-VK (bottom), VK-JA (red), and N.Am-VK (purple, top). HI-VK and VK-JA have shown steady 2016 activity, albeit punctuated. Meanwhile, N.Am.-VK mostly amounts to a small cluster in late March and early April.  Why the difference?

I appeal to the longer path length of N.Am.-VK. Recall that numbers of decodes sharply decrease with lower SNRs, and lower SNRs typically result from longer path length. Mentally make the graphs of HI-VK and VK-JA decodes sink lower and lower so that only their higher peaks remain. What remains is a bit of activity in the first part of February and then the more recent burst we’ve seen.  That describes the N.Am.-VK path activity!

In short, the HI-VK, VK-JA, and N.Am-VK paths are subject to similar overall dynamics in my view. Those dynamics are scrambled up geophysically between two hemispheres.  I neglect to explain the evident contrast with the qualitatively different EU-FR5 cross-equatorial periodicity of the remarkable three months Oct. 30-Jan. 30. Let that interesting EU-FR5 question await a full season’s worth of information.

What can your experience and horse sense tell us about these world-scale propagation questions? Let us know!”

W5EST 041616

Additions, corrections, clarifications, etc?  Send me a message on the Contact page or directly to KB5NJD <at> gmail dot (com)!