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

Band conditions and propagation see significant improvements after a few sub-par sessions

– Posted in: 630 Meter Daily Reports, 630 Meters

What a difference a day makes!  At my station here in Texas the band was as quiet as ever seen in Winter with coast to coast reports, many at CW levels.  and even reception reports of John, VE7BDQ, and Brian, W1IR / WG2XPJ, signals that have been absent from my WSPR log for a few weeks as we have weathered numerous storms.

Geomagnetic activity was variable, with elevated periods during the session but generally quiet conditions.  The Bz has generally tended to the South during the session and solar wind velocity has been in excess of 400 km/s.  DST levels continue to suggest poor band conditions.  Experimental evidence, at least at lower-middle latitudes, suggests otherwise.

planetary-k-index 050616


Kyoto DST 050616


Australia 050616


Phil, VE3CIQ, also experienced an improved session and offers these statistics and map of his activity.

VE3CIQ 050616a


VE3CIQ 050616b

VE3CIQ session WSPR activity


John, WA3ETD / WG2XKA, experienced improved conditions as well, including an open transcontinental path to WH2XGP.

WG2XKA 050616a


WG2XKA 050616b

WG2XKA session WSPR activity


Larry, W7IUV / WH2XGP, has recently been received at my station with some very nice signal levels near my local sunrise but Larry reports that during this session the SWR protection tripped due to high winds and he was QRT.

Neil, W0YSE/7 / WG2XSV, also experienced a better session and made some significant performance improvements with his amplifier.  Neil provided the following statistics and comments:

WG2XSV 050616


David, G0MRF, emailed with a report of his new prototype PA that he is developing for next season and offers the following details and picture:

G0MRF 050616a


David continues in an additional email:

G0MRF 050616b


Its never too early to start preparing for the next season!

G0MRF PA 050616

G0MRF prototype PA


Regional and continental WSPR breakdowns follow:

NA 050616

North American 24-hour WSPR activity


EU 050616

European 24-hour WSPR activity


JA 050616

Japanese 24-hour WSPR activity


There were no WSPR reports from the trans-Atlantic or trans-African paths.  UA0SNV was present during the session but no reports were found in the WSPRnet database.

Storms that were plaguing the south eastern US have now moved across the Cayman Islands allowing Eden, ZF1EJ, to provide reports for my station over night.

ZF1EJ 050616

ZF1EJ 24-hour WSPR activity


Laurence, KL7L / WE2XPQ, reported three WSPR stations during this session, including VE7BDQ, WG2XSV, and WH2XCR.

WE2XPQ 050616

WE2XPQ 24-hour WSPR activity


WH2XCR WE2XPQ 050616

WH2XCR, as reported by WE2XPQ


WG2XSV WE2XPQ 050616

WG2XSV, as reported by WE2XPQ


VE7BDQ WE2XPQ 050616

VE7BDQ, as reported by WE2XPQ


Merv, K9FD/KH6 / WH2XCR, continues to see strong openings to Australia as well as the West coast of North America.  I am a little surprised that Merv and I did not reciprocate reports during this session as I made an effort to switch to the western RX antenna in the middle of the night in Texas.

WH2XCr 050616

WH2XCR 24-hour WSPR activity


WH2XCR VK3ELV 050616

WH2XCR, as reported by VK3ELV


WH2XCR VK2DDI 050616

WH2XCR, as reported by VK2DDI


WH2XCr VK4YB 050616

WH2XCR, as reported by VK4YB


WH2XCr VK2XGJ 050616

WH2XCR, as reported by VK2XGJ


VK4YB WH2XCR 050616

VK4YB, as reported by WH2XCR


VK3ELV WH2XCR 050616

VK3ELV, as reported by WH2XCR


Jim, W5EST, presents this discussion based on resent email exchanges that he and I had, entitled, “LACK OF XCR-JA: A 630M MYSTERY?”:

“Northern hemisphere spring season 630m long paths to and from Merv’s WH2XCR (Molokai) prompted this dialog yesterday.

Jim W5EST:  

Hi John (XIQ), I’ve been thinking about the Japan mystery. (May 5 blog, scroll 1/3)  Feel free to educate.

We are a month past spring equinox in the N. Hemisphere so it’s reasonable both that transatlantic (TA) has declined and also Hawaii-JA as well.  See also the April 13 blog content with KH6-JA seasonal graph re this. (April 12, 14, 16 too.)

Regarding no VK3ELV-JA decodes May 5, I think it’s probable a storm system raised the band noise enough to cut that path off. The storm is shown on worldwide lightning locator network wwlln advancing toward Kyushu since 0500z from the SW.

VK-JA was -27/-28dB level sparsely May 4 so that’s proving less a seasonal matter than KH6-JA.  Since VK3ELV is well into fall at a more extreme southern latitude than Hawaii, the VK-KH6 season is continuing nicely.


Recognizing that the path between KH6 and JA is longer than KH6 and Texas, I guess looking at the map has me considering why the salt water path is significantly worse than the path across a significant amount of land and salt water.  Of course we have seen the impact of even small pieces of land combined with salt water paths in the variations in reports from VE7BDQ and VE7SL. So I guess it is just a different situation…A comparable distance (within a 1000 miles or so) to ZF1EJ from KH6 has also not yielded reports in a while.  Merv indicates this E/W path is challenging for him on 160m…it probably figures in…

Jim W5EST:

See TABLE, especially “REFdB” and “WINDOW” to compare paths. 1w XCR-xiq 6023km last happened April 25.  There’s been stormy wx to blank most of the XIQ rx nights since then.  Ground reflection not helping on 3 hop higher angle long path.  But you may still have some XCR-xiq potential with your excellent rx antenna. I hope Merv XCR gets through to XIQ sometime tonight or next couple of clear nights.

Favorably for you, 2w XIQ-xcr seem to be steady thru last night so that’s a good sign for Merv into xiq, even though Merv has 3dB tx power disadvantage compared your tx power.

1w XCR-ve7bdq is a short 2-hop 4320km path with a single salt water surface reflection. XCR-ve7sl reception was active May 2 and no ve7sl receptions of anybody have occurred since then as far as I can tell.  There should be plenty of life left in XCR-B.C. path.

1w XCR-zf1ej last happened April 15 and is an interesting case, yes–7842km means three 2610km near-horizon hops with a ground reflection in XE-land.  Given N. Hemisphere spring as well, that makes sense it would fade out.

Last gasp for 1w XCR-jh3xcu also came April 15.  Yes, that fadeout is interesting as you say, notwithstanding modest 1w XCR power level.  6285km is 3-hop all salt water at a bit more favorable higher angle for a 3-hop long path–3.3°.

Your question makes sense–why hasn’t XCR-ja had longer life than XCR-zf1ej.  Perhaps because nights at the higher JA latitude are shorter than for ZF1EJ after spring equinox?


I keep wondering if the JA’s that hear well are using directional rx antennas and maybe just not listening to the east.  A few of those guys have websites that might have this info in Japanese… I didn’t see any pics to suggest directional antennas but one never knows.

Terminator in DX atlas through N.Am. sunrise SR shows we have lost a lot of night. Given that most of the “good stuff” doesn’t start until later and closes early, the short night is easy to see when looking at the width of the northern hemisphere darkness. [Nights now are shorter in JA but the path to JA is shorter than to ZF1, so JA vs ZF windows are nearly a wash.]

Anyway, it has been interesting and I just hope that everyone keeps on the air through summer– a lot of merit in being on the air year around.


JA             4/15    6285        3          0       0           0          6.3hr        3.3°
ZF1EJ      4/15     7842       3           0     -6        -7.9         6.0hr        0.5°
XJMtx     4/10     7413       3           7      -6       -0.4         5.3hr        1.2°
XJMrx     4/22     7413       3           0      -6       -7.4         5.3hr        1.2°
XZOtx     4/16     7357       3           3      -6       -4.4         5.5hr        1.3°
KU4XR   4/08     7174       3           0      -6       -7.1         5.7hr        1.6°
SWL/k9   4/22     6844       3           0      -6       -6.7         5.7hr        2.2°
XIQtx       5/05    6023       3           3      -6       -2.6         6.6hr        3.9°         Yes
XIQrx      4/25     6023       3           0     -6        -5.6         6.6hr        3.9°         Yes>4/25
XXMtx    4/28     6007       3           7     -6       +1.4         6.6hr        3.9°         Off >4/28
XXMrx    4/25     6007      3            0     -6       -5.6          6.6hr        3.9°         Yes>4/25
XPQtx     5/04     4540      2           10    +5    +17.8          8.6hr        2.3°
XPQrx     5/06     4540      2            0     +5      +7.8          8.6hr        2.3°
XXPtx     4/21     4534       2          10    +5    +18.4          7.6hr        2.3°        Off>4/21
XGPtx     5/05     4434       2          10    +5    +18.0          7.6hr        2.6°
XGPrx     5/06     4434       2           0     +5      +8.0          7.6hr        2.6°
‘BDQtx   5/06      4320      2           7     +5    +15.3          7.7hr        2.7°
‘BDQrx   5/06     4320       2           0     +5      +8.3          7.7hr        2.7°
VE7SLrx 5/02     4295       2           0     +5      +8.3          7.7hr        3.0°


Notes: “Path” identifies station at the other end from XCR. “Latest” is 2016 date of last decode on the path.  KM is distance. “EHops” is ceil[KM/(Max 2730km/hop)]. “Pwr” is dB difference of TX station over XCR 1w.  “REFdB” computes Path Advantage by reference to XCR-ja path:

REFdB=Pwr +RefldB +10log10[(KM(ja) /KM(Path)]2

RefldB= -GndRefl6dB+(3-EHops)6dB first assumes an extra 6dB per ground reflection.  Then 5dB/hop combined salt water reflection loss with E-layer reflection loss compares paths with fewer hops than the 3 hops to Japan. (Path Advantage omits peak SNRs of Propagation Potential Difference Jan. 31, this blog.) Substitute more accurate loss numbers if you wish to revise the table.  “Angle” informationally estimates path elevation angle assuming 150km E layer:

ANGLE ~=  56.0° [0.02354/θ  – 0.5118 θ] where θ = “KM”/(2xEHOPSx6371km)

Earth radius is 6371km.  “Window” is common darkness duration in hours for the path May 7, 2016, between its west end sunset and its east end sunrise.  “Lat.” is northernmost latitude reached by the path. “Storms” signifies known persistent storm activity near RX several days in the last two weeks or TX QRT. XCR-XKA is untabulated–showed no database entries either direction, and XCR-XZOrx eastbound has no database entries either. Please excuse any omissions.”


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