Geomagnetic storm conditions finally showed their teeth overnight and while that may ultimately mean bad things for high latitude stations or paths that pass through high latitudes, we don’t seem much worse off yet. Trans-Atlantic openings were plentiful and the trans-African path between Europe and Reunion Island produced good results. Domestically, a few receiving stations produced big reports for stations in North America, particularly on the North / South Path. Activity was also very high and we even gained a new receiving station in KH6 who had a successful first outing. Pacific paths, which are often the loser when we see these storms manifest themselves early, continue to be very robust. Whether we observe big, late openings between KL7 to JA later this morning remains to be seen.
QRN was extremely low in North America although there were a few pockets of stormy weather that probably contained lightning and may have contributed to precipitation noise. I was surprised to find approaching storms this morning during my CW session but could not hear them on the air until shortly before QRTing, suggesting to me that the band may be very long and I was just not hearing the local weather that was producing pings on the lightning map 100 miles away.
The Kp peaked at 6 overnight and was slow to recover as solar wind is now reported above 700 km/s. The Bz has been variable although mostly pointing to the South. DST values have shown sharp decreases.
There were early reports that FR5ZX and ZS6KN had received one another on WSPR but it turned out to have occurred on 15-meters. Even so, the complicated path between Reunion Island and Europe produced results with DK7FC and EA5DOM making the very long haul. Details of those reports can be viewed here.
Luis, EA5DOM, reported that Ken, ZS6KN, continues to work to improve his local noise problems and is trying a variety antennas including a 160-meter dipole for receive.
Luis also reported good daytime propagation:
“I’m keeping Tx in WSPR over daylight due to the high geomagnetic activity in the last hours. We have got a G2 Kp6 and Kp5 level recently http://www.swpc.noaa.gov/communities/space-weather-enthusiastsThe decodes from G8HUH at 1430km have reached -1 !! :-O
2016-11-25 09:32 EA5DOM 0.475611 -1 0 IM98wn 1 G8HUH IO81mg 1430 352Lets see if this helps to get decodes even at 12 utc Last night was very good for high latitudes East<>West and also one decode from DK7FC at FR5ZX. I got some US decodes and FR5ZX being at 38º North latitude. 73 de Luis EA5DOM.”
“Not quite the previous session, but interesting. The PNW and west coast were underrepresented here. Rain forced TX shutdown at about 0900. However, both-way spots with WH2XCR continued for the second night, and DK7FC was spotted here. Noise levels continue to be reasonable considering the season.”
Doug, K4LY / WH2XZO, noticed the impact of the geomagnetic activity and offered these comments and statistics:
“Rising high latitude attenuation as marked by the increasing K and A indices, may have been the reason for reduced 630M results here, only 9 unique stations spotted and only 37 spotted by WH2XZO.”
Rick, W7RNB / WI2XJQ, reports continued wind and rain and slightly down conditions from recent sessions. He decoded eight WSPR stations and was decoded by 26 unique stations. Rick’s unique report details can be viewed here.
Trans-Pacific reports for this session are aggregated here.
Ward, K7PO / WH2XXP, received reports from 62 unique stations including JA1NQI-2, JA3TVF, JE1JDL, JH1INM, JH3XCU, VK2XGJ, and VK4YB.
Larry, W7IUV / WH2XGP, received reports from 53 unique stations including JA1NQI-2, JE1JDL, JH1INM, VK2XGJ, and two-way reports with VK4YB.
Roger, VK4YB, experienced a good session with reports from JA3TVF, JH1INM, VA7JX, VE7SL ZL2IK and provided reports to WH2XXP and shared two-way reports with WH2XGP, WH2XCR, and WE2XPQ.
Pete, ZL2IK, found success in spite of high noise and posted these comments on the VK/ZL 600m reflector:
“There was a very large front full of Thunderstorms in the NW Tasman last night about half way from my QTH in Northland and Norfolk Island, it played havoc with reception earlier in the night. I could see the tracks on the waterfall, but they were not decoding, because bits were missing from them due to the QRN.
However after 1200z things quietened down enough to get some good decodes from VK4YB and some excellent decodes from Jim ZL2BCG who is 655 km south of my QTH near the shaky bit of the South Island. (I can say that because my end of the Country doesn’t shake!) – Well done Roger and Jim.”
Neil, W0YSE/7 / WG2XSV, provided reports today via his IPhone, using an app called WSPR Watch. Neil indicates that he decoded WH2XZO using the E-probe and provided the following map and unique details for the session:
Mike, WA3TTS, continues to see good openings to the West and offers these comments and statistics:
“Another evening with a high number of WH2XCR decodes (36) best at -16, -31 minimum, and fairly even distribution in the SNR range….“
Mike provided these closing thoughts:
“I ran split IF for 630m and 2200m wspr2 on the NW EWE antenna overnight, which was much quieter than the NE direction which had high QRN levels. 172 WH2XND decodes and 17 WD2XES decodes overnight. 73 Mike wa3tts”
We were joined by a new receiving station in Hawaii – Terance, KH6L. Terance is new to WSPR and I had a chance to provide him with updated frequency information earlier this week. I am very happy to see that he had success in getting WSPR running and decoding stations during this session. Welcome aboard!
Vinny, DL6II, reports that this is another MF QSO party weekend in Europe, this time using QRSS modes:
Like many in the US, I was distracted by Thanksgiving meal activities with my family so I did not make it into the shack until later in the evening. There was no CW session in the evening. I was successful at starting WSPR around 2300z, however, and reports were quick to begin, even in full daylight. Also notable were the big reports from David, WB0VAK, who seemed to persistently report my signal and others with big, positive S/N values (+20 dB S/N here on a number of occasions and averages above +10 dB S/N). My first inclination was that he must have been using tight filters to artificially inflate S/N numbers but he was hearing a number of stations at high S/N values through the night so unless he was using an SDR that allowed the selection of multiple narrow filters for each stations, he must have legitimately and naturally decoded stations at these levels. Not that it really matters. If one’s ability to receive a station is enhanced with technology, thats great. +20 dB S/N is easy phone levels and that might be handy in the future. Congrats David on your excellent hearing. The path to the North from here has always been very good and I think good QSO’s will be had in the future. My WSPR transmission reports can be viewed here and my WSPR reception reports can be viewed here. Morning CW was very quiet and no additional QSO were completed.
103 MF WSPR stations were observed on the WSPRnet activity page at 0250z. KF3F and N1HOQ were new or newer receiving stations for this session. N1HOQ was reporting the “old” WSPR frequency of 503.9 kHz, however, suggesting that he was using software version 2.11. If he is using CAT to control his rig he will be listening on the wrong frequency and given that he had no reports, I suspect that will be the case. I will send an email later today. Welcome aboard!
Regional and continental WSPR breakdowns follow:
Eden, ZF1EJ, reported WD2XSH/15, WG2XIQ, WG2XXM, WH2XCR, WH2XGP, WH2XXP, and WH2XZO during this session. Report details for this session can be viewed here.
Laurence, KL7L / WE2XPQ, received late reports, just prior to dawn in the previous session. Those reports have been posted as an addendum in yesterday’s report. During this session, Laurence’s numbers are down a bit but he is currently experiencing active auroral conditions so this should not be surprising. He managed to share two-way reports with VK4YB and WH2XCR and was received by VK2XGJ, JA1NQI-2, JE1JDL, JH1INM, JH3XCU, and KH6L. Laurence’s mainland coverage focused on the West coast of North America. His DX report details can be viewed here.
Merv, K9FD/KH6 / WH2XCR, had a nice session with a strong showing in North America, including two-way reports once again with WG2XKA in Vermont and WH2XZO in South Carolina. He shared two-way reports with JA1PKG and VK4YB and received reports from VK2XGJ, 7L1RLL4, JA1NQI-2, JE1JDL JH1INM, JH3XCU, and ZL2BCG. I feel confident that Merv is quite loud at KH6L. Merv’s DX report details can be viewed here.
Jim, W5EST, presents, “PART 2: INTERPRETING SAMPLES/3sec.: ECHO MODE IN WSJT-X”:
“As blogged Nov. 23, the chopped-up graph of WG2XIQ signal strength variations reminded me of what I would see by looking at a graph of periodic QSB variations piecewise through gaps in a picket fence. http://njdtechnologies.net/112316/
A puzzling singleton wiggle also showed up in each of several of the QSB sinusoid pieces as seen through the “picket fence.” Today’s post explains why I think the puzzling signal strength wiggles resulted from 2-hop XIQ signal combining with the 1-hop XIQ signal. The wiggles are worth caring about, even though they’re only a minor feature of the XIQ strength graphs. The wiggles can help us better understand how multi-hop paths work, paths far longer than this short 485 km single hop path I tested Nov. 17.
QSB is slow amplitude modulation AM imposed by nature on the WSPR signal. Instead of audio, the QSB modulating frequency of WG2XIQ at W5EST that evening of Nov. 17 was 6 millihertz, more or less (6 mHz =~0.006 Hz, ~180 second period). Accordingly, the sinusoidal QSB “AM” on XIQ single hop had an average signal strength and a modulation percentage m.
Double hop propagation acted like a mixer of QSB patterns independently imposed on respective hops. Distinct QSB amplitude modulations became multiplied together, producing sum and difference frequencies. (See 1st end note.*) If each hop of 2-hop prop introduces QSB at a base frequency ~6mHz, then the receiver will sense a QSB component ~12 mHz as well. That 12 mHz component, I suspect, explains why some of the XIQ signal strength curves had a wiggle in them.
The double hop signal interacts with the ionosphere in two main places of sky reflection that differ in position from each other and from the probable mid-path place of one hop reflection. All that interaction can alter the timing of the wiggle relative to a main XIQ QSB curve. The period of the QSB was about 3 minutes, so a WSPR two minute time slot would cover 2/3 of a cycle. Accordingly, this double hop explanation explains how the wiggle behavior observed in the signal intensity data plots can arise.
This way, a double hop explanation of wiggle explains how such a variety of wiggle positions arise on the various one-hop sinusoids. A sum frequency is approximately, and not exactly, twice that of the one-hop component, so its wiggle is positioned differently in the different graphs that show it.
Presumably, the ionosphere at the different points of reflection along the short path was contributing QSB in roughly the same general way at each of those points. Consequently, modeling in the 2nd endnote** assumes equal modulation percentages for both sky reflections in 2-hop mode and further assumes those percentages to equal the modulation percentage of the 1-hop sky reflection. The modeling results show that a moderate amount of double hop contribution would introduce just one signal intensity wiggle per three minute period, e.g.
https://www.wolframalpha.com/input/?i=plot+0.5*(1%2B0.7*sin(x))+%2B0.9*0.25(1%2B0.7*sin(x-4.8+*pi%2F6))(1%2B0.7*sin(x%2B5.5*pi%2F6)+) (timeslots B1, B5, C4). A plot formula is:
0.5[1+0.7sin(2πf t)]+ 0.9*0.25[1+0.7sin(2πft -144°)][1+0.7sin(2πft +165°)]
where f is about 6 mHz and t is time. The plot may take a few seconds to come up on the web.
Roughly one-third of the graphs of XIQ WSPR transmissions don’t show a wiggle. That’s because of random positioning of the wiggle in the 3-minute QSB curve relative to whatever’s the relative position of the 2-minute WSPR timeslot on the QSB curve. The single wiggle per cycle is hidden outside the timeslot an average of one third of the WSPR transmission instances and revealed in the timeslot the remaining two thirds of WSPR instances.
A possible concern re this double hop explanation of wiggle is that the modeled double hop signal amplitudes that yield the observed wiggles can approach the single hop signal amplitude. (See 3rd endnote.***) Considering that a ground reflection is involved in double hop propagation, that aspect seems a bit uncertain. Nevertheless, the elevation pattern of my attic vertical antenna and the terrain here could conceivably condition the relative contributions of the 1-hop and 2-hop components by a few dB to make them comparable.
On this 485km path (XIQ-w5est at 60° azimuth) the single hop elevation angle is~22° from arctan[100km/(485km/2)]. Double hop elevation angle40° is considerably higher up: arctan[100km/(485km/4). A woods of ~25m tall trees lies southwest about 75 meters away from the RX, with a few trees closer. Hilly indented terrain extends at least a kilometer SW of the RX.
I considered six other explanations for the wiggle, and found the double hop explanation the least unpersuasive. (Discussions of each explanation are available on request). Even so, this double hop interpretation must remain unsettled unless and until signal intensity curves can be obtained for many more paths and stations. Signal strength information on WG2XIQ was taken here during one evening on one night on one short 630m path. Can you consider taking a night or two to do some WSJT-X Echo mode signal intensity monitoring?
Please try WSPR Echo mode on a storm free night to receive any 630m WSPR or QRSS station that in your experience reaches at least middle to strong single digits SNR and that your RX filtering can isolate from other such WSPR signals. Transfer and save the table of information that WSPR Echo mode displays, and attach it to an email. I would be happy to do the spreadsheet analysis and blog the results for you. TU & GL!”
*Note 1: Suppose that single-hop prop, and each hop 1 and 2 of double hop, introduce extremely slow sinusoidal amplitude modulation (QSB) about 0.006 Hz having a characteristic angular frequency ω, respective loss L per reflection, modulation percentage m, and phase θ in its wavelike modulation behavior. The QSB modulations respective to each hop’s sky reflection would be essentially independent in phase from each other. That’s because whatever physical processes are involved at each reflection point would take a considerable amount of time to influence each other. The amount of time would equal the distance between sky reflection points divided by the speed of sound in the ionosphere. Antenna gain Grx21 signifies elevation pattern gain dB (or loss) of higher angle double hop relative to lower elevation angle single hop. Multihop should leave a characteristic QSB pattern:
S = A L1 Lgnd L2…(½)N(1+m1 sin(ω1t+θ1))( 1+m2 sin(ω2t+θ2))… summed over 1,2,…N hops.
For single hop: S1h = A0 L0(½)[1 + m sin(ωt)]
S2h = A L1 Lgnd L2 Grx21(1/4)[1 + m1 sin(ωt+Δ1ω t + θ1) + m2 sin(ωt+ Δ2ω t + θ2)
+ m1 m2 sin(ωt+Δ1ω t + θ1) sin(ωt+ Δ2ω t + θ2)]
Total signal strength: S = S1h + S2h .
(The Δω terms account for the slight frequency differences between the various QSBs. The factor (½)N) for each given N-hop mode enables on-par comparison of loss coefficients.)
When you do the algebra, three significant terms emerge. The first term is the average signal level around which all the other contributions gyrate. The second term operates at ~1x frequency and may be responsible not only for the 3 minute XIQ QSB cycles but also deeply slow, longer-term variations in peak fade-up levels due to a very low frequency envelope factor on it—“deeply slow AM of the QSB AM” you might call it. Think of some nearly equal frequency sine waves ~6mHz in phasor form slowly swinging round and round in larger and smaller circles on a one-hour time scale such as one sees by looking at the XIQ signal intensity graph of his WSPR transmissions as a whole.
A third term represents a ~2x sum frequency: 2ωt+(Δ1ω+Δ2ω). We can expect it’s ~12 mHz. I believe it’s this faster-varying term embedded in the double hop contribution that produces the small wiggles on XIQ signal intensity. The wiggles migrated in position on the 6mHz QSB waveforms because of (Δ1ω+Δ2ω).
**Note 2: WG2XIQ transmissions A1, A4, C3, C5, D1, D5 lacked a wiggle or at least don’t obviously have it. B3 is too weak and indistinct to characterize. Plots of various trial and error curve fits are listed next for the other 13 out of the 20 WG2XIQ transmissions that show signal intensity wiggles as received at W5EST. The formulas suggest each sky reflection acts like an amplitude modulator operating with 70% QSB modulation percentage. Particular phase angles found by trial-and-error yield QSB curves and wiggles like those observed on XIQ.
https://www.wolframalpha.com/input/?i=plot+0.5*(1%2B0.7*sin(x))+%2B0.9*0.25(1%2B0.7*sin(x-4.8+*pi%2F6))(1%2B0.7*sin(x%2B5.5*pi%2F6)+) B1, B5, C4; plot 0.5*(1+0.7*sin(x)) +0.9*0.25(1+0.7*sin(x-4.8 *pi/6))(1+0.7*sin(x+5.5*pi/6) ) https://www.wolframalpha.com/input/?i=plot+0.5*(1%2B0.7*sin(x))+%2B0.9*0.25(1%2B0.7*sin(x%2B4.8+*pi%2F6))(1%2B0.7*sin(x-5.5*pi%2F6)+) A2, A5, C1, C2, D3; plot 0.5*(1+0.7*sin(x)) +0.9*0.25(1+0.7*sin(x+4.8 *pi/6))(1+0.7*sin(x-5.5*pi/6) ) https://www.wolframalpha.com/input/?i=plot+0.5*(1%2B0.7*sin(x))+%2B0.95*0.25(1%2B0.7*sin(x-5.5*pi%2F6))(1%2B0.7*sin(x%2B6.5*pi%2F6)+) A3, B2, D4; plot 0.5*(1+0.7*sin(x)) +0.95*0.25(1+0.7*sin(x-5.5*pi/6))(1+0.7*sin(x+6.5*pi/6) ) https://www.wolframalpha.com/input/?i=plot+0.5*(1%2B0.7*sin(x))+%2B1*0.25(1%2B0.7*sin(x%2B2.5*pi%2F6))(1%2B0.70*sin(x-6*pi%2F6)+) B4, D2; plot 0.5*(1+0.7*sin(x)) +1*0.25(1+0.7*sin(x+2.5*pi/6))(1+0.70*sin(x-6*pi/6) ).
***Note 3: Normalized amplitude of the single hop mode is 0.5(1+m) =~0.85 in this m=0.7 model. Double hop amplitude ~0.6 is estimated by plotting just the double hop component:
https://www.wolframalpha.com/input/?i=plot+0.9*0.25(1%2B0.7*sin(x-4.8+*pi%2F6))(1%2B0.7*sin(x%2B5.5*pi%2F6)+) B1, B5, C4; plot 0.9*0.25(1+0.7*sin(x-4.8 *pi/6))(1+0.7*sin(x+5.5*pi/6) ). Calculate S2h/S1h (dB) = 20 log10(0.6/0.85) = -3dB. Even supposing that dB calculation handles the additional sky reflection of double hop, its ground reflection loss seems unaccounted unless I appeal to local terrain-affected antenna pattern gain Grx21. Nevertheless, the Echo mode graphs of WG2XIQ-w5est receptions included the wiggle behavior that I propose double hop to explain.
Additions, corrections, clarifications, etc? Send me a message on the Contact page or directly to KB5NJD gmail dot (com).