So yeah, I believe the band was a little better last night than the “OK” I gave the previous night for stations at mid and lower latitudes. It was, at the very least, much quieter than the previous night which may have contributed to higher and possibly more consistent S/N reports. A review of my overnight WSPR data showed significantly more (40% better?) CW-level reports compared to the previous night but it was a quieter night which will impact reports. The band showed high levels of QSB on signals and seems to have favored North / South paths over East / West paths, consistent with periods of high auroral activity as noted by Doug, K4LY / WH2XZO, in previous sessions. A JT9 QSO with WI2XBQ in northern California started on a peak and finished with several repeats required as signal dropped into the noise, the period of the QSB being only a couple of minutes.
Geomagnetic conditions are beginning to calm down, with the Kp moving into a quiet to unsettled range in comparison with previous sessions that experienced prolonged periods at storm levels. The Bz and solar wind velocities have been variable, pointing to the South and averaging near 650 km/s, respectively. Solar wind velocities dipped below 600 km/s to the low 500 km/s range during the daytime portions of this session have since intensified with the southerly Bz. DST values remain consistently at negative levels but have stabilized for the moment.
VO1NA was active again on 477.7 kHz CW and received reports from PA0RDT. Roelof provided the following comments and screen capture that look much better than the previous night when QRN was dominant:
“Propagation is recovering rather slow as this event is lingering on. The Kyoto Dst is still about -40 and this is day number 4 that shows this figure. Your signal was slightly better, but due to ongoing static, my ears did not make it this time! 73, Roelof, pa0rdt”
Riccardo, IW4DXW was active on Hellschreiber and received a report from Nicholas, F4DTL:
To the surprise of many, Stefan, DK7FC, reported that he was operating MF at QRP levels during the overnight session. His operating conditions and comments follow:
“Today i’m running some QRP on MF, just for fun. Raspberry Pi -> ICL7667CPA @ 13.8VDC -> pi-filter -> antenna matched to 50 Ohm. I measured 3.4 V rms on a 50 Ohm dummy load, i.e. abt 23 dBm output. What could the ODX become this night, with such inefficient amateur antennas?!! :-)”
In North America there was an impromptu JT9 session late in the evening. Joe, NU6O / WI2XBQ, was calling CQ near 474.2 kHz + 1200 Hz and requested a QSO. He received a number of CW-level reports from stations in the Pacific Northwest and we managed a QSO in the QSB as previously reported:
Neil, W0YSE/7 / WG2XSV, and Andy, KU4XR, were both watching the JT9 action from the sidelines and provided the following screen captures of the on-air activity:
Andy also provided a description to ongoing antenna comparisons at his station that was reported on the 600-meter research group. A transcript of that post can be viewed here.
Neil also added this morning that he decoded signals from ten WSPR stations and was decoded by eighteen unique stations, all of which were North and South, in addition to Hawaii. Neil adds that he decoded WG2XXM and my signal but was not decoded by either.
Phil, VK3ELV, received three reports from JH3XCU in the previous session and those details can be found here.
Roger, VK4YB, reports very heavy QRN from local storms but was still decoding WH2XXP and WH2XND in the desert Southwest. The path to the Pacific Northwest was poor, however, while the path to Japan was strong. Roger’s session details can be found here and his summary is shown below:
“Rx 8*wh2xnd (-21) 17*wh2xxp (-16) 17*wh2xcr (-17)
Tx 2*wh2xgp (-26) 2*ve7bdq (-25) 6*ve7sl (-22) 34*wh2xcr (-3) 7*je1jdl (-28) 2*ja1pkg (-24) 40*jh1inm (-14) 7*7l1rll4 (-29) 30*ja3tvf (-20)”
Roger also posted an announcement on the VK 600-meter yahoo group about the upcoming VI4SEA special event which I have linked from the billboard located on the front page of this website to the details which can be read here.
Larry, W7IUV / WH2XGP, reports good North / South paths in spite of continued high absorption. The East / West path was poor. Larry was decoded fourteen WSPR stations, including VK4YB, but reports that continued rainy conditions in Washington state result in intermittent transmissions due to his SWR protection tripping. VK4YB’s report is detailed in his session summary.
Ron, NI7J / WH2XND, received reports from 51 unique stations including VK4YB and VK5ABN. Ron’s trans-Pacific report details can be viewed here.
Ward, K7PO / WH2XXP, received reports from 55 uniques stations including VK4YB, VK5ABN, VK2XGJ, and VK3ELV. Ward’s trans-Pacific report details can be seen here.
Ken, K5DNL / WG2XXM, reported that he was decoded by 46 unique stations with 96 decodes from WH2XCR in 12 hours with best signal report of -4 dB S/N.
Doug, K4LY / WH2XZO, reported that “With continued disturbed conditions, only 7 decoded and decoded by 27. The N-S prop was good on 160M as well as 630.” Doug continues his work with the PY2GN remote receiver and reports that the dipoles currently being used for 630-meter receive that are designed for 80 and 160-meters don’t seem to be doing as well as they are in the broadcast band and 160-meters. Doug has inquired to Bill about whether the KiwiSDR has a preamp that can be activated to make up some ground. Doug continues to experiment with the remote SDR on HF during the day where signals are plentiful. Bill reported a few minutes ago that he has purchased a mini-whip, which may be a significant improvement. Stay tuned for details!
Dave, N4DB, reported seven WSPR stations with WH2XXP as his best DX at a distance of 3109 km.
Joe, NU6O / WI2XBQ, reported at 0413z that “+5@xcr, its just now SS. Could be an interesting night of TP. Only single hop <2500km East prop so far .” After 10z Joe reported, “Signals from 4QR 612khz down 10-20db from normal levels. N-S paths all in single digits, W-E paths depressed…The T index map shows normal HF conditions from W coast to VK http_link…I have been watching this map and it seems its inverted for MF conditions…Joe provided a very succinct description of MF propagation, which goes like this: “The E layer is in control of mf prop. One theiry is the E layer muf drops low enough for MF waves to reach the F layer for MF dx. Also the magnetic field has a huge impact due to the electron gyro frequency being at 1.2 mhz. in between 630 and 160. As we are finding out disturbed magneticc conditions can light things up or depress conditions. Paths that are perpendicular to the magnetic field are especially impacted (E-W). Tonight signals N-S were very strong, E-W depressed.”
Rick, W7RNB / WI2XJQ, has completed modifications to his station to improve his frequency stability, which will be reported next week in a write up posted on the 630-meter instructional page. Rick reports that the band has performed consistently over the previous several sessions with activity focused primarily on a North / South path plus KH6, Texas and Oklahoma. Rick decoded eleven WSPR stations and was decoded by 22 unique stations. A report detailing each unique station can be found here.
Ken, SWL-EN61, in Indiana reminded me that while I tend to focus on lightning as a QRN source, precipitation QRN may not manifest on the lightning map but it remains a very significant noise source. Ken also added that he has been observing profound differences in reception reports with Joe, WA9CGZ, who lives just 30-miles away in spite of relatively similar antennas. The most notable differences seem to be on western paths where one will hear those stations while the other will not. Then the process repeats. Spotlight is a likely candidate, at least from my perspective, but there may be a more elegant explanation. The idea of wave tilt differing over a short distance is not that far fetched. Ken ends noting that he has been experiencing the “northern penalty” that results from his latitude when absorption is as high as the most recent storm has created. I’ve been wondering recently whether there is a point of diminishing returns when moving towards the Equator with respect to good propagation versus noise. With the nightly storms in Mexico and central America, I may be in the sweet spot here in Texas. WH2XCR is located at a similar latitude as I am and experiences great propagation almost nightly but I suspect he is getting a little help from the salt water and his far western location.
I began the session on CW once again just prior to local sunset, transitioning to WSPR at 0130z. I received the following nice report from Ron, WA4JNX, in Alabama, who heard me calling CQ:
“Just heard a part 5 station near 473 khz calling CQ on cw…have heard this for several nights but could not copy it on the newly-built Jackson Harbor Press 14 buck vlf converter,50 foot wire and Sony 7600G rx…used the rx tonight with a modified AN-100 b/c loop (220pf cap across the variable takes it down to 380 khz). Which again shows ,if you want to get serious,use a loop 😊.73…ron,near BHM,AL with tons of noise.”
I really enjoy these types of reports because it means that stations are actually listening and being active participants as radio operators. Thanks for the report Ron! I hope there are many more. Ron also reported that the Jackson Harbor Press converter may not be long for this world and a final run may be in the works by Chuck. It has to do with parts availability. Get’em while their hot… and available!
This morning’s CW session started at 1010z and yielded a nice 30-minute sked where I did most of the “talking” until 1100z and a very quiet, relaxing noise floor until I stopped my CQing around 1220z.
Overnight WSPR reports were very good on the North / South path with moderately good reports on the extreme East / West paths here in Texas. The band was serviceable for CW for extended periods overnight if one took the time to figure out how the QSB was working. My WSPR transmission reports can be found here and my WSPR reception reports can be found here.
Activity was once again high during the session. 102 MF WSPR stations were observed on the WSPRnet activity page at 0130z but a review of the map and data suggests that there were many more by late evening.
Regional and continental WSPR breakdowns follow:
There were no reports from Africa during this session.
Eden, ZF1EJ, reported a number of stations in the southern US. While absorption continues to be high, poor weather conditions may be impacting stations in New England and the Pacific Northwest:
Laurence, KL7L / WE2XPQ, reports AC power problems as a result of weather so he was QRT for this session.
Merv, K9FD/KH6 / WH2XCR, had an interesting night. As with others, the North / South paths were most pronounced, giving numerous very strong reports in Australia with a relatively poor path to JA. Merv received stations well in North American including reporting me at a best -8 dB S/N but his signal struggled to get out of the low -20’s here in Texas on a quiet night. So it seems that East / West paths are very fickle but still capable of producing results if there is enough receiving headroom available. Merv and I could have completed another JT9 QSO last night I believe. Merv was hearing very well on the North / South path, reporting VK3ELV, VK3HP, and VK4YB. Merv’s VK and JA reports can be found here.
Jim, W5EST, presents, “PART 3: 630M WSPR RANDOM WALKS, WH2XZO TRANSMISSIONS”:
“Today I show evidence of random walk 630m SNR behavior generally occurring at midpoints of single-hops over eastern and central USA on 630m quiet nights in the last half of October.
Recall from yesterday’s blog that the telltale signature of random walk SNR behavior is zero-average, constant-variance randomness in time-differenced SNRs. Today’s first illustration shows exactly that in six more cases.
The upper row of time-differenced SNRs shows three different nights from WD2XSH/17 decodes of WH2XZO at 1260 km, with XZO heading NE at 48°. All show approximately the same amount of variability typical of 630m.
The lower row of time-differenced 630m SNRs shows XZO time-differenced SNRs for NE, W, and NW headings and various single-hop distances from 1086 km to 1407 km. Again, all show approximately the same amount of variability and the zero-average.
Let’s segue to the second illustration which shows the 630m SNRs themselves arrayed to correspond to positions on the first illustration. Time flows from right to left from sundown through the night. To my eyes, three of these plots hump up in the night and then decline, and three of the plots show strong peaks and deep valleys without much sign of overnight trend. See what you think. These SNR plots are random walks.
This kind of quiet-night behavior on 630m amounts to SNR statistical drift. Assuming 630m band noise was relatively steady in each receiver, it was signal strength that drifted. When I say statistical drift, I mean random variation due to physical processes that are too difficult for us as amateurs and experimenters to either monitor ourselves or obtain from some geophysical data source. So we just gather up the resulting changes in SNR over time and statistically treat them as the random variations that the first illustration shows.
When SNR statistically drifts as a random walk, SNR can–by the random walk dynamic alone–reach substantial levels of strength. The SNR can also dip down to deep SNR troughs at different times of night.
Although XZO statistically drifted as a random walk on different paths and nights, each sequence of SNRs presumably was the result of physical processes. I wondered why SNR, which is a logarithm of power ratio S/N, executed a random walk and not the power ratio S/N itself. Then I was reminded that signal power can’t be less than no power at all. So, the variability of signal power S must get less as signal power nears zero. But its logarithm that leads to SNR can still have the same variability whether the signal power is large or small. Consider the physical aspects that condition receivable signal power as it traverses the distance – like ionization, electron concentration contour tilt, and fraction of signal power polarized vertically. All these physical aspects have a natural zero–their “nothing.”
Storm noise and sunrise and sunset do remain highly influential deterministic contributions to 630m SNR, of course.
I think of a random walk SNR like water level in a tank that has a signal strength “QSB spigot” randomly turning on and off a water source to it and also has a QSB faucet randomly draining water out. The SNR water level will change slowly either in a large-capacity water tank or one that has only small rates of water-flow in and out. Perhaps in some other blog post a formula might estimate “630m quiet night SNR capacitance” ! TU & GL.”
Additions, corrections, clarifications, etc? Send me a message on the Contact page or directly to KB5NJD gmail dot (com).