NJDTechnologies

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

Current Operating Frequency and Mode

OFF AIR

Quieter geomagnetic conditions but QRN remains typically high for this session; Reasonably good band activity for July; WH2XGP -> ZL, WH2XXP -> VK, ZL; W5EST presents ”630m Sunrise SNR Seasonality”

– Posted in: 630 Meter Daily Reports, 630 Meters

The details for July 3, 2016 can be viewed here.

IMPORTANT REMINDER: Neither 630-meters nor 2200-meters are open to amateurs in the US yet.  Please continue to be patient and let the FCC finish their processes.  Click here to view the proposed “considerate operators” frequency usage guide for 630-meters under Part-97 rules that was developed with the input of active band users.

Storms continue to dominate the North American landscape, no doubt increasing QRN levels for many stations.  Even so, the band was open and long haul propagation continues on trans-Pacific paths.  Transcontinental openings were also presents so domestic propagation appears to have been pretty good a well in areas that were free of storms.

12-hour North American lightning summary

 

Geomagnetic conditions were less active than the storm levels of the previous session but continue at elevated to unsettled levels.  The Bz is pointing to the South and solar wind velocities are averaging near 415 km/s.  DST values are riding the centerline once again, moderating from the previous session.

 

 

 

Phil, VE3CIQ, reported that he decoded five WSPR stations and he was decoded by six unique stations.

Neil, W0YSE/7 / WG2XSV, reported that  he decoded three WSPR stations and he was decoded by twelve unique stations including two-way reports shared with WH2XCR, which was Neil’s best DX for the session.  Neil added that he “Cant get over those tall rocky mountains lately.”  Part of that may be the “thinning of the herd” due to central and eastern US storms.

Roger, VE7VV, reported that he generated  this table of modes (for which he is soliciting additions or corrections) that led to he and Toby, VE7CNF, engaging in a few daytime digital mode comparisons.  Here are some details:

“VE7CNF, Toby, and I ran a few tests today at 3 pm, daylight, groundwave, 63 km path. Toby ran 30W throughout and was 100% copy/print in all modes. We both used MultiPSK.

We started with CW, 20 wpm, my 10W was given RST 519, I gave Toby 569.

ThrobX2: 10W -1 dB S/N 100% print; 1W -10 dB 90%; 0.5W -14 dB 50%

PSK63: 10W 100% print.

PSK10: 10W 0 dB S/N 100% print; 1W -10 dB 100%; 0.5W -13 dB “3/5” quality, “missing a few letters”.

The PSK63 was interesting, it runs faster than either of us could type and was reliable on groundwave. I have found it virtually unusable on 20 mtr DX paths b/c of doppler/multipath effects. This mode could be very useful for local emergency traffic use with its apparently reliable high speed, at least during the day.

The PSK10 was also interesting, it was fast enough for casual chatting, very narrow BW. With 0.5 W it was giving quite usable print although Toby said the tone was almost inaudible, so below CW strength.

We need to try these modes on night time skywave to see how they fare then.”

This morning Roger indicated that John, VE7BDQ, was also monitoring the transactions and “…sent us his print that shows that he had good copy of both us in all modes except PSK10 which is not supported in his FLDigi.”

Mike, WA3TTS, reported “Six stations decoded overnight on 630m, best dx XXP. One ZF1EJ decode.”

Trans-Pacific report details, excluding KL7 and KH6, can be viewed here.

Hideo, JH3XCU, submitted these tables showing peak S/N and number of reports for DX -> JA for the session.

Roger, VK4YB, reported “Very similar pattern to the previous night. Jim, ZL2BCG, joined the SSB group on 479.00 kHz. His signal peaked at 59 in Brisbane over the 2409 km path.”  Roger received reports from JA3TVF and he provided reports for WH2XXP.

Ward, K7PO / WH2XXP, received reports from 31 unique stations including VK2XGJ, VK4YB, ZL2AFP, and ZL2BCG.

WH2XXP 24-hour WSPR activity (courtesy NI7J)

 

Larry, W7IUV / WH2XGP, provided reports for four WSPR stations and he received reports from nineteen unique stations including ZL2AFP and ZL2BCG.  As W7IUV, Larry provided reports for four WSPR stations.

WH2XGP 24-hour WSPR activity (courtesy NI7J)

 

Regional and continental WSPR breakdowns follow:

North American 24-hour WSPR activity

 

European 24-hour WSPR activity

 

Asian 24-hour WSPR activity

 

Oceania 24-hour WSPR activity

 

Eden, ZF1EJ, provided reports for three WSPR stations and he received reports from four unique stations including WH2XCR.

ZF1EJ 24-hour WSPR activity

 

Laurence, KL7L / WE2XPQ, provided reports for three stations during this session.

WE2XPQ 24-hour WSPR activity

 

Merv, K9FD/KH6 / WH2XCR, provided reports for VK1DSH, VK5FQ, and ZF1EJ.  He shared two-way reports with VK4YB and he received reports from VK2XGJ, ZL2AFP, and ZL2BCG.  Merv’s DX report details can be viewed here.

WH2XCR 24-hour WSPR activity

 

Jim, W5EST, presents 630m Sunrise SNR Seasonality:

“About seven months ago, with winter solstice only three weeks away,WSPR2 SNR data responded well to the favorable signal strength and short AZ-CA path from WH2XXP to N6SKM.  For Nov. 30, 2016, the SNRs spanned the entire dB dynamic range of night/day absorption of the ionosphere.  http://njdtechnologies.net/120116/

Fast-forward now to WSPR2 SNR for June 18-28, 2017. Today’s Figure 1 compactly shows the nighttime 630m SNRs (clustered +0dB to +17dB) flanked by steep increases from daytime levels around sunset SS and steep increases from nighttime levels around sunrise SR. You can see that 630m propagation along this path maintained quite similar dynamics for each of the nine days shown.

Daytime decodes may not have occurred, or perhaps inactivity excluded them on most of the days. Two of the days however did show some midday decodes around -30dB SNR or even weaker.

Figure 2 focuses on a recent typical sunrise SR– June 24– depicted by a red graph line at bottom right for comparison with blue-line SNR behavior around sunrise between the same two stations seven months before.  I have approximately aligned the Arizona sunrises of the two graphs even though the June 24 sunrise comes almost 2 hours prior to that of last November 30.  So far, no surprise, so let’s proceed on.

Purple horizontal arrows show SR-SR interval between TX and RX station sunrises was cut approximately in half—from 45 minutes to 24 minutes–between late fall and beginning of summer.

Night to daySNR dB dynamic range between Nov. 30 and June 24 appears to have widened a few dB but not a lot.  Pre-SR dB levels on November 30 were mostly near +8 dB with one instance about +12dB.   Post-SR dB descended to about -25 dB plus or -5 dB.  Range: 33dB (+8 –(-25)).

By contrast, Pre-SR dB on June 24 was mostly clustered either side of +10 dB with one instance about +17dB.   Post-SR dB descended to about -27 dB plus or minus 3 dB.   Range: 37dB (+10 –(-27)).

SNR position of Arizona sunrise (AZ SR) on the downramp was somewhat more puzzling to me.   I’ve drawn a horizontal dashed blue line halfway down on the SNR down-ramp for November 30, and analogously a horizontal dashed red line halfway down on the SNR down-ramp for June 24.  Please take a good look at the SNR position of AZ SR on the two days.

For November 30, AZ SR has its SNR position far above the blue “halfway line.”June 24 instead shows the SNR at AZ SR well below the red halfway line. I checked all nine days on the database between June 18-28 and their SNRs at AZ SR were all below the red halfway line.

This seasonal depression of 630m SNR at AZ SR indicates early onset of D-region absorption around summer solstice.  Why this matters, I think, is because it leads to the $64 question “Does early onset of absorption at a path midpoint relative to SR interfere with 630m SR enhancements?”

I’m not ready to venture an opinion about this SR enhancement question.   Before attempting to probe the seasonality of 630m SR enhancements, can we make sense of the features in the Figure 2 graphs? Part 2 will continue to grapple with the Figure 2 features.  See what you think in the meantime.  TU & GL!”


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