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

Current Operating Frequency and Mode


G1 storm levels didn’t provide much of a bump to propagation at event onset; Trans-Pacific reports were the session highlight and they were not that great; W5EST presents: ”Viewpoint: 630M Sunrise Simulation and Relation to 8/21 Solar Eclipse”

– Posted in: 630 Meter Daily Reports, 630 Meters

The details for August 17, 2016 can be viewed here.

IMPORTANT REMINDER: Neither 630-meters nor 2200-meters are open to amateurs in the US yet. That includes stations using fake or pirated call signs. Please continue to be patient and let the FCC finish their processes. UPDATED: 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 were found from the Midwest to Mexico with the main event seemingly setting up shop over my station in North Texas.  It was the right decision to shut down at bedtime as I was able to just roll over once the flashing and rumbling started this morning.  The Caribbean, parts of central Canada, and a few areas in the West also experienced a few evening storms.  The East was generally reported to be quiet to moderately quiet although a strong system was active in the Atlantic.

11-hour North American lightning summary


Geomagnetic conditions reached G1 storm levels after quiet conditions for several sessions.  The Bz was pointing strongly to the North before sunrise but has since turned strongly to the South and solar wind have reached near 530 km/s. DST values experienced only a very slight peak before decreasing significantly, which is abnormal.  It seems that no enhancement was observed during this event.




Neil, W0YSE/7 / WG2XSV, reported that he was decoded by seventeen unique stations including WE2XPQ in Alaska and WH2XCR in Hawaii but Neil notes that he had no reports East of Alberta. He provided reports for six WSPR stations including VE7BDQ, VE7CA, WH2XCR, WH2XGP, WH2XXP, and WI2XJQ.  Neil added that “N7IW about 35 miles south of me has been decoding me recently.  Dont know if he is new or just returning.”

Doug, K4LY / WH2XZO, reports, “Last night continued fairly noisy with 5 stations decoded and 22 decoding WH2XZO. The SC jungle has grown up around my two unusable directional receive antennas.   Machete time!”

Rick, W7RNB / WI2XJQ, provided reports for eight WSPR stations and he received reports from thirteen unique stations.


08:20 WH2XCR 0.475618 -28 0 BL11je 1 WI2XJQ CN87ts 4287 38
07:30 WE2XPQ 0.475796 -28 0 BP51ip 10 WI2XJQ CN87ts 2287 120
05:40 VE7BDQ 0.475736 -2 0 CN89la 0.5 WI2XJQ CN87ts 147 160
05:08 26XSH 0.475703 -25 0 CN98pi 0.1 WI2XJQ CN87ts 140 243
03:12 WH2XXP 0.475663 -23 0 DM33 50 WI2XJQ CN87ts 1771 337
03:02 VE7CA 0.475682 -7 0 CN89ki 2 WI2XJQ CN87ts 185 162
02:20 WH2XGP 0.475689 -11 0 DN07dg 5 WI2XJQ CN87ts 208 286
01:58 WG2XSV 0.475761 -25 0 CN85rq 2 WI2XJQ CN87ts 232 3


07:16 WI2XJQ 0.475611 -22 0 CN87ts 5 WE2XPQ BP51ip 2287 322
06:16 WI2XJQ 0.475611 -21 0 CN87ts 5 WB6HYD CM87xi 1159 179
06:06 WI2XJQ 0.475612 -23 0 CN87ts 5 WH2XCR BL11je 4287 239
06:06 WI2XJQ 0.475612 -25 0 CN87ts 5 W7WKR CN97uj 162 104
05:58 WI2XJQ 0.475612 -26 0 CN87ts 5 VE7BPB CN89lg 174 344
05:42 WI2XJQ 0.475612 +10 0 CN87ts 5 W7IUV DN07dg 208 105
05:42 WI2XJQ 0.475611 +8 0 CN87ts 5 WH2XGP DN07dg 208 105
05:36 WI2XJQ 0.475609 -4 0 CN87ts 5 VE7BDQ CN89la 147 341
04:52 WI2XJQ 0.475613 -28 0 CN87ts 5 KO6KL CM97kr 1121 174
04:52 WI2XJQ 0.475611 -8 0 CN87ts 5 VE6JY DO33or 944 42
04:52 WI2XJQ 0.475611 -14 0 CN87ts 5 WW6D CM88pl 1034 182
04:52 WI2XJQ 0.475611 -15 0 CN87ts 5 WG2XSV CN85rq 232 183
04:52 WI2XJQ 0.475611 -3 0 CN87ts 5 VE6XH DO24tc 899 35


Al, K2BLA / WI2XBV, provided reports for four WSPR stations through moderate noise during his brief listening session this morning.  Al notes that his local weather is deteriorating so his antennas and station have been secured.

Mike, WA3TTS, reported that he decoded six WSPR stations overnight, including  one report for “…XGP at 0536 -22, also XXP, XZO, XUF, XXC, XJM.”

Dave, N4DB, reported that he decoded six WSPR stations including WH2XXP and ZF1EJ as his best DX.  Dave added that noise was “fairly low” and no storms were observed in his area of Virginia.

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

Hideo, JH3XCU, submitted this link detailing DX -> JA decode totals and DX -> JA S/N peaks for the session, as reported on the Japanese language 472 kHz website.

Roger, VK4YB, reported “High QRN again. Good paths later to PNW and Alaska. Very high winds are forecast for the weekend so antenna work may not be possible.”  He received reports from JA1NQI/2, VE6JY, VE6XH, W7IUV, WH2XGP and WE2XPQ. He shared two-way reports with WH2XCR.

Ward, K7PO / WH2XXP, received reports from 41 unique stations including VK4YB and ZL1BPU.

Larry, W7IUV / WH2XGP, reports that he was off air over night due to a wild fire about a mile from his property.  He seems OK and was able to operate a bit this morning and before he lost power last night.  He provided reports for nine WSPR stations including VK4YB and he received reports from eighteen unique stations. As W7IUV, Larry provided reports for eight WSPR stations including VK4YB.


Regional and continental WSPR breakdowns follow:

North American 24-hour WSPR activity


European 24-hour WSPR activity


Japanese 24-hour WSPR activity


Oceania 24-hour WSPR activity


Eden, ZF1EJ, provided reports for four WSPR stations. He received reports from ten unique stations with the bulk of all of his reports located due North of his station.

ZF1EJ 24-hour WSPR activity


Warwick, E51WL, provided late reports for VK4YB during the previous session. Those report details can be viewed here.

Laurence, KL7L / WE2XPQ, provided reports for six WSPR stations including VK4YB and he received reports from five unique stations. He shared two-way reports with VE7BDQ, VE7CA, WH2XCR and WI2XJQ.  DX report details can be viewed here.

WE2XPQ 24-hour WSPR activity


Merv, K9FD/KH6 / WH2XCR, provided reports for nine WSPR stations. He shared two-way reports with VK4YB and WE2XPQ.  Merv received reports from eleven unique stations including VK2XGJ and ZL2BPU.  This was a very different session from the previous and storms in the Tasman sea certainly did not help listening in Oceania.  DX report details can be viewed here.

UPDATE:  Merv indicates that he reported Roger one hour after sunrise in KH6:

Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
16:50  VK4YB  0.475637  -27  0  QG62ku  0.5  WH2XCR  BL11je  7597  50

WH2XCR 24-hour WSPR activity



“Today’s illustrations compare my latest spreadsheet simulation (Endnote*) of 630m SNR (red) at sunrise vs. instances of WH2XXP and WH2XND SNRs at N6SKM around sunrise Nov. 5, 6, 7 and 30, 2016. Information on surface weather for all four days suggests no significant weather interference on the path.

The 630m sunrise simulation calculates distances sun rays take through the D -region where solar ionizing radiation goes to finally reach the 630m RF path at its ascending and descending crossings of the D-region. Longer or shorter such distances through the D layer make for higher or lower SNR. That’s because of less or greater RF absorption induced by whatever solar ionizing radiation finally reaches a D-region crossing by your 630m RF. See illustration at: http://njdtechnologies.net/073117/

For those particular stations on those particular days, you can see that the simulation quite poorly predicts the sunrise SNR from decode to decode.  For Nov. 5-7, the simulation mostly predicts lower SNRs than were actually reported. The Nov. 30 graph for WH2XXP-n6skm shows the least disparity between simulated SNR and actual SNR. Even there much unaccounted variability above and below the simulation curve remains.

You are welcome to dismiss the whole exercise as meaningless, considering some 15-20 dB disparities between some predicted and actual SNRs on Nov. 5-7. Nevertheless, I’ll state my viewpoint, for what it’s worth.

I think the Nov. 30 SNR graph indicates that a physically-based conceptual picture of solar ionizing radiation passing through the D-region to reach the RF path does represent a skeleton of explanation within some bigger, yet-to-the-determined account of these SNRs. On that Nov. 30 day out of the four days graphed, the actual SNR did decline as rapidly as, and consistent with, the general decline in the simulated SNR.  Also, no D-region ionizing time constant is included, which could improve the curve fit to the actual data.

As I understand it, the D region is considerably thinner and little-ionized at night, but much thicker and much more ionized in the daytime.  Around sunrise, such D-region thickness variation suggests that the D-region varies in thickness and ionization due to the varying distances through the D region through which the sunrise regime solar ionizing radiation must pass. As I see it, that represents considerable disturbance to the D region that could physically stir its material up on its way into the morning daytime. Disturbance may leave spaces of low RF absorption in the D-region for a while after sunrise.

Now for the connection to this Monday’s solar eclipse, August 21. The solar eclipse will happen well after sunrise and on into this Monday morning and on into the afternoon. Times depend on your location in southern Canada and the lower-48 USA. After the eclipse crosses a given 630m RF path connecting to your area, solar ionizing radiation will rapidly increase in strength in the wake of the eclipse oval of totality. That could disturb or stir the D-region. We should keep transmitting and receiving for some time afterwards in case any “sunrise bumps” in SNR recur after the main eclipse peak SNR pattern.

With plenty of station activity and high WSPR transmit percentages on Monday we can hope for deeper insight into the ionospheric environment in which 630m operations play. TU & GL!

*Endnote: Simulation spreadsheet is available on request to me at  mrsocion@aol.com . The RF path itself was assumed to be aligned with Sun’s rays at sunrise for simulation purposes.  Consider distances w1 and w2 across which solar ionizing radiation must pass to reach D-region crossing points 1 and 2 for a 630m RF path.
Let w1 = w11 + w12  and w2 = w21 + w22.
Second subscript 1 or 2 represents distance on the post-SR and pre-SR side of the terminator, respectively.
Let angle a be the angle between the terminator and a given D-region crossing of the RF, with Earth’s center as angle vertex. Angle values pre-SR west of terminator are negative.
Define A, B, C as follows. A: distance along Sun’s rays from bottom of D-region to terminator. B: distance from middle of D-region to terminator.  C: distance from top of D-region to terminator.   Use the TABLE and formulas farther below to calculate w11 and w12.
w21 and w22 are calculated same way except with angle a decreased by whatever angle between the two D-crossings applies to the RF path. Simulation produces a curve for w1 and another nearly identical curve for w2, just delayed by an angle based on path distance D=925km for XXP-n6skm and path fraction k = 0.278 to first D-region crossing.  Delay angle ad offsets all radian values line-by-line in the spreadsheet for the calculation of w21 and w22 relative to calculation of w11 and w12 by this amount:
        d = (2k-1) D/RE
Earth radius RE = 6371 km.  Delay angle ad is calculated by the spreadsheet for the special case of RF path aligned with sunrise. Other path orientations will involve other delay angle values and probably more refined formulas.
Simulation parameters:  hoz: Ozone layer top height 30km. hD : D-region middle height 75 kmΔhD/2: D-region half-thickness 15 km except hypothetically tapered from 15km at -0.23rad down to 8 km at -0.09 radian to terminator and then tapered up to 15km again at +0.14 radian.

        A = (RE+hD) cos(a)  SQRT{ -1 + [ 1- ΔhD/(2(RE+hD)) ]2 /cos2(a) }
        B = (RE+hD) cos(a)  SQRT{ -1 + [ 1/cos2(a) ] }
        C = (RE+hD) cos(a)  SQRT{ -1 + [ 1+ ΔhD/(2(RE+hD)) ]2 /cos2(a) }
Calculations begin at an angle a = a0 when sun rays graze top of ozone layer and reach D-region at eastward D-region crossing of RF path. Before that, assume fictitious nighttime thickness of D-region to sun ionizing radiation = 500km.
        a0 = – arccos {(1+ hoz/RE)/(1+ (hD+ΔhD/2)/RE)}, e.g. -0.1364 rad for assumed altitudes.
In terms of the distances w1 and w2 across which solar ionizing radiation must pass to reach D-region crossing points 1 and 2 for a 630m RF path, define a constant
         z0 = [w1(night)+w2(night)] / [w1(noon)+w2(noon)],
Set up constants as follows: SNRdB(night) = +10dB, dBnoon = -35dB (daytime absorption of D-region). Set up z0 based on  w1(night) = w2(night) = 1000 km, and
w1(noon) = w2(noon) = 15 km. (half-thickness assumed for noontime D-region).
Further define a variable z(a) as a function of angle a:
         z(a) = [w1(a)+w2(a)]/ [w1(noon)+w2(noon)],
Finally, perform a linear fit involving distances w1(t) and w2(t) to get simulated SNR:
        SNRdB(a) = SNRdB(night)  –  dBnoon  (z0 – z(a)) / (z0-1).
Graph the resulting points and mouse-expand to fit over actual SNR graph. To do this,
establish east D-region crossing angle values a1 and a2 for moments when 630m stations at the RF path ends have their station sunrise by crossing the terminator. Graphically overlay the curve SNRdB(a) onto the graph of actual SNRs so that the Simulated SNRs corresponding to those two angles a1 and a2 match to the sunrise times of the actual SNR graph.
        a1 =      – k D/RE , e.g. = -0.0404 rad. , sim. SNR -8.14 dB (after 2nd downstep)
        a2 = (1-k) D/RE , e.g. = +0.1051 rad. , sim. SNR  -19.7 dB




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