This morning after a very nice 0800z CW rag chew with Eric, WG2XJM / NO3M, who was using the vintage Hartley oscillator driving the SB1000 on 474.5 kHz, I received a curious email and screen shot from David, VK2DDI, regarding my WSPR signal:
“I'm seeing what appears to be a rather broad and very weak signal on about .622 with 50% duty cycle. Could be anything, but with conditions a little odd we may be in for a good ride. Lets hope so. Screenshot is below FYI.”
The smudges at 622Hz are quite pronounced and occurring at the same time, duty cycle and frequency that I am transmitting. While I am not a strict adherent to Occam’s Razor, if it looks like a duck…
A post-mortem indicates no decode occurred and a similar trace was obvious for Rudy, WD2XSH/20, near his transmit frequency closer to his sunrise on the west coast. As with me, Rudy was not decoded.
The GMF is currently very unsettled and active so no doubt that is a strong influence for this type of ionospheric behaviour. I like to visualize the profoundly disturbed geomagnetic field as a magnet placed near an old cathode ray screen. The resulting analogous distortion seems to force some of my signal further south, allowing for this path to develop while allowing a portion of my signal to continue on to its northern destination, being further attenuated along its path. In fact, the data reflects this attenuation quite well. Larry, WH2XGP / W7IUV indicated that just prior to and during the August 25, 2014 event, my signal was very weak. Immediately after the report by David in VK, Larry indicated that the signal levels returned to normal levels. This event was active. In order to maximize my chances for a repeat event, the transmit cycle has been increased to 50%, literally 2 minutes on, 2 minutes off.
Equally intriguing, while in QSO with Eric, I noted that the loop was hearing him at true-599 levels while there was no hint of signal at all on the vertical. The exact opposite was true for Ken, WG2XXM / K5DNL, located in Shawnee, OK about 200 miles north. Ken’s signal was very strong with the transmit vertical and very weak on the loop. I will wait to speculate until further analysis can be considered.