CAN EME QSO's STILL BE MADE UNDER EXTREMELY HIGH DEGRADE CONDITIONS?
(July 2nd, 2015)
Over the last 2 days, the "Degrade" Factor (Dgrd) was extremely high. As it is generally the case during periods of high degrade, there was virtually no activity on the EME sub-band, with very few stations on the logger. Why is that? Although rendering QSO's more challenging, is a high degrade index really such a show stopper in the field of EME communications? This has been puzzling me for a while now, so using the Moon Echo Project capability, I have been trying to conduct experiments which hopefully would help shedding light on this issue.
Following the experiment described in Section 27, which demonstrated with hard evidences (video) that it was possible to produce "Moon Echos" with very simple means despite an extremely high degrade factor, I decided to repeat the experiment to ensure that it could be replicated, as good science demands just that.
This time around, the degrade factor was at -11.5 dB. The video clip to the right shows a portion of the test in question. For this experiment, the same TX/RX scheme described in Section 27 was employed, which is:
TX: 2X14 RPOL/KW (roof)
RX: 1X13 RPOL LFA (backyard)
The RX polarity of the 1X13 RPOL antenna was set to 0 degree (H-POL). Only the TX polarity was changed. After a few seconds trying different TX polarities, Moon Echo traces starting showing up on the waterfall. Once again, it was possible to produce good quality and detectable "Moon Echos" in the -27dB to -30dB range using very simple TX/RX means despite the extreme Degrade Conditions (-11.5 dB). Although the signals produced were weak considering the poor conditions, the overall quality of the Echo Traces produced (often very visible) suggest that good EME QSO's could easily result from such signal intensities. In other words, the experiment, which has been successfully done twice now, clearly indicates that EME QSO's can still be made during periods of extremely High Degrade, even between relatively small/low ERP stations!
Why isn't there more EME activity during such periods of High Degrade? There seems to be a false thinking out there which suggests that it is completely useless to try to do any EME work during periods of very high degrade. Very clearly, the facts and evidences suggest something different...
***WARNING: For Best Resolution for the videos below, it is critical to select 720p HD resolution in the youtube "settings" at bottom right of the player. The 360p default setting won't yield good enough resolution to see the details. It will take several seconds before the High Resolution kicks in, so you will need to restart the video from the beginning when the High Resolution is active and select to view the video in "Full Screen Mode" for best experience...***