QRSS Meteor Scatter on 30 and 17m During the November Leonids Meteor Shower

Introduction

During previous meteor showers W4HBK, WD4AH and WD4ELG have observed meteor pings on 17 and 20m using QRSS techniques at sub-Watt power levels.  As discussed in a previous blogs we needed to adjust our approach for our next shower and see if we could do better on 17m and  go one band lower to 30m.

During the November 2018 Leonids Meteor Shower we used the 17 and 30m QRSS bands to look for meteor pings .  We have previously had moderately good success on 17 and 20m and our goal this test was to improve our success rate using "lessons learned" and to go one band lower and see if pings were observable on 30m.

Experimental setup

W4HBK:  tx on 30m using a U3S running 700 mW to an inverted V antenna and rx on 17m
WD4AH:  tx on 17m using a U3S running 500 mW to a random wire antenna and rx on 30m
WD4ELG rx on 17 and 30m

HBK is 276 miles/444 km from AH and 580 miles/935 km from ELG
ELG is 466 miles/750 km from AH

Based on previous tests we found that a near continuous signal with minimum frequency shift made it easiest to identify pings and can be adjusted for as little dead air time as possible.  Hence we used fskcw with a 1 Hz shift with the dot-second time adjusted to transmit for 9 minutes and allow 1 minute to cool the finals at the end of a 10 minute frame.  The duration of the test was from just after midnight (0700z) to just past Sunrise (1300z).

I also used a program called SeqDownload to record the grabber screens at AH and ELG directly to my computer in real time so that it would not be necessary to download from their archives after the test, via the Internet.  This greatly simplifies and reduces the time to process the data and avoids confusion.

Results

     17m

We were able to record many pings on 17m between W4HBK and WD4AH.  Figure 1a is a typical ping and Figure 1b is a stitch of all grabs to give an idea of the total number of observed pings.

Figure 1a  Typical  ping on 17m from WD4AH at W4HBK

Figure 1b  Stitch of all 17m grabbs of WD4AH by W4HBK

WD4AH also had 5 pings on the WD4ELG grabber, Figures 2a and 2b show two examples.

Figure 2a  Meteor Ping of WD4AH received by WD4ELG

Figure 2b  Second example WD4AH at WD4ELG

30m

Only a few weak pings were recorded of W4HBK at WD4ELG, Figures 3a and 3b.

Figure 3a  W4HBK received by WD4ELG on 30m

Figure 3b   W4HBK received by WD4ELG ON 30m

WD4AH recorded a number of pings from W4HBK.  Figures 4a and 4b are representative.  Figure 5 is a stitch of all grabs to give an idea of the total number of pings.  Note at right the band begins to open and HBK's signal becomes a combination of meteor scatter and weak propagation.

Figure 4a  W4HBK received by WD4AH on 30m

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Figure 4b  W4HBK received by WD4AH on 30m

   

Figure 5  Stitch of grabs by WD4AH of W4HBK on 30m

     Special Event

At 0916z all four grabbers recorded pings.  In addition, judging by the long duration of W4HBK at WD4ELG (Figure 3b) this may have been a fireball event.

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Conclusions

Meteor scatter is very easy on 17m QRSS over a distance of 276 miles while difficult over  a distances of 466 and 580 miles.

On 30m it is fairly easy on the shorter path and difficult on the longer one.  Additional problems on the lower bands are QRM from other signals and modes of propagation.  Examples of the latter are tropo ducting and unexpected Sporatic E.

Great care must be taken to rule out false pings from these problems.  I do this by looking for letters of the call or elements of the letters as well as the characteristic signature of meteor pings. A single dit or dah at the right time can verify the sending station.