Meteor scatter observations 13.08.2019 - 14.08.2019

SDR technique offers great capabilities in such a type of DXing as meteor scatter (MS) observations on VHF bands (OIRT/CCIR FM, HAM, AIR etc.). In contrast to other propagation modes (Es, Tropo), SDR equipment gives absolutely overwhelming advantage over conventional receivers by reason of pretty short characteristic time of MS events: rarely up to several minutes (bursts), but mostly up to several seconds (pings).

It is obvious, that multi-frequency monitoring with a conventional receiver at such short openings is quite difficult. So, SDR is an invaluable aid for those who want to dedicate their free time to this interesting type of DXing.

MS DXing with SDR reminds me of  fishing: one is recording gigabytes of "empty" frequency spectrum many megahertzes wide and waiting for more or less rare bursts ("bites") of signals for hours. Then one can sort the "catch" out, identifying big "fish" and releasing little unidentifiable "hutchling". The process of "sorting" is more difficult than in a case of Es or Tropo, but RDS decoding (sometimes), station's playlists and podcasts on the Internet can help considerably.

Similar to fishing, MS observations can be successful in full measure only at special conditions: on the days of meteor shower activity, when cosmic debris entering Earth's atmosphere and burning there leaving a trails of ionized gases. These trails can reflect radio waves of wide range of frequencies including OIRT/CCIR FM frequencies.

One of the most intense meteor showers happens in the second half of summer. The name of this shower is Perseids because its radiant is located in Perseus constellation (really on the boundary of Perseus and Cassiopeia). It usually starts from about 17th of July, reaches maximum on 13th of August and ends on 24th of August:

As the heights of the meteor trails lie within 80 - 120 km range, maximum possible distance of signal propagation is usually 2200 - 2500 km, however it can even be longer in a case of combination of meteor scatter with tropospheric ducting.

Here are results for some identified (completely or tentatively) bursts on 13.08.2019. The bursts were observed at 11.48, 11.59, 13.02, 17.36 and 17.49 UTC, radio stations from Germany, Czech Republic, Poland and Austria were received:

11:48	87.60	MHz	D	hr3	Sackpfeife (Biedenkopf)	100	kW	1540	km	281	°
11:48	87.70	MHz	D	MDR Kultur	Chemnitz/Geyer	100	kW	1240	km	278	°
11:48	87.90	MHz	D	MDR Kultur	Inselsberg	60	kW	1410	km	280	°
11:48	88.30	MHz	POL	PR 1	Opole/Chrzelice	60	kW	900	km	276	°
11:48	88.50	MHz	CZE	ČRo Radiožurnál	Trutnov/Černá Hora	16	kW	1040	km	278	°
11:48	91.70	MHz	D	MDR Thüringen	Sonneberg/Bleßberg	100	kW	1370	km	278	°
11:48	91.80	MHz	D	MDR JUMP	Löbau/Schafberg	5	kW	1110	km	280	°
11:48	89.30	MHz	D	hr3	Großer Feldberg (Taunus)	100	kW	1560	km	278	°
11:48	89.50	MHz	D	hr3	Hoher Meißner	100	kW	1450	km	282	°
11:48	89.80	MHz	D	MDR JUMP	Chemnitz/Geyer	100	kW	1240	km	278	°
11:48	89.90	MHz	CZE	ČRo Dvojka	Liberec/Ještěd	15	kW	1090	km	278	°
11:48	90.20	MHz	D	MDR JUMP	Inselsberg	100	kW	1410	km	280	°
11:48	90.40	MHz	D	MDR JUMP	Leipzig Wiederau	100	kW	1280	km	281	°
11:48	90.70	MHz	D	Bayern 1	Ochsenkopf (tent.)	100	kW	1320	km	276	°
11:48	90.90	MHz	CZE	ČRo Radiožurnál	Ústí nad Labem/Buková Hora	100	kW	1150	km	278	°
11:48	91.00	MHz	D	hr1	Sackpfeife (Biedenkopf)	100	kW	1540	km	281	°

11:59	90.10	MHz	D	MDR JUMP (tent.)	Dresden-Wachwitz	100	kW	1170	km	280	°
11:59	90.20	MHz	D	MDR JUMP (tent.)	Inselsberg	100	kW	1410	km	281	°
11:59	90.90	MHz	CZE	ČRo Radiožurnál	Ústí nad Labem/Buková Hora	100	kW	1150	km	278	°
11:59	91.00	MHz	D	hr1	Sackpfeife (Biedenkopf)	100	kW	1540	km	281	°
11:59	91.50	MHz	POL	PR 3 (tent.)	Lubań/Nowa Karczma	60	kW	1080	km	281	°
11:59	91.70	MHz	D	MDR Thüringen (tent.)	Sonneberg/Bleßberg	100	kW	1370	km	278	°
11:59	91.70	MHz	POL	PR 3 (tent.)	Częstochowa/Wręczyca	60	kW	820	km	278	°
11:59	92.20	MHz	D	MDR Sachsen (Dresden)	Dresden-Wachwitz	100	kW	1170	km	280	°

13:02	88.80	MHz	CZE	ČRo Sever	Ústí nad Labem/Buková Hora	100	kW	1150	km	278	°
13:02	89.70	MHz	CZE	ČRo Radiožurnál	Pardubice/Krásné	100	kW	1050	km	272	°
13:02	89.80	MHz	D	MDR JUMP (tent.)	Chemnitz/Geyer	100	kW	1240	km	278	°
13:02	90.20	MHz	D	MDR JUMP (tent.)	Inselsberg	100	kW	1410	km	281	°
13:02	90.50	MHz	CZE	ČRo Hradec Králové	Trutnov/Černá Hora	20	kW	1040	km	278	°
13:02	90.90	MHz	CZE	ČRo Radiožurnál	Ústí nad Labem/Buková Hora	100	kW	1150	km	278	°
13:02	91.40	MHz	CZE	Radio Impuls	Plzeň/Krašov	100	kW	1230	km	275	°
13:02	91.70	MHz	POL	PR 3 (tent.)	Częstochowa/Wręczyca	60	kW	820	km	278	°
13:02	92.10	MHz	CZE	Radio Impuls	Trutnov/Černá Hora (tent.)	16	kW	1040	km	278	°
13:02	92.20	MHz	D	MDR Sachsen (Dresden) (tent.)	Dresden-Wachwitz	100	kW	1170	km	280	°
13:02	91.70	MHz	D	MDR Thüringen (tent.)	Sonneberg/Bleßberg	100	kW	1370	km	278	°

17:36	91.20	MHz	D	SWR 4 Baden-Württemberg	Waldburg	25	kW	1530	km	267	°
17:36	91.50	MHz	AUT	ORF Radio Niederösterreich	Sankt Pölten/Jauerling	100	kW	1120	km	264	°

17:49	87.90	MHz	D	MDR Kultur	Inselsberg	60	kW	1410	km	280	°
17:49	88.50	MHz	CZE	ČRo Radiožurnál	Trutnov/Černá Hora	16	kW	1040	km	278	°
17:49	88.80	MHz	CZE	ČRo Sever	Ústí nad Labem/Buková Hora	100	kW	1150	km	278	°
17:49	89.10	MHz	CZE	ČRo Radiožurnál	Plzeň/Krašov	100	kW	1230	km	275	°
17:49	89.30	MHz	D	hr3	Großer Feldberg (Taunus)	100	kW	1560	km	278	°
17:49	90.50	MHz	CZE	ČRo Hradec Králové	Trutnov/Černá Hora	20	kW	1040	km	278	°
17:49	90.60	MHz	D	hr1	Hardberg	50	kW	1550	km	275	°
17:49	90.70	MHz	D	Bayern 1	?	100	kW	????	km	???	°
17:49	90.90	MHz	CZE	ČRo Radiožurnál	Ústí nad Labem/Buková Hora	100	kW	1150	km	278	°
17:49	91.40	MHz	CZE	Radio Impuls	Plzeň/Krašov	100	kW	1230	km	275	°
17:49	87.70	MHz	D	MDR Kultur	Chemnitz/Geyer	100	kW	1240	km	278	°
17:49	91.00	MHz	D	hr1	Sackpfeife (Biedenkopf)	100	kW	1540	km	281	°
17:49	91.70	MHz	D	MDR Thüringen	Sonneberg/Bleßberg	100	kW	1370	km	278	°

As one can see, only signals from the most powerful transmitters were available with my shortwave antenna unpractical for this band. It's interesting that signals from the same region (Eastern Germany, Western Poland and Western Czechia) arrived at various hours that day (except for the bursts at 17.36 UTC). What is a reason? Exceptionally favourable for MS geographical location of the stations? Plenty of high-power transmitters in this region?

MS signals even interfered with Es ones at 13.02 UTC! The following waterfall illustrates the signals arrived by means of the two different modes of propagation simultaneously:

The second day of observations 14.08.2019 brought a lot of UNIDs and several IDed stations from the same European region as before:

11:14	92.00	MHz	POL	PR Radio Szczecin	Szczecin/Kołowo	60	kW	1130	km	293	°
11:14	92.20	MHz	D	MDR Sachsen (Dresden)	Dresden-Wachwitz	100	kW	1170	km	280	°
11:14	91.50	MHz	POL	PR 3	Lubań/Nowa Karczma	60	kW	1080	km	281	°
11:14	91.70	MHz	POL	PR 3	Częstochowa/Wręczyca	60	kW	820	km	278	°

All the stations were mostly identified by their playlists (fortunately, German and Czech broadcasters are accurately providing such information for special Internet resources), however RDS info and even direct voice IDs helped sometimes too:



RX: Airspy Mini
ANT: 80 mb dipole