Radio Meteor Observation Bulletin No. 13 September 1994 1. FORWARD SCATTER METEOR OBSERVATIONS Observer: M. De Meyere Location: Deurle, Belgium (3 37' E, 51 00' N) Frequency: 66.17 MHz Transmitter Locations: Katowice, PR3, Poland, 65.99 MHz, 14 kW, Distance 1100 km P. Neant, PR3, Romania, 66.17 MHz, 40 kW, Distance 1400 km Czestochowa, PR3, Poland, 66.23 MHz, 20 kW, Distance 1080 km Gdansk, PR3, Poland, 66.29 MHz, 40 kW, Distance 1100 km Antenna: crossed Yagi, 4 elements, Azimuth 270 o (=East), elevation 30 o Antenna amplifier: 25 dB max level 90 dBmuV Receiver: commercial, Progresson 447A, TESLA, Bratislava Sensitivity: 8 muV for S/N = 26 dB (300 Ohm) Observing method: automated setup, 150 samples/second, 8 bit resolution. [Time and details of all individual meteor reflections are stored on file in the University of Ghent format (Prometeos), and are available for further analysis. Reduction software for DOS and Windows available]. Raw counts of reflections with a duration of at least 0.027 s during one hour interval starting at UT: August 1994 Perseids Aug | 1994 | 20h 21 22 23 00 01 02 03 04 05 06 --------------------------------------------------------------- 1- 2 | 58 70 63 67 16% 5% 75 129 121 71 76 2- 3 | 56 63 63 49 1% 5% 95 111 94 48 54 3- 4 | 46 45 62 51 7% 4% 57% 78 102 42 47 4- 5 | 52 48 53 72 17% 1% 54% 83 66 56 53 5- 6 | 63 66 51 55 13% 3% 37% 136 91 67 79 6- 7 | 37 72 81 65 71 14% 19% 68% 107 100 70 7- 8 | 53 55 57 60 7% 1% 105 133 80 93 100 8- 9 | 67 95 68 71 24% 0% 114 129 143 107 - 9-10 | 80 91 99 59 39% 5% 73 152 90 116 102 10-11 | 60 106 60 71 52% 2% 120 158 136 142 105 11-12 | 69 84 68 93 10% 5% 82% 167 165 198 186 12-13 | - 142 107 110 73% 11% 95% 239 214 199 207 13-14 | - 110 95 97 100 68% 11% 30% 179 162 111 14-15 | 62 88 72 73 7% 0% 31% 102 89 79 64 15-16 | 79 69 56 44 4% 1% 52% 126 111 76 64 16-17 | 54 64 48 49 30% 0% 34% 86 66 88 86 17-18 | 73 82 57 57 6% 0% 52% 111 104 85 75 18-19 | 67 69 78 56 2% 3% 75 85 140 87 51 19-20 | 51 63 49 67 6% 1% 54 58 140 87 51 20-21 | 44 58 59 67 54 13% 9% 21% 81 90 67 21-22 | 48 64 48 45 2% 0% 40% 83 70 72 70 22-23 | 43 66 44 89 3% 6% 44% 92 70 74 54 23-24 | - - - - - - - - - - - 24-25 | 64 74 74 55 4% 6% 82 99 112 72 - 25-26 | 47 78 62 45 4% 3% 54 90 97 93 88 26-27 | 55 66 44 49 6% 13% 59 74 88 83 100 27-28 | 68 89 67 77 59 2% 3% 64% 120 95 68 28-29 | 80 65 53 47 40 2% 52% 93 94 97 78 29-30 | 39 42 60 49 26% 1% 25% 91 103 73 - 30-31 | 56 56 55 49 32% 0% 59 77 81 83 81 31- 1 | 55 66 57 56 9% 1% 41% 92 80 81 71 ------|-------------------------------------------------------- 1994 | 20h 21 22 23 00 01 02 03 04 05 06 Aug Aug | 1994 | 8h 9 10 11 12 13 14 15 16 17 18 ----------------------------------------------------------------- 11 | 106 102 89 140 102 82 63 66 34 73 56 12 | 248 349 313 229 186 139 132 157 94 112 139 13 | 215 250 144 & & & & & & 110 91 Notes: . % : transmitter outage during the whole hour or a part of it. Low counts indicate that no other interference, which could be confused with meteors, is picked up. Few transmitters are broadcasting between 2h-4h local time (Sat-Sun 3h-5h local time) or sometimes longer. (When summer hour is in use: local time = UT + 2h). . & : manually eliminated for direct reception. . The Perseids' new peak can be seen in the daytime data of Aug 12 between 8 h and 12h UT. Its intensity is lower than last year. This period of high activity is confirmed by Paul Vauterin, based on the observations at the University of Ghent, as well as by several radio- amateurs: "Maximum was on 12 August between 8h UT and 13 h UT. Jacques ON4AVJ (Belgium)." "Max activity during diurnal(?) peak, 12 Aug, around 11h00-11h30 UT. Silvio IW1AZJ (Italy)." "The 1st maximum seems to be at 12 Aug 09h-11h UT. A second peak was around 12 Aug 22h UT to 13 Aug 04h UT. Guido DL8EBW (Germany)." "For me the best activity was around 11h00 UT 12 Aug 1994. Jacob IC8FAX (Island of Capri)." Peter Brown reported a visual outburst on August 12, lasting from 9h30 UT to 11h00 UT (IAU Circular 6052 of Aug 12). The classical Perseid maximum took place on Aug 13 at 3h UT. M. De Meyere / C. Steyaert 2. PUBLICATION " World Radio & Television Handbook", 1994 edition, edited by Andrew G.Sennit, 599 pp., softbound. 1994 Billboard Books, ISBN 0-8230-5925-1, price approx 45 USD. BPI Communications, 1515 Broadway, New York 10036, NY, USA. This book contains country-by-country listings of long, medium and shortwave transmitters by frequency, time and language. Addititionally it provides the reader with information about: . world satellite broadcasts; . addresses of broadcasting organizations and DX Clubs; . receiver test reports. This book appears annually and is the major information source for identifying FM stations contributing to forward scatter. Jeroen Van Wassenhove 3. ABOUT THE RMOB The RMOB is an independent initiative of some workers in the field of radio meteor scatter observations and data reduction. It started in August 1993 in order to spread rapidly the Perseid results via E-mail. Since then, it has appeared monthly, and has gradually been expanded. Typically it contains: summaries of recent observations, first results of stream activity by radio methods, relations between radio and optical meteors, references to other publications in the field of meteor astronomy and radio scatter techniques, announcements of meetings, short questions and answers, non-commercial (second hand) sale of radio equipment, available software. Contributors are mentioned, and interested persons are asked to contact them directly. RMOB can be copied freely in unabridged and unmodified form. Extracts should indicate the source (Radio Meteor Obs Bulletin, month and year). If you want to subscribe (or unsubscribe) to the E-mail distribution list, please send a message to C. Steyaert. Those not having access to E-mail can obtain a printed copy free of charge from J. Van Wassenhove (current or backissues). 4. CONTRIBUTORS / USEFUL ADDRESSES Peter Brown Dept. of Physics, University of Western Ontario London, ON N6A 3K7, Canada tel: +1 519 679 2111 ext. 2111 E-mail: peter@canlon.physics.uwo.ca Maurice De Meyere Hullekensstraat 24, B 9831 Deurle, Belgium tel: +32 (9) 282 35 26 Call: ON4NU, packet: ON4NU@ON4AWP E-mail: via Chris Steyaert Chris Steyaert, VVS Kruisven 66, B 2400 Mol, Belgium tel: +32 (14) 31 51 04 fax: +32 (14) 22 13 73 E-mail: steyaert@vvs.innet.be Jeroen Van Wassenhove, VVS Working Group Meteors - Radio Section 's Gravenstraat 66, B 9810 Nazareth, Belgium tel: +32 (9)385 61 09 E-mail: 100101.734@compuserve.com Paul Vauterin, University of Ghent, Astronomical Observatory E-mail: paul@izar.rug.ac.be -- Christian Steyaert (RMOB9408) 6 September 1994 --