unknown strong reflection 

during the meteorshower “ursids” i run a qso with clubstation OZ3FYN.  during the last periode (73) of receiving, i have noticed a reflection, never seen bevor. here the facts and pictures.

station: OZ3FYN - EDR Odense Branch ( in qso with OE1SMC )
locator: JO55EJ (QRB 902 km, QTF 335° direct way)
date: 2009/12/22 21:43:00 UTC
software: WSJT mode: JT6M
type: unknown scatter, band: 50 MHz / 6 m
meteor shower: ursids

in this case i show you the SpecJT window too:

oz3fyn_jt6m_small_size

and below the main-window of WSJT

oz3fyn_jt6m_3_main

my first impression, as i heard the sound in the headset and see the image on the wsjt-screen: “wow, a big overdensed meteortrail” but then i looked, it isn’t like a typical overdensed one. over the years i have seen a lot of overdensed ionisations, so i would say, this reflection isn’t such one. what else ? an aircraft reflection. with 10 km in high you cannot reach more than 700 km distance and our QRB was 902 km. a tupolew Tu-144 in 18000 meters could solve this problem, hi. but this one is also not typical for an aircraft reflection. it is too short and i looked with spectrum lab, there is no doppler effect. of course, this must not be, if the aircraft direction is in the right angle to our direction. for me this type of reflection is still today unknown.

i assume that the left site, and therefore the beginning, started in the same way as the right site, the finish. the vertical line in the left is due to incompatible clock settings between our computers. oz3fyn’s computer started a little bit later to TX as my computer started to decode.
in later periods i have noticed some atypical noise levels, as seen at the right upper quarter in the SpecJT window too.

one of the operators of OZ3FYN was Bjørn OZ6OM. he is, imho, one of the great 6m-operators worldwide with a lot of meteorscatter experience. i asked him for his opinion. here is his answer: 

Hello Hans

First the best whishes for the New Year
Further, Yes I did recieve Your mail of Dec. 23rd.

- and I looked thurelly into it, without coming to any evident conclution.
I agree, the signal looks different than the usual reflection, especialy it seam equal strong in most of its length, with a more steep end than usual.
I have looked at Air coridors and flights above 30000 ft. However I have found that with the Earths curve and more than 950 Km. between our stations, Airplane reflectios is not likely (an exeption would be a military flight).
Next thought was, what if the altitude was higher. For example a low orbiting satelite. I tried to find data of satelites passing at our QSO time, but on the other hand satelites with a very low, is not nessesarely know with Kepler data open for the public.
But as neither of those theories are easily confirmable ...
So until further I will call it an unknown strong burn, and wonder what kind of material will cause such a intence ionisation.

Kind regards
Björn


finally here the wave-file produced by wsjt.

if you have any ideas about the phenomenon described above, please be so kind to inform me, send me an e-mail or post an anonymous comment in my guestbook. i hope to read your infos. i am sure, the explanation is easy.

oe1smc 1/2010

Powered by EasyCMS