Mike German

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Viewing 20 posts - 1 through 20 (of 25 total)
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  • in reply to: Total success from Mena, Arkansas #622510
    Mike German
    Participant

    Thanks for sharing your images with non-globe trotting entusiasts!

    in reply to: EU Conference on Radio Astronomy EUCARA25 #621886
    Mike German
    Participant

    Please correct me if I am wrong but I think this is the The European Conference on Amateur Radio Astronomy (EUCARA) not the EU conference

    in reply to: Radio Astronomy Meetings #621192
    Mike German
    Participant

    Hi Andy,

    “It could be useful for someone to add these to the main events page. Each meeting takes a bit of work to setup, so it is a non-trivial task to set them all up and maintain them. There is also a minor issue that as there are so many, setting them up would knock some other upcoming meetings off the list on the homepage. Something for the Web Ops Group to think about.”

    Yes I agree that would be useful/

    in reply to: Summer Meeting Nottingham University – Parking #611137
    Mike German
    Participant

    Hallo Andy,
    Thanks for finding the information for me.
    Regards
    Mike

    in reply to: Booming sounds across Dorset, Somerset, and Devon #583980
    Mike German
    Participant

    I use GRAVES transmitter and received 15 meteor events between 1430 and 1530 UTC yesterday, 20/3/21. The largest of these was at 15:07:19 and the signiture was that of an underdense meteor with a head-echo. The duration was 0.37 seconds.   On a subjective assessment the recieved scatter signal was moderate for me in Derbyshire and nothing special.   

    Updated after seeing IMO page which makes it earlier than my event.  I guess the geometry wasn’t rignt for scatter for my location.

    in reply to: Geminids 2020 GRAVES Radar detections #583592
    Mike German
    Participant

    Mark,

    I too welcome the opportunity to compare methods and results. What is your location?  I am in Hayfield in the Peak District.  Here is my colour chart from one of the systems.

    Filtering non-meteor events from the logged data is a tricky one; I select and reject using calculated characteristics of each event.  For this system over 30% were rejected or which many were probably meteors.  

    I think one reason I may have relatively high count rates is because the FFT in the capture and logging program provides higher resolution in time (~10ms) rather than in frequency; this detects shorter duration meteors than, say, Spectrum Lab set-ups normally do. 

    The antennas in the vertical configuration do not utilse the maximum gain; I has mast head LNAs to provide a little boost to the signals. 

    Mike 

    in reply to: Geminids 2020 GRAVES Radar detections #583590
    Mike German
    Participant

    Bill,

    it is not part of windows it is an app that you should be able to find with a search enigine.  I have sent a BAA email with the address.

    Mike

    in reply to: Geminids 2020 GRAVES Radar detections #583585
    Mike German
    Participant

    Bill

    I have had a PC and laptop used for RA stuff running 24/7 for 3 months or so – the secret is using something like “Stop Updates 10”; it does what it says!

    With regard to the antennas, two are show in my picture, shown against a pink sunrise. They are, to give them their full title,  cross polarisation 3 element LFA (Loop Fed Array) Yagis (Red and Green systems). The antennas are completely separate electrically. They point vertically and the elements point 45 degrees either side of GRAVES bearing.  They are very much an experimental arrangement and the idea is that because the patterns in this orientation are ( I believe) akin to a dipole (exact modelling or measurement is a problem ) there is some direction discrimination.  The other antenna is a 2 element LFA in traditional horizontal polarization configuration (Blue system).  I am fairly sure GRAVES transmits vertical – certainly their recieving array are verticals so that would account for the better performance.  

    Mike

    in reply to: Geminids 2020 GRAVES Radar detections #583575
    Mike German
    Participant

    These are all interesting measurements Tracey and Bill. Also interesting the individual approaches we take to capture and display our data.

    Here are counts from my three experimental antenna systems.  On the 13th the highest count is in the hour starting 21:00 UT and on the 14th the peaks are in the hour from 23:00. (NB total counts without allowance for sporadics)

    I note from the BAA Handbook the predicted maximum was 13th at 20:00 which I calculate as corresponding to a solar longitude of 261.995 which compares withe IMO listing of the 14th with solar longitude 262.2.  (sorry, I can’t work back to UT) At my location the maximum radiant elevation was at around 02:00 UT on both days

    Mike

    Hayfield, High Peak

    in reply to: -5.4 exploding fireball #582681
    Mike German
    Participant

    I have written a note this on  event for my own records.  It compares the video data with radio data.  The results are useful but no firm conclusions can be drawn, so I won’t copy it here. However, if you are interested in the note and give me your email I will send it (I have shared it with a couple of observers already.)

    Regards

    Mike G

    in reply to: -3.4 southeast fireball #582605
    Mike German
    Participant

    Ernie/Stan

    Location: Hayfield, Derbyshire

    in reply to: -3.4 southeast fireball #582575
    Mike German
    Participant

    Interesting shots – keep them coming.  Unfortunately radio meteor monitoring was alas off line at that time.

    Mike

    in reply to: Meteor LiveStream #582539
    Mike German
    Participant

    John,

    As others have said, great idea. Will raise inerest in radio meteor observations.  Great advestising for BAA-RAG – perhaps links to that website for practical how-to-do advice.  BTW I even saw your water pump leap into action!

    A banner running across the screen every so often with BAA-RAG link 🙂

    in reply to: Meteor LiveStream #582525
    Mike German
    Participant

    As far as I am concerned it is running along absolutely smoothly. Watched it for 5 minutes  or so and saw one small meteor event – wrong time of day, I will have a look in the morning. We come up to the Maximum of the Daytime Arietids (171ARI) on 7th with possible ZHR of 3 – that should be worth looking at.  

    Incidentally what settings are you using on Spectrum Lab to get a 30 second sweep.

    Regards

    Mike

    in reply to: -5.4 exploding fireball #582494
    Mike German
    Participant

    Thanks for direction Nick.  This is definitely useful information in helping me extend what I know of the coverage of GRAVES radar. The scatter is from lobes from the rear of the antennas. The end of the trail crosses the Great Circle line between my monitor receiver and the transmitter close  to Dijon and is just about midway between.  The power profile I recorded suggests it is  specular scatter which, because of where, implies it is at a fairly shallow entry angle.

    Thanks again Nick and Eric – keep them coming!

    in reply to: -5.4 exploding fireball #582483
    Mike German
    Participant

    BTW Nick is the direction SE or NW?

    in reply to: -5.4 exploding fireball #582480
    Mike German
    Participant

    Hallo Nick and Eric 

    Not as far N as originally though but all usueful information – thanks

    in reply to: -5.4 exploding fireball #582473
    Mike German
    Participant

    Nick and Americo 

    It would be most useful if you do that – thanks!

    in reply to: -5.4 exploding fireball #582470
    Mike German
    Participant

    Is there any confirmation of the flight path please?  As a radio meteor observer using the GRAVES radar it is not often that I find a video capture with trajectory that correspond to a radio event. This is important because the coverage of the radar is largely unknown.  If this were over Kent it would be the futherest North I have had!

    in reply to: -5.4 exploding fireball #582466
    Mike German
    Participant

    Here is what was captured in Hayfield, Derbyshire using a radio station tuned to GRAVES with Spectrum Lab

    and here is the Doppler shift and power profile from  Meteor  Logger 

     

    There is no head echo but it otherwise looks like a classical overdense power profile. 

     

    Mike German

    Hayfield in High Peak

Viewing 20 posts - 1 through 20 (of 25 total)