Graves Radar - Radio Based Meteor Detector

[Al.Grant]

I've now just about got everything working so that meteor detections automatically get counted and the info is uploaded/displayed on the Radio Meteor Observing Bulletin (RMOB) website using Colorgramme Lab.  

 

I still have a couple of things I want to change and am talking to somebody from the RMOB website who has offered to help with SpectrumLab scripting and to help identify some of the more unusual (non meteor) hits that crop up.

 

 

 

This at least gives me a decent overview of detections over time, I'm also getting screen grabs for each detection but only keeping the better ones.

 

Looking at other UK detectors in the UK/Northern Europe the figures I'm seeing are fairly typical.  http://www.rmob.org/livedata/main.php    The map marker in the centre of the UK is me!

 

I've got a bit of a wifi connection problem where my PC is situated and the connection keeps dropping but I'll soon have that sorted and it does a full update when it does get a connection.

 

 

Really looking forward seeing the levels detected during the next meteor shower

 

 

Al

[Daz Type-R]

That is pretty impressive Alastair, keep us updated on your progress.

 

Edited September 4, 2014 by Daz Type-R

[Al.Grant]

Here is a link to a Perseid Meteor

 

http://www.thehykehamobservatory.webspace.virginmedia.com/Meteor20140812190615.wav

 

You can work out the date and time from the title of the file.

 

The rest of the web page is still under construction.

 

Phil

 

Hi Phil,

 

Can I ask what settings are you using for your audio capture ?

 

I'm trying to set up the audio trigger to automatically capture  but think I've got something wrong on the trigger point.

 

I'm going through various option on the 'save input' or 'save output'  and various trigger sources (L1 or L5)

 

I'm getting decent live audio but want to capture those hits in the early hours.

 

 

Cheers

    Al

[Al.Grant]

That is pretty impressive Alastair, keep us updated on your progress.

 

 

Getting a good number of meteor detections throughout the day.  The most active periods are from midnight though to about 9am.

Most are small pops, pings and whistles producing small dots on the spectrum lab waterfall display,  but there are a few each day that are just a bit more impressive.

 

These are fairly typical of the bigger ones each day.  

This was from earlier this morning  (cropped to reduce size)

 

This one from yesterday was loud enough and long enough that we heard it from the front room (with the TV on) and the screen capture missed the first few seconds

 

 

And another:

 

 

Although it's all working, I'm getting a bit frustrated trying to get the audio trigger set so that it captures the bigger ones overnight.

I can switch the audio capture on/off manually, but that's not practical but not having much luck with the trigger at the moment and leaving it on all the time isn't an option as the uncompressed audio files are far too big!

 

 

Al

[Guest HykehamObservatory]

Hi Al,

 

I am not sure which version of the script you are using- the one you found or the one I sent. You are finding the same problem as I did- this thing uses vast amounts of harddrive space. I adjusted my script to only record the images of the larger meteors. I will look at adjusting the audio trigger for the larger ones as well.

 

Phil

[Al.Grant]

Hi Al,

 

I am not sure which version of the script you are using- the one you found or the one I sent. You are finding the same problem as I did- this thing uses vast amounts of harddrive space. I adjusted my script to only record the images of the larger meteors. I will look at adjusting the audio trigger for the larger ones as well.

 

Phil

Hi Phil,

 

I'm currently using the version you sent me (thanks again for that) with a small edit to change the Low/High values in line 3 from LOW=1100:HIGH=1450 to LOW=1500:HIGH=2500.  Threshold is still at 17

 

Do those Low/High values need to be changed anywhere else?  I couldn't see anything obvious, but I'm only just (slowly) starting to get to grips with the scripting.

 

With that script loaded I saved the settings as a .USR file. I think I'll go back through that just to make sure nothing was set elsewhere in SpecLab that would conflict with the audio or the M_BIG values.

 

I'm assuming that in your version of the script the M_BIG value of >3 is the Dur value.  

So it triggers only on a Dur greater than 3 - is that correct ?  <====  Edit: Just realised this is wrong!

 

 

 

I did also add an hourly meteor counter to one of the unused buttons  "Meteor/Hr"+str(COUNT_HR)  this simply show how many detections during the current hour and resets on the hour, but that shouldn't interfere with anything. 

 

It would be great if the audio automatically triggered on the larger ones.

 

I had looked at using the periodic/scheduled action to only turn the audio trigger on overnight when there is a greater chance of catching something worthwhile, but just detecting larger meteors would be far better.  However at the moment my problem is it's not actually triggering automatically.

 

Your help would be hugely appreciated and may just save me from too much more of this   

 

 

Cheers

           Al

Edited September 8, 2014 by Al.Grant

[Al.Grant]

Hmmm  maybe I've been looking at the wrong thing here.  

I've got the script to capture audio files but the problem seems to be the actual sound level once recorded, the audio through the speakers is fine.

 

I moved the wav files over to my laptop and listened to them and can hear a very (very, very, very) faint ping in the back ground. Even having the gain turned right up doesn't seem to make a difference. 

[Guest HykehamObservatory]

Hi Al,

 

I have updated the script and it now only saves jpeg and wav files for large meteors. It does however count all the meteors. I can send it if you wish. One hour today it recorded 40 pings but only saved images and sounds for three of them- much better for the laptop hard drive. In the version I sent you M_BIG only controls the Image recording (>3 spectrum lab cycles). You do only need to adjust LOW and HIGH on one line.

 

There are basically two volume controls for the radio- the laptop volume and the gain in Spectrum Lab. Spectrum Lab works on the audio output of the dongle. I have the laptop volume set to about 10%. Go into Spectrum Lab  'Components'-'Show Components'.  I have L1 set to 22dB. Mixer Enabled 'USB down converter'. Filter- you will need to adjust this to your centre frequency. L4 set to 22db. Output Amp- use this as your volume control. Mine is set to 5db on one computer and 12dB on the other.

 

Incidentally the brightest meteor I have recorded hit at 2-45pm today. The laptop speakers were not happy- S/N 46dB

 

Regards

 

Phil

[Al.Grant]

Hi Phil,

 

That sounds great.  Yeah I'd love to get hold of a copy of your script it that's OK.

If possible could you send me the script and also I'd be interested if you could try a 'Save Settings As ...' and send .USR file which as far as I know would have all the circuit config in there as well.  

 

Then I can try loading that to see if everything works.  My basic config was set with the S@N script, but now I'm loading different conditional actions  I want to be certain there are no conflicts.  Then I'll do a 'restore factory settings' on Spec Lab to clear out anything I've been messing with and reload.

 

Thanks for the audio level info, I'll have a good look through at my settings and hopefully I'll get this sorted.

 

Really appreciate the help !

 

 

 

I picked up this one in the early hours of this morning ... not particularly long, but would have been loud enough!

 

 

No surprise that I wasn't around to hear it  

 

 

Cheers

     Al

[Guest HykehamObservatory]

Hi Al,

 

I am working on the problem of this radio detecting all sorts of rubbish as well as meteors. I know you have the same problem. I would be interested in what percentage of your meteor count have a Dur=1. My script now discards these and only counts meteors that last a minimum of Dur=2 (one second).

 

Incidentally, I think your trace of 7th September could be a tumbling satellite. I have picked it up as well and it lasts at least ten  minutes which is far too long for a meteor.

 

Phil

[Al.Grant]

Hi Phi,

I'll have a look  and see if I can get a figure for them, but I do get a number of Dur=1 hits.

 

Interesting about that 7th Sept trace and your thoughts do make sense.  I had taken another look at it and thought it couldn't be a meteor.

The trace looks far too regular, if you measure the blocks and the line between them they are the same length.  

I easily can see how a tumbling satellite could account for this regular pattern.

 

I think I'll get Orbitron up and running on the same PC to see if there is anything that coincides with these sort of hits.

 

 

............ Now if only I could get my audio issue sorted  

 

Al

[Al.Grant]

Hoooray 

 

Finally have my audio recording/playback problem sorted.  Now getting nice screen shots and wav files to match.

Set to only record the bigger hits, rather than every small ping.

 

Al

[stash]

[Guest HykehamObservatory]

Hi Al,

 

Well done with the sound problem. I have been working on the problem of false meteors being recorded. I have set:

TESTA to <10 not <6

TESTB to >1.5 not <7

 

It gives me nearly 100% correct counts for DUR=1 meteors.

 

Did you capture something between 10-15 and 11-15 am yesterday? It caused mayhem with my meteor count- up from around 30 per hour to 230 in that hour. It drifted into the beam. Stayed at the same Doppler frequency, then stopped an hour later. I can only think of some sort of balloon.

 

One question. How did you get your Colorgramme plot out of Colorgramme? I want to save it somewhere else and not just on the RMOB site.

 

Regards

 

Phil

[stash]

Wow  balloon's get picked up  - I presume there are more likely to be the weather type balloon's not the kid's party type? 

[Al.Grant]

Hi Al,

 

Well done with the sound problem. I have been working on the problem of false meteors being recorded. I have set:

TESTA to <10 not <6

TESTB to >1.5 not <7

 

It gives me nearly 100% correct counts for DUR=1 meteors.

 

Did you capture something between 10-15 and 11-15 am yesterday? It caused mayhem with my meteor count- up from around 30 per hour to 230 in that hour. It drifted into the beam. Stayed at the same Doppler frequency, then stopped an hour later. I can only think of some sort of balloon.

 

One question. How did you get your Colorgramme plot out of Colorgramme? I want to save it somewhere else and not just on the RMOB site.

 

Regards

 

Phil

 

 

Hi Phil,

 

Sounds good.  I've just logged in to my home PC on Teamviewer and changed those TEST values to give it a try.  

 

I didn't get anything unusual yesterday.  No screen captures and no unusually high meteor counts.

A few days ago I did have a single hour overnight that reporting over 300 hits, way above my usual counts.  I check first on RMOB to see if other UK sites had seen exceptionally high readings .... they hadn't, so I'd clearly had some sort of interference.  This threw the colour plot on colorgramme out having a single 'red' square and everything else 'blue', so opened the RMOB data file and changed that result to something below my normal levels.

 

 

As for the colorgramme image.  I just link to my readout on the RMOB site        http://217.169.242.217/rmob/livedata/live_datas/Grant_092014.jpg

It displays the colorgramme plot and as it's based on the live data it updates when a page is refreshed.  

So the image I posted here on 4 Sept will be displaying the latest data I uploaded.

 

You can also link to the text version of your data, which also updates on a page refresh:  http://www.rmob.org/livedata/live_datas/Grant_092014rmob.TXT

 

 

Actually just thought that I should be able to add it as a forum signature .....  let's see!

 

Al

 

Edit:

Yeah that works!

Edited September 17, 2014 by Al.Grant

[Al.Grant]

Here's an image and audio capture from this afternoon:

 

Audio (.mp3)  https://dl.dropboxusercontent.com/u/14166007/Meteor20140917130735.mp3

 

 

 

 

Al

[Guest HykehamObservatory]

Do we have any spaceflight members? I am trying to identify something in my radio detector. If you look at Al's post of 8th September you will see an on/off regular pattern in an object in his radio detector. This object has been frustrating me for some time.

 

Yesterday the object appeared in my Meteor Detector at a frequency of 1340Hz at 12.28pm. The Doppler slowly fell- so it was coming towards me, until it reached 1080Hz at 16.15pm by which time it was going away from me. It rotates about every five seconds but there is another 90 second amplitude change in the signal. There is only one of these objects so I am guessing on a large rocket rather than a satellite. It has to be in a high orbit as it stays in the radar beam for so long. I think the orbital period is just over 24hrs but I may be wrong.

 

Does anyone have a clue as to what it is?

 

Phil

[stash]

Only a guess but could it be the Russian rocket going to Space station

 

http://www.space.com/17933-nasa-television-webcasts-live-space-tv.html

 

 

Or Space X

 

http://www.nasa.gov/news/index.html#.VCW5UmddVqY

 

ISS a bit crowded 

 

http://www.nasa.gov/content/expanded-crew-relaxes-after-busy-week-of-docking-activities/#.VCW57mddVqY

 

Doesn't meet Al's bleep though

Edited September 26, 2014 by stash

[Guest HykehamObservatory]

Hi stash,

 

Thanks for the reply but it can't be that low. ISS goes across the sky in a couple of minutes. This object takes many hours. It has to be in something much further out like Geostationary orbit- or a very elongated orbit that goes that far out.

 

Phil

[stash]

OK Phil thanks for the reply - very interesting. So would a "close" passing  space rock  show up on your detector so long as it "ionises" in the earths atmosphere ?

Edited September 27, 2014 by stash

[Al.Grant]

Hi Phil,

 

I've no idea what it is.  I'm seeing a number of oddities ("Can you hear me major Tom" ... Sorry wrong sort of space oddities!) crop up on the display, some seem quite regular others less so.

 

I've created a directory and am moving any screen shots that I think are non-meteor noise to that directory, in the hope of detecting pattern on times of day etc.  When I eventually get a personal website sorted out I may put a selection up online to see if anybody recognises them.

 

I see an almost constant, strong signal at about 3700hz. Can't track down what it is, I think it's local interference but as it's not impacting on the meteor detection counts or screenshots it's not a major issue.

 

 

I got quite a large detection this morning at about 08:09 but that was on a freq that ties in with my meteor detections.

 

 

Al

[Guest HykehamObservatory]

Please remember the Graves system is for low Earth Orbit satellites- and bigger objects further out. It just happens to be useful for ionised meteor trails as well.

 

Al, I saw your object as well at 8-08am this morning. Biggest trail I have had for a few weeks.

 

I am up and sort of running at www.lincolnastronomy.org/phil/  I seem to have an occasional upload problem. Its OK at 2 minute intervals for hours and then suddenly it can't confirm my username or password and stops. I need to restart the upload programme and off we go again. I am uploading , the longest and brightest meteors since midday and the current waterfall image every two minutes.

 

Al, If your not sure about an object -see if I have seen it. If it is big and the waterfall has stopped, it will still be on the harddrive. I have M_BIG set at 10 now.

 

Phil

[Al.Grant]

Liking the live website update Phil 

 

I'm going to look at my setup a bit closer in a couple of days.  Mon/Tues we have workmen in fitting a new boiler, central heating pump and shower, so expecting lots of drilling and general turmoil.

[Al.Grant]

my Radio meteor detector caught this nice long hit earlier this morning:

 

 

 

A real pity that meteors detected using the Graves radar can't be seen visually from the UK.

I'd love to be able to detect a meteor via radio, audio and all sky cam, but would need to try HF detection on the Brams transmitter (49.9Mhz) for that one and that would need a much bigger antenna ..... even then no guarantee it would work from my location.  Seems better suited to South of England.

 

Al