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Science Section => Radio Astronomy => Topic started by: Nomis Elfactem on 01:04:47, 25 July, 2014

Title: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 01:04:47, 25 July, 2014
I'll write this one up properly when I get a minute in the Projects board but after reading in the "How to" section of the Sky@Night magazine on how to build a basic radio telescope to capture meteor strikes I decided to give it a go.... well I've just been sitting here listening to the static for a couple of hours and truly amazingly I've heard and recorded over 30 strikes.... the screen shot below is of the best one of the night that I've just had and on the speaker it sounded like a cat meowing.... it clearly shows the Doppler shift caused by it moving towards (or away, I've yet to work it out) from me.

The setup the reflection off the meteor of a radar signal in Dijon, France so it's strange to think I'm hearing what the people in southern France are seeing.  The one I captured below must have been a belter !

Expect to see this board a little more active from now on (sad to see the last post on here was 3 years ago !!), especially as we're coming to the Perseids peak in the next couple of weeks !

... and the best part of all this... I can do it when it's cloudy and it's imaging of sorts :urock: :urock: :urock: :urock:

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: chris.bailey on 08:31:23, 25 July, 2014
Fascinating. Just a shame you can't see what makes those pings.

As you say, Meteor 11 must have been a belter.

Chris
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 09:13:02, 25 July, 2014
That's interesting Simon, by way of co-incidence I'm trying to set mine up again in the Obs. I suppose I will have to search around for new frequencies - I was using analog TV station carrier waves and I used to record from two good ones 24/7 over a period of about two years (last used about 12 years ago!). The interference from increased use of wifi stuff rather killed it trying to record from within the house, maybe I'll have more luck in the Obs.

Fireballs make for interesting traces,
(http://i970.photobucket.com/albums/ae183/ChrisLX200/capt47_zps36f82b59.jpg) (http://s970.photobucket.com/user/ChrisLX200/media/capt47_zps36f82b59.jpg.html)

and this is what the peak of the 2003 Quadrantids looked like on the two transmitters,
(http://i970.photobucket.com/albums/ae183/ChrisLX200/quadrantid_peak_24hr_zpsbf361c4c.jpg) (http://s970.photobucket.com/user/ChrisLX200/media/quadrantid_peak_24hr_zpsbf361c4c.jpg.html)

Anyway, good luck with the project :)

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 09:24:46, 25 July, 2014
Yeah, I agree mate about it being a shame you can't get a corresponding visual at the same time but at least I can do it when it's cloudy plus I've just kicked it off again and I've already had five little ones in the first 5 minutes and it's full sunshine  :urock:

I'm just about to order a long pole to mount the yugi aerial on but I think I'll have it as a portable set-up and (oooh, there's another one... see image below) I'll bring it to PSP in October  ;)

Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 10:15:53, 25 July, 2014
Wow Chris... that's a cracking trace.... who said analogue TV was rubbish !

What software were you using ? It looks like SpecLab but I only just installed it yesterday and all the config files came from S@N website so just getting my head around it. 

I'm currently viewing in 3D but not had a strike yet to get all excited about.  I'm also just trying to work out how I can record the audio output of the "pings"....

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 10:59:37, 25 July, 2014
Wow Chris... that's a cracking trace.... who said analogue TV was rubbish !

What software were you using ? It looks like SpecLab but I only just installed it yesterday and all the config files came from S@N website so just getting my head around it. 

I'm currently viewing in 3D but not had a strike yet to get all excited about.  I'm also just trying to work out how I can record the audio output of the "pings"....

S.

Yes that is SpecLab, but I used HROFFT and something else I can't remember the name of as well. SpecLab also output the audio files, but be warned - doing so takes up lots of disk space. This time of year there's of a lot of Spontaneous 'E' around which used to wipe out the trace during daytime (Heat of sun expands atmosphere leads to spont. E.). My old setup used to upload to the web to provide an real-time online monitoring service.

To be honest I'm struggling to setup SpecLab again myself, desperately rooting about for my old configuration files! I have the program files but the install together with my scripts were on another PC. I hope I don't need to start again from scratch.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: MikeDunn on 20:16:39, 25 July, 2014
What software were you using ? It looks like SpecLab but I only just installed it yesterday and all the config files came from S@N website so just getting my head around it. 
Just looked opn the site - I can't see anything about this ?  Can you provide a URL ?

Mike
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: PaulB on 20:42:45, 25 July, 2014
As Chris will tell you.
You can also record Aurora and Sporadic E.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 21:33:06, 25 July, 2014
Spontanious "E".... sound like an unplanned Friday night out on the town ;-)

Yeap, I had a feeling the audio recording would eat disk space faster than solar imaging... it saves a log file which gives the detail of each strike so maybe I'll have to live with that for now.

So a question Chris.... my trace above shows the trace signal moving from 3000Hz down to 2200Hz with the last part running along 2200Hz... reading the info then because I'm detuned from the actual frequency of the radar in Dijon by 2000Hz any received signal that is greater than 2000Hz is Doppler shifter away so indicates the plasma (meteor) is moving away from me so if I'm right a trace like the one above indicates a meteor that was moving away from me and the reason the trace move from a high frequency to a lower one is indicative of the deceleration as it burns up in the atmosphere. Am I reading that right ?

I also understand that a Doppler shift of 100Hz = 50m/s so when this meteor entered the atmosphere it was doing 500 m/s  (1,800 Km/hr).... awesome !

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 21:35:59, 25 July, 2014
Mike - I don't think there much about it on the S@N website... the URL for the config files is: www.skyatnightmagazine.com/cd/config.zip (http://www.skyatnightmagazine.com/cd/config.zip).  All the other info is in the June and July magazines themselves.

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: MikeDunn on 22:22:15, 25 July, 2014
Sad.

There was a time (pre sell-off ?) when the S@N site was very good ... no longer :(
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: swashy on 08:17:52, 26 July, 2014
Looks like fun
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Ian Straton on 19:08:44, 27 July, 2014

I also understand that a Doppler shift of 100Hz = 50m/s so when this meteor entered the atmosphere it was doing 500 m/s  (1,800 Km/hr).... awesome !

S.

I think you are an order of magnitude out, in your maths escape velocity for earth is 11km/s anything falling in from space must be going at least that fast, given that meteors are generally in orbit around the sun rather than the earth I would expect them to be going rather faster than that..
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 09:42:59, 28 July, 2014
I thought that too Ian but that's what it says on the picture in the S@N magazine.... I guess though that it all depends where upon the trajectory the signal originates from.... the diagram below shows that it's aimed to pick it up in the ionosphere (100Km+ height) so it could have slowed considerably before it is detected ?!?  Don't know ?!?

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 11:17:37, 28 July, 2014
Well you don't actually detect the meteor itself of course - just the cloud of ionised gas which is produced as a result of its passage, and that isn't going to moving anywhere near as fast.

PS, anyone got the frequency of that Graves Radar?

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 12:33:24, 28 July, 2014
143.05 MHz

 ;)

(indeed about the ionised trail  ;))
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Ian Straton on 21:31:52, 28 July, 2014
wonder if you could use RAF fylingdales or RAF Menwith hill for this? not sure if they are constantly transmitting in the same way as Graves is but could give a different angle for observation..
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Ian Straton on 21:37:29, 28 July, 2014
so Fylingdales transmits in the range of 420 - 450 MHz apparently, is that any use in the context of meteor gathering?
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Bazzaar on 22:33:47, 28 July, 2014
wonder if you could use RAF fylingdales or RAF Menwith hill for this? not sure if they are constantly transmitting in the same way as Graves is but could give a different angle for observation..

No, its the wrong type of radar. Graves only works for the purpose of meteor detection because it is a CW Doppler RADAR. Most RADAR are pulsed.
What is needed is a just a very powerful CW(not as in morse CW but constant like a beacon) transmitter. I'm sure people used to use things like eastern european VHF TV stations or FM broadcast transmitters back in the day. Graves is ideal but NOT due to it being part of any sort of RADAR system.

Barry
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 22:40:55, 09 August, 2014
Well I can't get anything from Graves on 143.050.000, maybe I'm just too far away from it.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 11:10:54, 14 August, 2014

Hi all,

Following this with interest.  I'm currently in the process of setting up my own SDR-Radio based detector, I'm hoping to have it working and looking for 'first ping' (can't really call it first light) within the next week or so.
 
I won't be making the antenna shown in the S@N article but will be using a borrowed 2M Ham Radio Yagi which is lighter and will be easier to mount.
(http://thumbs2.ebaystatic.com/d/l225/m/m1ZLUEriwKgpCUkJmyAm0pA.jpg)
I've  been told by the radio ham who is loaning me the antenna that I should expect higher signal gain from his antenna.  If it all works well then it only costs around £30 - £40 to buy one.
And it helps that my (very understanding) wife if far happier with a nicer looking, smaller antenna being mounted rather than the wood & copper pipe homebrew thing in S@N. 


I found a couple of pdf files that give a good overview of radio meteor detection using the GRAVES radar:
Here http://dk5ec.de/Graves-Echo-english.pdf (http://dk5ec.de/Graves-Echo-english.pdf)  and here  http://www.britastro.org/radio/projects/Detection_of_meteors_by_RADAR.pdf (http://www.britastro.org/radio/projects/Detection_of_meteors_by_RADAR.pdf)

I have a spare PC at home that will be used for this detector and the intention is to keep it running 24/7 using Spectrum Lab and Colorgramme to process the results. 
Obviously I'll want to take a much closer manual look at any bigger pings. 

I suspect there'll be a good bit of tweaking of the Spectrum Lab settings to get things right.Very interested in trying to see if speed & directional info can be obtained from the trace.
I'll be trying the S@N config files, but there is also some info & config files here on setting up Spectrum Labs 'conditional actions' to automatically count hits. (may be of use - but I can't vouch for it


Well I can't get anything from Graves on 143.050.000, maybe I'm just too far away from it.

ChrisH

I would think you should be able to hear GRAVES where you are. 
This website show regularly updated info from other detectors using the Colorgramme software (something I fully intend to use) http://www.rmob.org/livedata/main.php (http://www.rmob.org/livedata/main.php) (it auto refreshes every few mins)
Some of the UK sites are much further North than your location, at present there are a couple showing up around Newcastle and I've seen one in Scotland and they are using the Graves freq (143.050Mhz), so it may well be worth another try.


Cheers
   Al
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Bazzaar on 15:17:35, 14 August, 2014
Al, that's a good point about 2m ham antennas, the frequency difference isnt too great so they will work well and save people from all that plumbing to make one!
A word of caution about going for higher gain antennas, generally that means more directive and narrower beam width( think fov astronomers)
Go too far and you run the risk of having many of the meteors not being detected.
If your talking about 3 or 4 element arrays you should still be ok. Yagis are available up 14 elements or more! real monsters they are!

Barry
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 16:22:10, 14 August, 2014
Al: Be interested to hear how you get on with that 3el 144MHz OWL Yagi, maybe it's my discone that simply isn't up to the job. I did spend some time crawling the frequencies I used to use and did find a weak-ish carrier and a fair meteor scatter response, I thought I was in luck - but then it cut off at 12:15am! I checked again last night but not a peep out of it. If that antenna is successful then I may invest in one.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 21:31:37, 14 August, 2014
Al: Be interested to hear how you get on with that 3el 144MHz OWL Yagi, maybe it's my discone that simply isn't up to the job. I did spend some time crawling the frequencies I used to use and did find a weak-ish carrier and a fair meteor scatter response, I thought I was in luck - but then it cut off at 12:15am! I checked again last night but not a peep out of it. If that antenna is successful then I may invest in one.

ChrisH


> ChrisH:  I'll post on how I get on, but it now looks like it will be into next week before I get my hands on the antenna ... can't really complain as I'm getting to try it for free.

There is a guy on SGL from Middlesborough using a HB9CV 2 element Yagi and one of the cheap RTL-SDR dongles ( HB9CV means nothing to me but they seem to be common Ham antennas). Anyway he looks to be getting good hits using that antenna on the graves freq, so it's certainly achievable from the more Northern parts of the country (good to know as I'm in the Midlands).

http://stargazerslounge.com/topic/174881-cliffs-fireball-cam-radio-meteor-recieving-station/?p=1839214 (http://stargazerslounge.com/topic/174881-cliffs-fireball-cam-radio-meteor-recieving-station/?p=1839214)

There is a link to an audio of his detection .... I'd be very happy hearing those.

> Bazzaar  The Yagi I'll be borrowing is a 3 element. 
This one:  http://www.ebay.co.uk/itm/3el-144MHz-2m-Yagi-Shorter-than-HB9CV-and-Moxon-but-more-GAIN-SOTA-Portable-/290812885021 (http://www.ebay.co.uk/itm/3el-144MHz-2m-Yagi-Shorter-than-HB9CV-and-Moxon-but-more-GAIN-SOTA-Portable-/290812885021)  I'm tempted just to order one now, but trying to be patient!

Al
 
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 08:25:16, 15 August, 2014
Chris - when you say you can't "hear" Graves what do you mean.... also are you de-tuning to 143.048 as you need the 2khz for Doppler and have you angled it at 10deg to the southeast? Finally, my  yagi is from eBay as I didn't want a Heath Robinson... however even so and I've got the mounting poles my good lady doesn't want it visible in the garden. I see a roof mounted Arduino project coming.... so many project... so little time.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 08:54:33, 15 August, 2014
Chris - when you say you can't "hear" Graves what do you mean.... also are you de-tuning to 143.048 as you need the 2khz for Doppler and have you angled it at 10deg to the southeast? Finally, my  yagi is from eBay as I didn't want a Heath Robinson... however even so and I've got the mounting poles my good lady doesn't want it visible in the garden. I see a roof mounted Arduino project coming.... so many project... so little time.

Hi Si,
I mean I see nothing on Spectrum Lab, and I have tuned either side of the nominal 143.050.000 during the peak of the Perseids so if there were anything I would have been sure to see it. I've recorded meteors before, for 2 years 24/7 from a variety of analog TV carriers, so I know what to look for. I feel it must be the Discone (which is omni-directional) and I need the extra gain from the Yagi, I just don't want to buy one without being confident it will work for me. I have two iCom PCR1000 receivers that I used for this job and they still appear fully functional and they tune accurately. The old E. European analog TV transmitters were outputting 450Kw not the 10Kw of Graves.
Chris
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 22:24:23, 15 August, 2014
Sorry Chris, didn't mean to teach granny to such eggs... can only go on my limited experience and as you can see I picked them up from Graves with a 3 element yagi.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Bazzaar on 22:37:30, 15 August, 2014
I would suspect the discone too Chris.
Great aerials for general tuning around over a wide frequency range, but for a specific task maybe lacking.
Unless its 30 meters up with a masthead amp?
Barry
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 23:14:56, 15 August, 2014
Sorry Chris, didn't mean to teach granny to such eggs... can only go on my limited experience and as you can see I picked them up from Graves with a 3 element yagi.

Not at all Simon, it was a reasonable question. I don't know much about radio at all, just enough for me to set up and run my old meteor scatter setup. But in the past I used frequencies between 45 - 60MHz and had a huge signal to work with, so with a 20-fold weaker signal at 143MHz maybe the Discone simply isn't the tool for the job.

Barry, the antenna is on a 4 meter mast and no amp, can't go any higher really. I know to get the best gain out of the Yagi it should be 10 metres off the ground.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 14:04:11, 17 August, 2014
Another thing I find with this (new) Obs PC I'm using, there's a lot of random noise in the trace which seems to originate from the PC itself, probably the rubbish on-board sound chip. If I disconnect the audio input from the receiver most of the noise is still there! I guess I'll need to invest in a half-decent sound card offering better noise isolation. On my home desktop PC I used previously it was equipped with a Creative soundcard and it performed pretty well, but I didn't buy that card specifically for the job. If I do have to buy one for the Obs PC I'll be looking for one with the best s/n specs. Anyone been down this path and bought one for the job?

ChrisH

Edit: I spotted an Xonar Essence STX on offer on OCUK so snagged that, it may do nothing for the radio meteor observations but my music will sound better :)
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 16:17:42, 18 August, 2014
Chris - one thing I noticed is that the noise varied depending upon which USB socket I used for the dongle.... with one of them it made the whole set-up un-usable :(

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 18:39:29, 18 August, 2014
Chris - one thing I noticed is that the noise varied depending upon which USB socket I used for the dongle.... with one of them it made the whole set-up un-usable :(

S.


Ah yes, USB ports are not well shielded, and the front (or extension) ports are worse because they use un-shielded connecting cables running inside the PC case which will pick up all kinds of RF. I'm using discrete receivers which are earthed outside to a 1metre copper pipe hammered into the ground, and the audio output uses a single shielded cable to connect to the audio input on the PC. Everything is fine up to that point! The only other connection between PC and receiver is a good quality RS232 control cable.

I'm only using one receiver at the moment:

(http://i970.photobucket.com/albums/ae183/ChrisLX200/Astro%20-%20Autofocuser/DSC00449_zpsb40134d2.jpg) (http://s970.photobucket.com/user/ChrisLX200/media/Astro%20-%20Autofocuser/DSC00449_zpsb40134d2.jpg.html)

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 21:03:32, 18 August, 2014
Have you tried receiving a signal from that FUNcube-1 satellite? I'm just tracking it now and waiting to see if I can detect a signal from it :)

(http://i970.photobucket.com/albums/ae183/ChrisLX200/Astro%20Shed/DSC00455_zpse66423be.jpg) (http://s970.photobucket.com/user/ChrisLX200/media/Astro%20Shed/DSC00455_zpse66423be.jpg.html)

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 21:24:38, 18 August, 2014
I haven't yet Chris, no.... on the list of things to do next week when I've got the week off !!

Happy hunting and let us know how you get on !

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 15:03:12, 19 August, 2014
Well still no meteors on Graves, and no lock on the FUNcube-1 satellite, but I think that is down to the Discone antenna and I'm beginning to wonder if it works at all... On a more positive note the new sound card is brilliant, the amount of background noise is a tiny fraction of what it was when using the on-board sound chip. I think with a new 4E Yagi antenna I should be set to go.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 12:16:04, 25 August, 2014
Today I ordered a new antenna, this one: http://www.ebay.co.uk/itm/290812915938?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 (http://www.ebay.co.uk/itm/290812915938?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649)
which I hope will work better for radio meteors using the Graves Radar beacon than my Discone. Have to wait and see. I can't mount it at the required height (30ft) for maximum gain but luckily there is a gap pointing SE so it should still work. I hope.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 18:55:18, 31 August, 2014

After a bit of a delay with the antenna I finally got my meteor detector set up last night.
No meteor pings yet but I can see other signals so I'm fairly sure the antenna, cabling and software are all working.

I have loaded the S@N meteor scripts and have a question ......  Can anybody tell me why a frequency of 143028khz is included in the script ?

The GRAVES radar transmits on 143050khz, the instructions say to tune to 143048khz. But any screen captures report 143028khz (as below) regardless of the actual freq set:
(https://dl.dropboxusercontent.com/u/14166007/FCDscript1.JPG)

Looking inside the script itself, in the [CAPTURE] section it says:-
 
     InfoDef0=$"Date="+str("YYYY-MM-DD",now)
     InfoDef1=$"Freq= 143028 kHz"
     InfoDef2=$"Config = MetScat_starter_v1"

I understand the reason for actually tuning 2khz below to allow for an audible ping, but is there a reason the script is designed to report a freq 22khz lower than that of graves?


Al

Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 19:29:07, 31 August, 2014
I should get my new antenna either tomorrow or Tuesday, already got a new cable made up ready for it (although the antenna will need assembling because it arrives as a kit). I don't know where the 143.028 comes from but yes, you're using SSB (single side band), either USB or LSB which is offset from main carrier frequency. Maybe it was a typo as you could put whatever you want in there and it would make no difference to the capture.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 11:53:26, 01 September, 2014

It looks like the 143028khz doesn't make any difference. 
It is listed in the [CAPTURE] section of the S@N scripts and it seems it just adds text to the screen capture info box, so I think it's just a typo and can be changed to anything ......
..... Perhaps something like the correct freq!

It certainly doesn't make any difference to detection as I caught my first 2 pings last night .... only small ones but at least I know it's working.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 16:05:05, 04 September, 2014

I now have my detector working (although some bits still need tweaking!)

Rather than sit waiting for a meteor hit I wanted to prove out the antenna, dongle and software .....
(https://dl.dropboxusercontent.com/u/14166007/AeTest1.jpg)
  :D Well I'm happy thats all working, so back to the meteors....

Eventually I got SpectrumLab working and capturing meteor hits. I started with the script supplied by the Sky at Night mag and that's not designed to do everything I want it to do so it will need some changes.

But I did start seeing some hits:
(https://dl.dropboxusercontent.com/u/14166007/event140902024018.jpg)

Where I started having problems was in automatically counting the hits overnight and then uploading/displaying that info.  With a little help from a couple of people I have now managed to get Spectrum Lab to count up the hits then Colorgramme Lab (http://Colorgramme Lab) collects that and uploads in to the Radio Meteor Observing Bulletin (RMOB) website which then gives this readout:

(http://217.169.242.217/rmob/livedata/live_datas/Grant_092014.jpg)

It needed some different Conditional Actions from those in the S@N script. 
It's a great way to see the number of hits over a period of time and far more convenient than manually counting screen shots each morning!
I still get a screen grab for each hit but I'm only keeping the better ones.

The results I'm getting seem to be in keeping with those reported by other UK/Northern Europe sites using the Graves Radar (143.050Mhz).
My results should update more frequently once I get some wifi connection issues sorted (hopefully tonight)

I still need to make changes to the scripts and there is a guy on the RMOB website who has very kindly offered to try help (otherwise it would take me forever) and also to help me make sense of some of the more unusual non meteor captures.

So at the moment it's working, I'm getting regular hourly hits on the Graves freq, but my Spectrum Lab setting are still in need of some tweaking in time for the next big meteor shower.



Al

Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 17:40:20, 04 September, 2014
Well you're having more luck than me Al, apart from a couple of small pings early on which were just enough to convince me it was all working great. However, I'm not seeing much at all now. Everything _seems_ to be still working correctly I'm just not getting the hits I would expect to see (like, completely blank for a couple of hours...). This is with the 4el OWL Yagi which is pointing horizontally SSW, receiver set to 143.049.800 USB, tried narrow (3k) and wide (6k) filter, I've also tried with/without the digital noise suppressor filter circuits activated (that cleans up the spotty background and allows me to crank up the volume to get better definition). So I'm at a bit of a loss where to go next with this.

ChrisH

Edit... Whoa, wait, wait, wait... looking at your trace I see you're getting a response way up at 2000Hz and I'm only looking up to 1300Hz. I've just changed Spectrum lab to monitor the higher frequency and I immediately see the trace of an aircraft - that can only be from Graves. I think. OK, I'll try again with that setting.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 17:58:20, 04 September, 2014
Chris - it says to point the Yagi up at 10deg... not sure if having it horizontal is causing trouble ?

Just a thought...

S.
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 18:01:51, 04 September, 2014
Chris - it says to point the Yagi up at 10deg... not sure if having it horizontal is causing trouble ?

Just a thought...

S.


Ah, good point Simon. I should do that (but see above also...)

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 20:45:09, 04 September, 2014
Well I'm still seeing nothing. I'll try tipping the antenna up 10deg tomorrow (not as simple as it sounds, will need to fabricate a new bracket of some sort). I cannot see that making the difference between seeing or not seeing some pings though.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 21:18:36, 04 September, 2014
Well I'm still seeing nothing. I'll try tipping the antenna up 10deg tomorrow (not as simple as it sounds, will need to fabricate a new bracket of some sort). I cannot see that making the difference between seeing or not seeing some pings though.

ChrisH

Chris,

I have my antenna at a very slight angle, but I don't think it's 10degs.

As for my trace being at 2000hz, well that's down to the setup that S@N advised to use rather than anything I decided upon. 
They say that tuning to 143048, 2khz away from the actual graves freq helps reduce noise. 
Spectum Lab sets everything up automatically when running their script.

This is one of the things I want to look at and tweak in the future.  But it's working, so I'm not complaining!

In fact just as I'm typing this a nice bright one popped up and as I had my speakers on I got a really nice loud ping. 
Think I'll need to look at enabling the audio capture as well now, but that means more digging around in Spectrum Lab.


(https://dl.dropboxusercontent.com/u/14166007/Meteor20140904200529x.jpg)





Al
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 22:50:46, 04 September, 2014
I'm running out of ideas on this. 5hrs and nothing, made a a few adjustments along the way but quite limited in what I can change because it's a very simple setup really. With no responses at all I cannot tweak anything to improve things. I know the equipment is OK (and I have two receivers and tried both). So I'm packing this in as a bad job I think.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 07:19:58, 05 September, 2014
Chris - have you tried tilting the Yagi ?  The reason is that it points at the part of the sky that the signal will come from with Graves pointing south and the meteor trails beeing at X thousand feet up in the atmosphere gives an angle of 10deg from mine and the guy who wrote about it latitude (he worked out the trigonometry). I too only have a horizontal bracket which is why I haven't set it up permanently yet but when I got it working I had it sat in the opened jaws of a work bench which pointed it up slightly. It' was not at all scientific but I did get differing hit rates at different angles...
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Nomis Elfactem on 07:26:50, 05 September, 2014


PS. My understanding is the the detune of 2khz is due to the doppler effect of the moving ion trail. Depending upon which direction it is moving relative to us will set it's detection frequency ? I could of course be talking rubbish but that's what I read .

Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 11:41:39, 05 September, 2014
Chris,

Sorry to hear you're still  having problems.

Not being anything like an expert on this I can only assume that your antenna/receiver are all OK and you can see other signals OK, which obviously proves your hardware.

What direction do you have the Yagi pointing in and is it horizontal or vertical ?   

I've seen some posting that horizontal can help reduce interference, but generally the advice for Graves seems to be to go vertical.

The S@N mag said to point it to the S.E. 
Initially I just pointed it to the SE and didn't see very much (which is what got me questioning that 143028 freq) I then checked the bearing from my location to Graves using this website  http://www.sunearthtools.com/tools/distance.php (http://www.sunearthtools.com/tools/distance.php)  and I needed to be more between 145-150 degs. 

I did notice a difference after this small adjustment, I can only assume that has to do with the directional properties of the Yagi (unless it was something else I changed).  Using that website it looks like your location is pretty much along the same bearing as mine. Mine is currently around 148 degs.  Depending on the direction yours is pointing, would a few degrees would make a difference?

Not sure if you've tried the loading the S@N script into Spectrum Lab, doing so sets a number of configs options and a bandpass filter which can be seen using the 'Components' menu. 
Even after that there were a couple of things I needed to change in the settings before I actually got to see anything (like actually selecting my Dongle as the Rx source!). 

When I get home I could let you know the settings I currently have and pass you a copy of the script if you want to give it a try.


Al
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: ChrisLX200 on 12:42:37, 05 September, 2014
Thanks Al, I'm as sure as I can be that the hardware is working OK, the receivers tune correctly, and yes I can pick up other signals just fine. The only thing I can think of is that I'm simply not getting the Graves signals into the receiver, either because the Antenna is not pointing in quite the right direction (difficult to believe it is THAT directionally sensitive) or the fact I have intervening trees to line of sight which interfere. My old Discone antenna used to be located in my loft so that had line of sight of precisely nothing but it still worked fine. I've tried both my older version of Spectrum and the newest version with the supplied scripts, I prefer my older version because I've written a lot of custom scripts which save data and screen dumps (and also audio if I want), and whilst the newer version has a few more bells and whistles it is otherwise the same. It isn't Spectrum failing to display correctly, you can _hear_ the characteristic pings when you get them over the speakers and they just aren't there. I've tried tuning slightly off-band above and below, USB and LSB, various filters wide and narrow, there's just nothing. If there were even the faintest of traces to work with I could tweak various settings to improve things, but when there is nothing at all you can't do a lot. I will try adjusting the antenna later but I don't have an alternative location other than where it is, so only directional changes. I've tried a range of horizontal bearings between SSE and ESE. The busiest time for meteor pings (when there is no shower) is always in the mornings, it tends to be pretty quiet around 6 in the evening, but even then I would expect to see a couple dozen small hits per hour. Maybe I'm expecting too much after being spoiled with the responses I used to get.

ChrisH
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 14:05:46, 06 September, 2014
Hi Chris,

No idea, I'm getting decent hits and am not really that far to the SE of you.
Not sure about the trees, there are a row of houses just to the back of me in the direction my antenna is pointing.

Can't think of any reason why you're not getting anything - Hopefully you manage to get it sorted.

I'm trying to get the automatic audio trigger set on mine so I can capture a few pings, but not having much look with the trigger at the moment .... a bit of 'trial and error' should sort it!

Al
Title: Re: Meteor Radar SDR Receiver (usnig FUNcube dongle)
Post by: Al.Grant on 11:51:02, 04 October, 2014

Have now managed to get my meteor detector settings sorted out and running fairly stable, apart from one occasion when Spectrum Lab locked up.

Have my audio capture sorted.  Thanks to a modified script somebody sent to me I now have Spec Lab set to count all meteors for the RMOB site, but only take screenshots and audio capture for the longest (duration) and brightest (highest s/n ratio). 

I've also made a quick website ( http://www.ukstargazer.org/meteor-detection/ (http://www.ukstargazer.org/meteor-detection/) ) and the screens are auto uploaded.   

I'll probably drop the 60 sec waterfall traces, they work and are useful for me to quickly check if it's all working when I'm at work.  Hit/miss if there's actually anything on the screen.
I've had a quick look at Spec Labs audio streaming, but not got anywhere near getting it working!


Al


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