Meteor Detection via GRAVES - Trying to get it to work...

[PhotoGav]

Thanks to a very kind hearted soul on here, I have an aerial and a Funcube Pro+ dongle to try and detect meteors using the GRAVES radio frequency. Initial set up is in progress and of course, it's never quite as simple as I would like, though I had never expected it to be easy! I hope that you will be able to help me in my journey.

The aerial is built and the FCP+ is connected to the PC. I am using FCHID2 to tune the FCP+ and have set it to 143048 kHz. I have that feeding into Spectrum Lab v2.95 with the settings file downloaded from the Society for Popular Astronomy's Radio Meteor Observing set up guide (https://www.popastro.com/main_spa1/meteor/radio-meteor-observing-2020/). First of all I tested the set up on a radio station frequency using the settings from Paul Hyde's old Sky At Night article (https://britastro.org/sites/default/files/BBC_SatN_HOWTOOBSERVEMETEORS.pdf) and it checked out ok, with the waterfall showing bright and full lines. The signal generator in SpectrumLab creates an event on the waterfall too. I reverted to the meteor detection settings and let it run over night. Here is the temporary set up in my office, you will see that the aerial is carefully aligned to 130º azimuth and 17º altitude!

 

 

To my amazement it has registered quite a few events in the event log. An example line is: "03:09:17, 2, -82.5, -89.6, 2316.3, 2", needless to say I am not totally sure what those numbers mean. As far as I can work out they are: event time stamp, don't know, max amplitude, min amplitude, frequency, duration. Is that correct? There is also a folder in the Spectrum folder called 'screenshots' which has a collection of screenshots, though it doesn't have one for every event in the event log. The problem is that the screenshots don't appear to show anything for the meteor event beyond a text label. Here is an example:

 

 

It looks like the event I detailed from the event log above is 'Meteor 2' in the screenshot, but how come I can't see any associated 'ping' on the waterfall? I guess it is probably a settings thing, but I have next to no clue what all the settings are in Spectrum Lab, so any help at all would be greatly appreciated.

 

Thanks,

Gav.

[Tomatobro]

It did take me a while to figure out all the settings. To check out everything I would just use the SDR waterfall to start with and don't forget to set the gain on the dongle (about 25 is ok for my system). In the early days I used Bandicam to record half hour sessions of the screen and next morning scroll though each AVI to see if I captured something.

If you have one of those gas lighters that emit a spark when the lever is squeezed then that should give you an artificial signal to test the system 

[PhotoGav]

14 minutes ago, Tomatobro said:

It did take me a while to figure out all the settings. To check out everything I would just use the SDR waterfall to start with and don't forget to set the gain on the dongle (about 25 is ok for my system). In the early days I used Bandicam to record half hour sessions of the screen and next morning scroll though each AVI to see if I captured something.

If you have one of those gas lighters that emit a spark when the lever is squeezed then that should give you an artificial signal to test the system 

Thank you, I’ll look at the gain setting and give the lighter trick a go!

[wxsatuser]

Get the ant outside and lower the elevation.

 

[PhotoGav]

7 minutes ago, wxsatuser said:

Get the ant outside and lower the elevation.

 

Thank you - I did wonder whether I was shooting myself in the foot by keeping the antenna inside!

[Tomatobro]

I am on my other laptop and have attached my SDR settings list which might help. This is using the free software SDR-radio

dongle set.txt

Edited November 2, 2020 by Tomatobro
update

[PhotoGav]

29 minutes ago, Tomatobro said:

I am on my other laptop and have attached my SDR settings list which might help. This is using the free software SDR-radio

dongle set.txt 670 B · 1 download

Thank you for that - I will have a detailed look and compare with my settings.

I have connected to the FCD by SDR# and I can definitely pick up Radio 2 (the second round of Popmaster is what I heard!!), so that is good. I have altered the gain to 25 and the waterfall in SpectrumLab now looks better in that it has blue specks in it. The lighter spark trick was registering in SDR# too, though not showing up in SpectrumLab. I am now just waiting for a meteor to be detected...

Thank you for your help so far.

[Tomatobro]

I see the setting you have is 143028 khz which I suspect means that the data is displayed off the screen. I use 143048 khz. (The Eyes are the first to go they say)

[PhotoGav]

1 minute ago, Tomatobro said:

I see the setting you have is 143028 khz which I suspect means that the data is displayed off the screen. I use 143048 khz. (The Eyes are the first to go they say)

Well spotted, though the frequency was always set to 143048 kHz, but the text used for the frequency display in the screenshot was set to 143028 kHz - I have changed that now.

[wxsatuser]

11 minutes ago, PhotoGav said:

Thank you for that - I will have a detailed look and compare with my settings.

I have connected to the FCD by SDR# and I can definitely pick up Radio 2 (the second round of Popmaster is what I heard!!), so that is good. I have altered the gain to 25 and the waterfall in SpectrumLab now looks better in that it has blue specks in it. The lighter spark trick was registering in SDR# too, though not showing up in SpectrumLab. I am now just waiting for a meteor to be detected...

Thank you for your help so far.

You most likey want to see speckling on the waterfall as this is noise.
You would expect the receiver to pick up various noises, so don't have a black water fall.

[Tomatobro]

my first ever image of a meteor. I remember pointing at the screen in a state of excitement saying to my wife "look at that, LOOK AT THAT!"

That's very good she said, now what would you like for your tea.......

[wxsatuser]

When I used to do meteorscatter on 2metres it was always exciting waiting and then receiving the pings and bursts.
Sometimes one burst would complete a contact other times it would take a whole hour off pings, you just never knew
what would happen.

[Tomatobro]

And the ISS and a meteor together.  Scary stuff

[wxsatuser]

Direct signal and a local sprog at 2000hz

Direct signal plus a burst.

Several pings on the trot plus a direct signal, sprog at just over 2000hz

Satellite with direct signal plus aircraft running off the main direct signal.

[PhotoGav]

Oh My God... we have a hit (I think!)...

This looks far more as I was expecting - is this a meteor?

 

 

[wxsatuser]

Are you recording the sound, if so it should be easy to tell.

[PhotoGav]

11 minutes ago, wxsatuser said:

Are you recording the sound, if so it should be easy to tell.

Oh gosh, if I am I have no idea where to!

[wxsatuser]

You may have wave files, have a look in the directories to see if there are any.

I know my SL did wave files.

Edited November 2, 2020 by wxsatuser

[PhotoGav]

1 minute ago, wxsatuser said:

You may have wave files, have a look in the directories to see if there are any.

I know my SL did wave files.

There was nothing there, but I have ticked the triggered wave files output option. Hopefully that will record the next event. 

What will a meteor sound like?!

[wxsatuser]

Sound depends on if it's a ping or burst and how long.

Pings can range from a click to a wheeeee with doppler, bursts are similar but longer may be with doppler
and a warbling type of sound.

They are mostly unmistakable, when you hear them you will know.

[PhotoGav]

OK, thank you. It just registered another small event, but didn't record any sound... back to the settings!

[Ibbo!]

Here is a good one I got from my old Yupiteru, the USB dongle is not so goods so far.

Turn volume down first.

Meteor20160802134859.wav

[wxsatuser]

Yes thats a nice one.

[PhotoGav]

39 minutes ago, Ibbo! said:

Here is a good one I got from my old Yupiteru, the USB dongle is not so goods so far.

Turn volume down first.

Meteor20160802134859.wav 515.79 kB · 3 downloads

Thank you Steve, yes, that is pretty clear! Were you using Spectrum Lab to capture?

[Ibbo!]

9 minutes ago, PhotoGav said:

Thank you Steve, yes, that is pretty clear! Were you using Spectrum Lab to capture?

Yes I was, it used to work fine but I am struggling with it this time around.That one was on the old PC and from 2016.

I got the dongle last year and fiddled with it and could not get it to work so it went in a box.

I am in the process of decorating and during the tidy round re- discovered the dongle (any excuse to avoid the D word) and this time I got it working but am struggling as it only giving a short "ping" , the sound is difficult to pick from the background mush and SL is not picking it up on the conditional actions.