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From the indo - Irish skies set to host a clestial fireworks display

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    #62
    Stargate
    Registered Users Posts: 2,680 ✭✭✭Stargate


    Dave! wrote: »
    These visible again tonight? :o What direction?

    Dave look here

    http://science.nasa.gov/headlines/y2009/images/geminids2009/skymap_north.gif

    More or less SE , but you better off just looking overhead as they will shoot in all directions coming from that point near Gemini .

    Wish ya luck !! ;)


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    #63
    Stargate
    Registered Users Posts: 2,680 ✭✭✭Stargate


    Anyone want to try this tonight ......

    " Yes, in principle you can listen to meteor echoes using a broadcast receiver on the FM band. The complicating factor is that the VHF Band II spectrum (FM Band) is pretty congested and the bandwidth of the domestic receiver is very wide. This makes it difficult, but not impossible, to find a suitable bit of spectrum. It'll be a lot easier in remote locations and more difficult in densely populated regions. So, it'll be a lot easier from the north of Scotland, or north-west Ireland, than from the midlands say. You'd probably struggle to find a suitable frequency if you are in a major conurbation.

    What you are looking for is a frequency with no local transmitters, but a strong distant transmitter. The first criteria is the difficult one, if you can find a quiet local channel, then the chances are that there will be something on it somewhere in Europe, or beyond. To reduce interference from adjacent channels, switch the receiver to mono, if you can.

    If you find a suitable quiet channel, and you un-mute the receiver, you'll just hear white noise (hiss). Then, assuming there is a strong distant station on that channel, a meteor reflection will generate a burst of programme material. You may even receive the RDS (station ident) data during a stronger reflection. It is a common misconception that you'll hear "pings". You'll not hear pings using a FM receiver to listen to an FM transmission. You only hear "pings" using a single sideband receiver to receive an unmodulated carrier.

    The only thing to do is give it a go. I'd suggest trying 105.0 MHz for starters and see how you get on. There are a couple of low power stations locally, but there wasn't anything powerful the last time I looked - a couple of years ago.

    One disadvantage of this method of radio meteor detection is that the detection is difficult to automate. Computers aren't good at distinguishing programme content from white noise. This is one reason that the majority of radio meteor observers use a scanner, or communications receiver, rather than a broadcast receiver. One solution is to modify the receiver to give you access to some indication of signal strength and use the computer to log this and automatically detect increases i signal strength. That's a more advanced subject though and may require agreement from the other half, before you pull the stereo to bits... "

    http://www.popastro.com/phpBB2/viewtopic.php?t=13027&sid=2e3108223bfc25cc113b7a30e4de224f


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