Radio Meteor Observatory at www.radiodesignservices.co.ukRadio Meteor Observatory at www. radiodesignservices.co.uk

Introduction
Equipment

Results 2010

Geminids
Quadrantid

Results 2009

Geminids
Quadrantid

Results 2008

Geminids
Quadrantids

Results 2007

Quadrantids
Geminids

Results 2006

Geminids
Leonids

Results 2005
Quadrantids
Perseids
Draconids
Ursids
Geminids
Results 2004
Quadrantids
Perseids
Leonids
Ursids
Geminids

Results 2003
Aurora
Geminids

Results 2002
Perseids
Leonids
Ursids
Geminids
Links
Contact
Add to Favourites
 
 
 
 
 
 
Welcome

The aim of this site is to provide help for those wishing to get started in the detection of Meteors by radio. By showing the equipment in use here and providing links to other sites that have more detailed technical information I hope to show how relatively simple the set up can be.

First what causes the meteor sound you hear from the radio.

The ionized trail produced by the meteor momentarily provides a reflecting surface to radio frequency (RF) energy. This RF originates from a distant transmitter and is usually below the horizon and out of direct line of site of the receiving station. So the modulating intelligence of the distant transmitter is what you hear from your receiver, if it's a television transmitter you will hear a buzz, if it's a radio station you hear music or speech.

The general principle of meteor observations by forward scattering of RF energy off ionised layers caused by meteors

In the illustration above the general principle of meteor observations by forward scattering of RF energy off ionized layers caused by meteor trails can easily be understood.

Having looked at the general principal we now have to evaluate the requirements of the transmitter/receiver frequency, the distance of the path and its direction.

The frequency range most suited to meteor scatter lies between 40 and 110 MHz , above and below these frequencies other problems are encountered in the form of propagation and frequency limiting. So the meteor receiving station must be equipped with a VHF radio receiver capable of covering this range and, depending on the software to be used and the transmitters modulation, the ability to switch between different modes i.e. WFM, NFM, AM, USB and LSB. It should be noted that the mode of operation also governs the receiver sensitivity (bandwidth consideration) and hence the number of meteor counts.

Typically for a scanning receiver:

10 dB S/N -121 dBm USB/LSB
-97 dBm AM
12 dB SINAD -118 dBm NFM
-107 dBm WFM

Using the forward scatter principle the transmitter and receiver are at different locations and below the horizon due to the Earths curvature, so direct radio contact is impossible. This means that large distances are involved, typically 800 to 1600 km, and as with frequency above and below these distances other problems are encountered. If possible when selecting the path between receiver and transmitter a North - South path (or close to) is preferable.

Having decided on a frequency to use by selecting a transmitter in the right band and at a suitable distance the meteor counts have to be recorded.

Several methods are available:

1. Manual observations by listening to the receiver.
2. Recording with a pen/chart recorder thus giving a permanent record.
3. Probably the most common form is using a computer and software programme.

I have tried to keep all of the above information as concise as possible, more in depth reading material is available from the sites listed under Links, the IMO site in particular is a very good primer.