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If you are interested in hearing radio station reflections off the meteor trails you are recording, audio output from the receiver can be recorded on VCR tapes or on standard audio tape decks. Care needs to be taken to use good quality tapes since poor quality tapes will contribute noise to the playback that can interfere with real signals.

Older VCRs that are not Hi Fi can be used but are not recommended. Sound is recorded on non-HiFi VCRs on the edge of the tape. If the tape has any kind of curl, bumps, roughness, misalignment etc. the head-tape contact is effected, and this causes a gain change. This makes the recording subject to fading, and noise pickup. Just flip open a tape cover (press the little rectangular pin on the left side as you look at the flap, with the tape face up) and look at the edge curl on a well used tape.  A good quality tape will be glassy smooth and uniform, but it's never perfect. The tape also moves up and down a tiny bit in the tape guides, and that is enough to misalign the tracks.

Tape recorders such as cassette tape decks or reel to reel tape recorders can also be used. The disadvantage of cassette decks is that the maximum tape recording time is around 1 hour. If you have access to a reel to reel system, recordings can run for many hours depending on the length of the tape. Some can be set to run at different speeds, making the recording quality and time vary. However, audio tapes do not allow time stamping with a video connection. It is possible to put the meteor audio on one track of a stereo system and a voice time stamp from a radio tuned to WWV (ask us about this if you want to try this option).

In order to get meaningful information from your meteor observations you need some means of transforming your observation into data. Audio recording may preserve the observation for playback but as yet this is not data. It must be converted to a usable format.

Several factors can be derived from the data.

1. The number of reflected signals per unit of time (usually per hour).
2. The duration of signals.
3. The amplitude or strength of the signal.
4. The audio characteristic of the signal (Doppler effect, etc.).

Data can be recorded in real time from the audio output by noting the factors above by hand.  Or it can be created using your recording of the observation after the fact. You can also record data in real time and record the observation using one of the methods described above. This has the virtue of providing a back up for cross checking information later.

Data recording can be done by a variety of methods. Each has advantages and disadvantages. Which method you use may also be dictated by the equipment you have available.

Our recommended solution is to download a copy of Radio Sky Pipe (RSP) which is distributed free of charge for individual amateur users from Radio Sky, a supplier of amateur radio astronomy supplies. If you have a sound card on your computer you can plug the output of your receiver into the Line input. RSP allows you to sample the signal from your receiver many times a second. Below are two sample meteor observation sessions using Radio Sky Pipe software.