It is possible for amateur radio astronomers to detect some of the stronger pulsars by use of digital signal processing techniques even with a very modest antenna. We know of one amateur radio astronomer, Jim Carroll, who has detected 9 different pulsars using quagi antennas at 400 MHz! The trick to this is knowing the period of the pulsar in advance. We then sample the signal using a time base that is some integral fraction of the period. Each sample taken during the duration of a single pulse period is assigned to a bin. The samples can then be folded back so that samples from corresponding bins are added together.
Each time we add a new series of bin values for the ongoing totals, we "renormalize" by subtracting an an amount from all of the bins so that the weakest bin value is brought back to zero. Random noise in each bin tends to average out and bins which have even slightly higher averages will gradually "grow" above the others. A picture then emerges which shows how the average strength of the pulsar signal varies over it's period. We don't want to give the impression that this is an easy project. Jim Carroll is a very talented electronics engineer and developed a circuit with many integrated circuits to get his results. With modern micro controllers, ADCs, and DDS chips one might develop a less complex circuit to accomplish this goal. Still, very careful attention to detail will be necessary. If the observation is to be carried over a period of hours for maximum sensitivity it will be necessary to account for doppler shift caused by the Earth's rotation.
Amateur radio astronomer Jim Carroll, who has been doing this so long he has spouted an antenna.
The following links to .WAV files will allow you to hear the audio frequency modulation of radio noise generated by pulsars. If your .WAV file player has a scope function on it you will be able to see the regular nature of the waveforms. These files are quite long (some close about .5 meg).
CP0834 (very faint... for fun, try DSP on this one).
Discovering Planets in the Radio Sky How planets were detected orbiting around pulsars.
An Interview with Jocelyn Bell
Oleg Doroshenko has free timing and catalog software for pulsars.
Pulsar Newsletter homepage (Abstracts)
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