Mufax chart recorder type D-665-C manufactured by Muirhead and Co Ltd. The Mufax chart recorder is used on ships for receiving meterological maps and wire photos by radio. In this machine, audio signals are converted to current pulses which pas through a helix, acros the paper to the writing edge. Each time a current pulse is applied to the helix the paper is marked, so that when when scanning is complete, a clear image is produced.
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