A phonic wheel generator for position indication in digital computor magnetic drum storage
D R Quested, ANDREW D. BOOTH · Journal of Scientific Instruments · 1954
A brief account of the requirements for position indication on a magnetic storage drum is followed by an elementary discussion of the expected output from a variable reluctance phonic wheel generator at frequencies in excess of 20 kc/s. This investigation leads to experimental designs of generator, the output of which agrees, in order of magnitude, with that calculated. Finally, the system in practical use at Birkbeck College is described.