The INSCO 6503A series of single tachometers are servoed
replacements for "drag magnet" tachometers. These beautifully
designed and updated tachometers really perform. With greater
accuracy, smoother operation and elimination of friction and
position errors, the 6503A series offers maximum reliability. In
fact, many INSCO 6503A series tachometers have been in daily service
in 1972, and today's design is greatly inspired from that of the
6503A operates from either a standard 2 or 4 pole tachometer
generator, or from a magnetic pulse (monopole) transmitter. The
indicator is entirely self-contained, requiring only 28 volts DC
power, and a frequency (speed) input).
It is available with or without a Vernier pointer, and has specified
accuracy of + / - 0.5% F.S. It is also available with an overspeed
or underspeed warning lamp on the dial, and connector contacts for
remote warning functions.
The 6503A has been designed with maximum reliability in mind. There
are no punched gears or bushings in an INSCO gearhead. We use
precision machined close-tolerance aluminum and stainless steel
gearing, and every gear shaft runs in ABEC7P miniature bearings. All
electronic components are selected with a wide 'cushion' to prevent
premature failure, and much of the circuitry is hybridized into a
custom thick-film circuit.