|
22A1. General description. At the time this
book was written, a new type of underwater
log was in process of development. This log
is known as the All s-Chalmers underwater
log, and is manufactured by the Allis-Chalmers Manufacturing Company of Milwaukee, Wisconsin. The rodmeter element
of the system consists of a small propeller,
in the hub of which is placed an a.c. generator.
The propeller head is secured to a bronze tube
with provision for inserting and removing
|
|
through a 3-inch sea valve. Leads from the
generator are brought up through the rodmeter tube to an electronic amplifier which
in turn drives a small synchronous motor. A
mechanism interprets the synchronous motor
revolutions in terms of knots and nautical
miles. Remote indicating stations are driven
by the usual synchromotor system. Preliminary tests of these electronic logs give
promise of extremely high accuracy even at
low speeds.
|
