Abstract: A method for detecting a fine frequency deviation generated in a transmission line such as a general public telephone switching network. The method includes the steps of transmitting test signals to a transmission channel to be tested, receiving the test signals from the transmission channel, detecting a basic period from the received test signals, and determining a measure period on the basis of the detected basic period, performing a normalization by use of the basic period determined, extracting values of signals to be calculated, namely, object signals from those of the basic and measure periods, calculating respective absolute values of the object signals, averaging the calculated absolute values, and thereby calculating an absolute value of frequency deviation and determining a sign or direction of the frequency deviation, and determining a final frequency deviation on the basis of the sign determined from the absolute value of frequency deviation.

Abstract: This specification teaches a method of attaching a fluid conducting metal tube (12) a heat dissipating metal fin (14) that includes the following steps. A metal tube (12) is formed having a generally elliptical cross-section having first similarly curved surfaces (22--22) at opposite ends of a major axis thereof and second similarly curved surfaces (24--24) at opposite ends of a minor axis thereof. A heat dissipating metal fin (14) is formed. An elliptically shaped collar (20) is formed on the fin, this collar providing an opening through the fin and being at least about 11/2 times the thickness of the metal forming the fin. The tube is fitted inside the opening of the fin so that areas of these two elements are juxtaposed. The tube is expanded along the major axis so as to bring the first similarly curved surfaces at opposite ends thereof into contact with portions of the collar in juxtaposition therewith.

Abstract: A six-cylinder swash plate air conditioning compressor having reciprocal double-acting pistons within a swash plate chamber positioned centrally between axially spaced front and rear cylinder blocks having intermediate suction and discharge gas crossover passageways in the cylinder blocks. The swash plate chamber provides a crankcase for receiving lubricant returned from the front head suction chamber by means of piston blow-by during the compression stroke of the pistons. The suction pressure in the crankcase is at a higher level than the pressue in the suction gas crossover passageway while being at a lower level than the pressure in the cylinder head gas discharge chamber creating the necessary positive pressure gradient to circulate the lubricant internally within the compressor.