Abstract: A method for correcting higher order distortion introduced in a complex multifrequency waveform by an element which introduces signal-induced nonlinearities uses a replica of the non-linear element as a part of a high gain electronic feedback circuit between the output and an input of an amplifier. The replica of the non-linear element receives the multifrequency waveform, and is driven to duplicate the non-linear effects, which are used to generate a compensating voltage which is compared to the voltage obtained from the non-linear device. The resultant difference voltage after the comparison and amplification is then closer to the original signal. Thus, in an audio system for example, distortions which are audibly apparent to the human ear but so small they are immeasurable by instrumentation can be eliminated or minimized by employing a number of replicas in the same fashion.

Abstract: In a method of making a fluted core radome from resin impregnated glass cloth, an outer skin, a fluted core, an inner skin, an edge band and a drain cap are individually fabricated from plies of resin impregnated glass cloth which are laid up on a mold and then subjected to pressure using a vacuum bag and to resin curing heat using an autoclave. The fluted core is formed on a mold having recesses in the surface thereof by placing silicone rubber mandrels within the recesses and on top of the plies of glass cloth, the mandrels tending to expand in response to the application of heat thereto and at the same time tending to contract in response to the application of pressure thereto so that an equilibrium is reached which provides a tight fit of the glass plies over the mold and a relatively even flow of resin within the glass cloth.

Abstract: A retaining member (26) is constructed undersized from a memory metal for permitting a member (26) disposed in an element retaining position to recover and grippingly engage a stud (12) on which the member (26) is arranged. The retaining member (26) can be used alone, or in combination with a load-carrying nut (16) for greater strength. Providing a convex face (46) on the retaining member (26), and a concave surface (40) on the load-carrying nut (16), permits the total height of the arrangement to be limited to only slightly more than the height of the load-carrying nut alone in order to meet existing space limitations.

Abstract: In a process for continuously pulling a web of tows of carbonizable material under tension through an oxidizing oven, the web is introduced into the oxidizing oven by initially feeding a leader in the form of a web of heat-resistant cloth through the oven and then heating the oven if the oven is not already hot. The trailing edge of the leader which remains outside of the oven is then spliced to the leading edge of the web of carbonizable tows, and the leader is used to pull the web of carbonizable tows into and through the hot oven. Use of the heat-resistant leader greatly minimizes wastage within the web of carbonizable tows. Splicing of the trailing edge of the lead to the leading edge of the web of carbonizable tows is accomplished by taping, stitching and folding the two edges to form loops therein into which elongated rods are inserted. The two edges are then secured within a splice bar, the opposite halves of which define slots for receiving the two edges and the included rods.