Abstract: A bubble forming device for forming bubbles and thin film planes spanning the sides of a frame with bubble forming solution. The device includes an air inlet for forcing air into the device, for ejecting air into the thin films or extracting air out from the thin films. The bubble shape is dependent upon the shape of the frame (which may be formed from rods, wire etc.), between which the thin films span.

Abstract: A removable mold for forming high frequency antennae, such as a horn-reflector antenna. The removable mold may comprise a paraboloid-cylindrical section and a pair of half cone shells for forming respectively the paraboloid-cylindrical portion and the cone portion of the antenna. In assembling the mold, the shells are secured together and then the cylindrical section is fastened to the assembled shells. After the antenna has been formed, the mold is disassembled by first removing the paraboloid-cylindrical section, thereafter removing one of the shells and then the remaining shell; and all such mold parts being removed via the radiating aperture of the paraboloid-cylindrical portion of the antenna.

Abstract: A method for forming a high frequency antenna such as a horn-reflector antenna. In fabricating the horn antenna a mold may be used which comprises a paraboloid-cylindrical section and a pair of half cone shells for forming respectively the paraboloid-cylindrical portion and the cone portion of the antenna. In assembling the mold, the shells are secured together and then the cylindrical section is fastened to the assembled shells. After the antenna has been formed, the mold is disassembled by first removing the paraboloid-cylindrical section, thereafter removing one of the shells and then the remaining shell; and all such mold parts being removed via the radiating aperture of the paraboloid-cylindrical portion of the antenna.

Abstract: A control system for a product vending machine of any number of product selections(n) comprising a credit-device including a thyristor switch which is turned "on" after the proper amount of coinage has been accepted by the machine, to prevent any additional coin acceptance until after the product has been selected and released. Pulsating direct current (DC) is generated through a diode bridge when the thyristor is "on". During the vend cycle, an electro-mechanical product release mechanism controls a vend switch, which switches from a normal to a vend-position, to cause the credit thyristor to switch "off" and also to prevent the vending machine from accepting coins until the end of the vend cycle, when such switch is switched back to the normal-position. The product release mechanism may utilize either a motor-cam arrangement or a solenoid.