Disclosed is a base drive circuit that provides a base drive current particularly adapted to switch a switching power transistor ON and OFF quickly. The base drive current includes a variable AC impedance device that responds to a control pulse to form a base drive having (a) an initial forward base drive peak that drives the switching power transistor toward deep saturation momentarily, followed ...

1. A method for providing a vertical deflection saw tooth signal to a TV set associated with a video tape recorder from a frame synchronization signal provided by an integrator (21-23, C1), characterized in this that it comprises the following steps : - interrupting the operation of the frame saw tooth generator from the occurrence of the frame synchronization signal (ST), - from this time, or aft...

Two harmonic mixers arranged in parallel are connected to a first signal frequency gate and to a second local frequency gate by means of a single radiofrequency hybrid circuit in quadrature or by means of respective hybrid circuits of which one in quadrature and centered on the signal frequency and the other in phase, quadrature or opposition of phase and centered on the local frequency. Another i...

A method and apparatus for providing an indication of a cardiopulmonary activity of a person using noninvasive monitoring means and for detecting motion in the area of the apparatus includes an electrostatic charge detector for providing an output signal including signals indicative of motion and cardiopulmonary activity of the person. A detection apparatus is connected to receive the signals and ...

A dual mode peristaltic device is provided for infusing I.V. solutions to a patient through an I.V. tube. In a first mode of operation, the device functions as a peristaltic pump and in the second mode of operation it functions like a controller. Included in the device and associated with the I.V. tube is a pressure sensing strain gauge assembly that monitors dimensional changes in the outer diame...

A process for the manufacture of iodine, in the presence of a catalyst selected from copper, gold, a transition metal or a compound thereof, characterized in that an aqueous solution of an alkali metal iodide is oxidized-with oxygen, air or other oxygen containing gase-in the presence of carbon dioxide (an alkali metal carbonate and/or bicarbonate being thus formed). Iodine is generally obtained b...

In a method and apparatus for liquefying material such as glass batch, primary thermal protection for the vessel is provided by a lining of the batch material, with secondary protection being provided by forced cooling of a minor portion of the vessel in regions and at times when the primary protection is irregular.

A resin composition exhibiting improved resistance to environmental stress crazing and cracking comprising: (i) a blend containing at least one aromatic carbonate resin and at least one grafted derivative of an ethylene-propylene-diene terpolymer; and (ii) an amount effective to improve the resistance to stress crazing and cracking of said blend of at least one multiphase acrylic interpolymer of a...