| Patent Number |
Title Of Patent |
Date Issued |
| 4631355 |
Telautograph system |
December 23, 1986 |
| The position (XY coordinate) of a pointed stylus on a conductive sheet is determined by injecting current from the stylus into the sheet and measuring the current responses at three or more spaced apart electrodes connected to the sheet. |
| 4519024 |
Two-terminal transistor rectifier circuit arrangement |
May 21, 1985 |
| A two-terminal rectifier circuit, useful for converting an input a.c. voltage into an output d.c. voltage, is formed by a power MOSFET which is provided with an electrical feedback comparator network designed to turn on the MOSFET once during each a.c. cycle when the input a.c. voltage i |
| 4440985 |
Apparatus for determining the location of faults in a transmission line |
April 3, 1984 |
| A toroidal, saturable core reactor (14) is connected in series with the conductors (11,19 and 13,21) of a transmission line. A termination network (16) is connected across the transmission line conductors (19,21). In response to an a.c. test signal transmitted from a generator (48) on on |
| 4349776 |
DC-to-DC Converters utilizing FET devices |
September 14, 1982 |
| Light-activated power FETs (18, 20, 80, 82) are utilized as switching elements in DC-to-DC converters. The FETs are characterized by high speed and low losses. As a result, the converters are capable of providing very low DC voltages in an efficient low-cost way. |
| 4319144 |
Single polarity circuit |
March 9, 1982 |
| A circuit with low impedance for maintaining a single polarity at an output is disclosed. Switching is provided by light controlled switching devices which in one embodiment are field effect transistors (14, 15, 16, 17) which are optically triggered by one or more photo-responsive device |
| 4228323 |
Variable loop length compensated barrier circuit |
October 14, 1980 |
| A gain and frequency compensated barrier circuit is disclosed for use with a telephone transmission line having variable loop lengths. A DC component of the input signal is provided to the input side of the barrier circuit. Loop length losses, as well as barrier gain variations, are adju |
| 4190747 |
Signal corrected optocoupled device |
February 26, 1980 |
| A remote gain controlled optocoupled device is disclosed utilizing a DC reference voltage in the output section to compensate for variations in the optocoupling characteristics of the circuit. The DC voltage level output of the photodetector, which is a function of the light transfer |
| 4137428 |
Optically actuated bidirectional semiconductor switch |
January 30, 1979 |
| An optically controlled bidirectional (bilateral) electrical switch is formed by a pair of photo-Darlington devices connected in series opposing (back-to-back) relationship between the two controlled terminals of the switch. Each of these photo-Darlington devices is shunted by a separate |
