Gregory Weng Yuen

Title: Gregory Weng Yuen: Innovator in Variable Capacitance and Transformer-Coupled Circuits

Introduction

Gregory Weng Yuen is a notable inventor based in Harlow, GB. He has made significant contributions to the field of electronics, particularly in the development of variable capacitance circuits and transformer-coupled mixer circuits. With a total of 2 patents to his name, Yuen's work showcases his innovative approach to circuit design.

Latest Patents

One of Yuen's latest patents is a variable capacitance circuit. This invention provides an improved variable capacitance circuit that is substantially linearly controlled using voltage or current control. The circuit comprises two emitter connector transistors and a constant current source or drain, forming a current steering circuit. A fixed capacitor is connected to the emitters of the transistors, creating a port into the circuit. AC current flows through the fixed capacitor and is fed back through the transistors in a proportion that depends on the voltage at their bases. The effective capacitance of the circuit is varied using this variable AC feedback arrangement. Other embodiments utilize current control to adjust the circuit capacitance by varying the effective constant current source level.

Another significant patent by Yuen is a transformer-coupled mixer circuit. This circuit includes a DC voltage supply and four transistors, arranged as two pairs. Each transistor pair consists of a first and a second transistor, with each having a base, collector, and emitter. The emitters of the first transistors in each pair are connected to the collectors of the second transistors in the same pair, while the emitters of the second transistors are connected to a current sink. The circuit also features a transformer with primary windings and two sets of secondary windings. The outputs from these secondary windings are 180 degrees out of phase, and the primary windings receive an input signal. The bases of all transistors receive local oscillator signals, ensuring that only one transistor pair is activated at a time.

Career Highlights

Throughout his career, Gregory Weng Yuen has worked with prominent companies such as Nortel Networks Corporation and Northern Telecom Limited. His experience in these organizations has contributed to his expertise in electronic circuit design and innovation.

Collaborations

Yuen has collaborated with various professionals in his field, including his coworker Peter John Mole. Their joint efforts have likely led to