Paul A Bauer

US Patent:

40229904, May 10, 1977

Filed:

Oct 28, 1975

Appl. No.:

5/626315

Inventors:

Paul R. Bauer - Palo Alto CA

Assignee:

Wiltron Company - Palo Alto CA

International Classification:

H04B 346

US Classification:

1791753F

Abstract:

A technique for measuring the value of a capacitance that is inseparatably connected with other circuit elements as part of a composite electrical circuit. The measurement is insensitive to such other elements that include resistances, inductances and active voltage sources. The technique involves the charging of the unknown capacitance followed by an immediate transfer of that charge to an external known capacitance that is part of an integrating circuit. The voltage stored by the known capacitance is unaffected by series resistances and is proportional to the desired electrical circuit capacitance being measured. The effect of induced or generated interfering signals in the circuit are cancelled by transferring the charge to the known capacitor for a period equal to an integral multiple of periods of the interfering signal. Furthermore, the charging voltage is adapted to the particular circuit in order to compensate for any resistance shunting the capacitance being measured. These techniques have a particular application to capacitive measurements of telephone communication lines.

US Patent:

39654184, Jun 22, 1976

Filed:

Mar 6, 1975

Appl. No.:

5/555727

Inventors:

Paul R. Bauer - Palo Alto CA
Duane E. Dunwoodie - Los Altos CA

Assignee:

Wiltron Company - Palo Alto CA

International Classification:

G01R 1704
G01R 1508

US Classification:

324 99D

Abstract:

Centralized telephone circuit testing equipment with receptacles for selectively receiving a wide variety of electronic circuit modules, various modules being provided to make the equipment capable of performing a large number of commonly employed telephone tests. A scanning system is disclosed as part of the central measuring equipment for determining which of a plurality of remote testing stations has requested access to the central measuring equipment, one requesting remote station at a time being given complete control over a test function of the central measuring equipment for conducting tests on a telephone trunk. Improvements are also disclosed in the individual test function electronic circuit modules, including common circuits for use in measuring both signal level and circuit noise, a logarithmic analog-to-digital convertor capable of handling signals that cross zero dBm in level, round off digital display circuits to improve accuracy of the display and to aid in calibrating the instruments, and an improved frequency measuring circuit.