Method and circuit for determining the presence or absence of at

Details Method and circuit for determining the presence or absence of at Method and circuit for determining the presence or absence of at

1986-09-24

1987-05-26

Tokar, Michael J.

Electricity: measuring and testing

Measuring, testing, or sensing electricity, per se

Analysis of complex waves

324 79R, 328 14, G01R 2316

Patent

active

046689109

ABSTRACT:
A method and circuit for determining the presence or absence of a frequency of known value in an input signal composed of several frequencies employ a frequency generator, to which a stable reference signal is supplied, for generating two switching signals having a frequency which is the same as the known frequency and a phase difference of 90.degree.. The input signal is supplied to two mixers, to which the out-of-phase signals from the frequency generator are respectively supplied. The products of the two mixers are supplied to respective filters for filtering out ac components, and the respective amplitudes of the remaining dc voltage components of the respective mixed products are evaluated, the result of the evaluation indicating the presence or absence of the known frequency in the input signal.

REFERENCES:
patent: 2731566 (1956-01-01), Chalhoub
patent: 2911641 (1959-11-01), Kohler
patent: 2964622 (1960-12-01), Fire
patent: 2966584 (1960-12-01), Isley
patent: 3701012 (1972-10-01), Lang
patent: 4291269 (1981-09-01), Nossen
patent: 4318045 (1982-03-01), Krupa
patent: 4320531 (1982-03-01), Dimon
CCIR Recommendation 599, Report 795-1, "Directivity of Antennas for the Reception of Sound Broadcasting in Band 8 (VHF)", 1978-1982, pp. 205-213.

Affiliated with

Also associated with

Rating

Method and circuit for determining the presence or absence of at does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and circuit for determining the presence or absence of at, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and circuit for determining the presence or absence of at will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-706134