Frequency selective annunciator system

Details Frequency selective annunciator system Frequency selective annunciator system

1978-06-07

1980-12-16

Swann, III, Glen R.

Communications: electrical

Condition responsive indicating system

With particular system function

340533, 340658, G08B 2500

Patent

active

042400783

ABSTRACT:
The supervised conductive loop comprises a plurality of switch elements connected in series with a DC current source. Encoder modules are located in parallel with each of the switch elements. The encoder module comprises an oscillator and an impedance element. When a switch element is opened, the oscillator associated with that switch is energized and places an AC signal on the loop. The frequency of each oscillator uniquely identifies the associated switch element. The impedance element, formed by a resistor and a capacitor, is used both as a filter for the power supply voltage to the oscillator as well as a bandpass filter to permit oscillator signals present on the loop to bypass open switch elements and be detected at any location in the loop. Frequency identifying means are coupled to the loop to permit an indication of which oscillators have been operated.

REFERENCES:
patent: 3626316 (1971-12-01), Connell, Jr.
patent: 3710372 (1973-01-01), Andersson et al.
patent: 3760359 (1973-09-01), McQuown, Jr.

Affiliated with

Also associated with

Rating

Frequency selective annunciator system does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Frequency selective annunciator system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Frequency selective annunciator system will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-610667