Communications: electrical – Systems – Audible signals
Patent
1996-11-12
1999-04-13
Hofsass, Jeffery
Communications: electrical
Systems
Audible signals
3403847, 340513, 340539, 340553, G08B 300
Patent
active
058942629
ABSTRACT:
A doorbell circuit detects when one of a plurality of doorbell switches is depressed and provides an audible indication of the particular doorbell switch depressed. The doorbell circuit includes a detector circuit which will function properly with the diode, normally connected in parallel across one of the doorbell switches, connected with either polarity. A power supply is developed for the detector circuit from the doorbell transformer by way of the diode connected in parallel across one of the doorbell switches. The detector circuit includes one or more full-wave rectifiers, which provide a positive DC output signal irrespective of the polarity of the diode connected in parallel across the doorbell switch. Each of the doorbell switches is connected to an amplifier, which, in turn, is connected to a comparator. During conditions when none of the doorbell switches are depressed, the output level of the amplifier will be lower than the threshold level for the comparator to prevent an audible indication from being generated. Once one of the doorbell switches is depressed the amplifier will generate an output signal that is greater than the threshold value for the comparator to cause an audible indication to be generated.
REFERENCES:
patent: 3614760 (1971-10-01), Zimmet et al.
patent: 3711854 (1973-01-01), Reynolds et al.
patent: 4236147 (1980-11-01), Calvin
patent: 4523193 (1985-06-01), Levinson et al.
patent: 5260605 (1993-11-01), Barfield
patent: 5568122 (1996-10-01), Xydis
Bentley Roger Donn
McCavit Kim Irwin
Heath Company
Hofsass Jeffery
Tweel , Jr. John
LandOfFree
Electronic doorbell with reversible diode does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electronic doorbell with reversible diode, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic doorbell with reversible diode will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-224919