An electromechanical actuator which creates an audible tone to indicate the presence of a high-voltage alternating current on a public switched telephone network (PSTN) line. The actuator consists of:
1. An electromagnet, intended to operate at 120 volts root-mean-square (RMS) AC voltage, consuming no more than 20 milliamperes of current;
2. A striker, made of iron or a chemically and physically similar metal;
3. A bell, made of a hard metal surface and shaped in such a way as to resonate when struck with a hard object.
When 120VAC appears on the PSTN telephone line, (1) alternately attracts and repels (2), causing (2) to strike (3) and produce an audible tone.
So everytime your phone rings, you owe me royalties....I haven't heard from you in a while, I think I'll give you a call tonight.
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An electromechanical actuator which creates an audible tone to indicate the presence of a high-voltage alternating current on a public switched telephone network (PSTN) line. The actuator consists of:
1. An electromagnet, intended to operate at 120 volts root-mean-square (RMS) AC voltage, consuming no more than 20 milliamperes of current;
2. A striker, made of iron or a chemically and physically similar metal;
3. A bell, made of a hard metal surface and shaped in such a way as to resonate when struck with a hard object.
When 120VAC appears on the PSTN telephone line, (1) alternately attracts and repels (2), causing (2) to strike (3) and produce an audible tone.
So everytime your phone rings, you owe me royalties....I haven't heard from you in a while, I think I'll give you a call tonight.