Electrical audio signal processing systems and devices – Including amplitude or volume control
Patent
1987-11-23
1989-01-10
Ng, Jin F.
Electrical audio signal processing systems and devices
Including amplitude or volume control
381101, 381109, 84 127, 330279, H04N 704, G01H 146, G08B 300
Patent
active
047979321
ABSTRACT:
Apparatus and method for establishing and changing the volume level of a tone generator which may be used in connection with auditory feedback in a point of sale terminal or other business machine include a microprocessor having a timer with two settable registers which can be set to establish the duty cycle of a signal, an inverting buffer coupled to the timer output, an integrating circuit to which the signal from the buffer is applied, a transistor driver for a speaker to which the integrated signal is applied, and the speaker, the volume of the tone of which may be changed by altering the relative counts of the two timer registers.
REFERENCES:
patent: 3386046 (1968-05-01), Myer
patent: 3541548 (1970-11-01), Cogar et al.
patent: 3711783 (1973-01-01), Kelling
patent: 3961281 (1976-06-01), Wooling, Jr.
patent: 4151481 (1979-04-01), Funston et al.
patent: 4348932 (1982-09-01), Kashio
patent: 4416178 (1983-11-01), Ishida
patent: 4435679 (1984-03-01), Bedard et al.
patent: 4449104 (1984-05-01), Agnor et al.
patent: 4482888 (1984-11-01), Todaka et al.
patent: 4506579 (1985-03-01), Rossum
patent: 4677890 (1987-07-01), Yannes
patent: 4694725 (1987-09-01), Seevers et al.
Patents Abstracts of Japan, vol. 8, No. 269 (P-319) (1706), 12-8-84; JP 59-136846.
Patents Abstracts of Japan, vol. 9, No. 23 (E-293) (1746), 1-30-85; JP 59-169213.
Keys John B.
Rohulich John J.
Hawk Jr. Wilbert
Kim David H.
NCR Corporation
Ng Jin F.
Sessler Jr. Albert L.
LandOfFree
Speaker volume control apparatus and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Speaker volume control apparatus and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Speaker volume control apparatus and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2112905