Back to results
US 3,953,806 AGranted
Displaying amplifier output amplitude
AssigneeBose Corporation
InventorJoseph L. Veranth
Life of this patent
Estimating the term…
Abstract
A sequence of light emitting diodes are progressively illuminated with progressively increasing instantaneous amplifier output signal amplitude with the last pair of light emitting diodes illuminated simultaneously to indicate amplifier clipping.
Claims5
Apparatus for indicating the instantaneous amplitude range in which an output signal amplitude resides comprising,
- a plurality of light emitting diodes,
- a corresponding plurality of transistors in series with respective ones of said light emitting diodes,
- an input line for receiving a signal whose level is to be monitored,
- means for coupling the base of each transistor to said input line to progressively render conductive more of said transistors with increasing signal level amplitude on said input line,
- a power amplifier having its output connected to said input line and having a source of d-c potential of magnitude greater than the maximum amplitude on its output terminal except when clipping occurs,
- and means for biasing one of said transistor bases with said d-c potential so that the associated light emitting diode conducts only when the potential on the power amplifier output exceeds a predetermined fraction of said d-c potential.
3 more elements
Apparatus for indicating the instantaneous amplitude range in which an output signal amplitude resides comprising,
- a plurality of light emitting diodes,
- a corresponding plurality of transistors in series with respective ones of said light emitting diodes,
- an input line for receiving a signal whose level is to be monitored,
- means for coupling the base of each transistor to said input line to progressively render conductive more of said transistors with increasing signal level amplitude on said input line,
- a common terminal and a plurality of attenuating means connected between said input line and said common terminal with each attenuating means coupled to a respective one of said transistors with consecutive ones of said attenuating means coupling the signal on said input line to an associated one of said transistors with progressively greater attenuation so that the number of illuminated light emitting diodes is representative of said instantaneous signal level,
- wherein said attenuating means comprise means for establishing said progressively greater attenuation as a logarithmic function of the signal on said input line so that the difference between successive amplitudes just large enough to ignite adjacent light emitting diodes corresponds to substantially the same predetermined decibel difference.
3 more elements
Dependencies are inferred from the claim text.