Electronic Device for Measuring Reciprocal Time Intervals
A device is described which converts a train of electrical impulses into a succession of hyperbolic wave forms of amplitude proportional to the interval between successive impulses. These wave forms when applied to an oscilloscope furnish a display capable of showing rapid changes in the frequency of an electrical signal. Unlike conventional counting‐rate meters response to sudden changes in frequency is immediate so that averaging over several cycles is not required. The instrument as constructed operates in the lower audio‐frequency range and is being used in the study of the electrical discharge of single fibers of the optic nerve.
Remote control learning type with a circuit which is connected to a supply voltage, the circuit comprising: a) an infrared (IR) diode, said IR diode being sensitive to received light, and is capable of / voltages in response to the received light to generate photocurrents; b) a switch responsive to an associated drive signal, said switch selectively connects the IR diode with the supply voltage and separates therefrom, to provide an output IR signal in response to the drive signal; and c) an amplifier connected to said IR diode to photocurrents / voltages to supply in response to light which is directed to the IR diode, said IR diode only functions as a light receiver when the switch the IR diode switches off so that it does not respond to the drive signal.