This decoder will respond to a preselected 4-digit DTMF number. IC7 is a Radio Shack IC device (part #276-1303..
In this proximity detector an NE567 tone decoder provides a signal of about 100 kHz that is fed to one sensor. The senso..
This circuit uses an RCA CA3162E (IC2) A/D converter. This converter has 12-bit output (BCD) which is sent to display decoder..
At the heart of the whistle swatch are a pair of tone detectors, each of which is built around an LM567 tone decoder, which are supported by a minimum of additional components. This whistle switch is designed to respond to only two or more occurrences of a specific tone, or sequence of tones, within a specified period to prevent false triggering. Depending on the relay used, various ac loads can be controlled. Microphone MICl picks up the sound and U2 amplifies the signal.....
The electromagnetic ring launcher is comprised of.four subcircuits: a clock circuit (built around U5, a 555 oscillator/timer configured for astable operation), a count-down/display circuit (built around U3), a 74190 synchronous up/down counter with BCD outputs that is configured for countdown operation; U4, a ECG8368 BCD-to-7-segment latch/decoder/display driver; and DISP1, a common-cathode seven-segment display), a trigger circuit (comprised of U6), an MOC3010.....
Apply a signal to each differential amplifier input pair. When the gate voltage is changed from one extreme to the ot..
A tone burst sent at the beginning of each transmission is decoded (at receiver) by a PLL causing output from pin 3..
Ul (a 4046 PLL containing a voltage controlled oscillator or VCO, two phase comparators, a source follower, and a Zener diode) is used to produce a low-frequency, pulsed output of about 40 Hz. The VCO's frequency range is determined by R6 and C2, which can be altered by varying the voltage at pin 9. The rising voltage causes the frequency to rise from zero to threshold and remain at that frequency as long as SI is closed. When SI is opened, Cl discharges slowly through Rl.....
The circuit is built around the LM567 tone decoder IC that requires about 100 millivolts at its operating frequency. The frequency is set by a 10 K variable resistor and can be between 700 and 1500 He..
This circuit, which was developed to monitor the traffic of bumblebees in and out of the hive, differentiates a-to-b motion from b-to-b motion. When used with an optical decoder, the circuit distinguishes clockwise from counterclockwise rotation and provides a resolution of one output pulse per quadrature cycle. Q1 and Q2 are mounted so that a moving object first blocks one phototransistor, then both, then the other. Depending on the direction in which the object is.....
Tones (from the DTMF) on the telephone line are detected by Ul. When a valid tone is received, pin 14 (D..
For the outband decoder shown here to work, the cable company must provide at least a 1 millivolt signal. Values for C1-C5 and L1-L4 ore found In Table 1. This circuit consists of an amplifier for the synch channel and a video detector which controls an attenuator so that the gain of the systems is increased dining synch intervals. ..
This encoder uses a single contact per key keyboard and provides all other switching function electronically. The diode between terminals 8 and 15 prevents the output going more than 1 volt negative with respect to the negative supply V-..
An NE567 tone decoder, tuned to the transceiver"s CW offset frequency, ensures that the transceiver will be tran..
This programmable gain circuit employs a CD4051 CMOS Analog Multiplexer as a two to four line decoder, ..
This circuit allows the effective power in a load to be controlled by varying the duty cycle of the on/off ratio of l..
This circuit shows the TP5700 directly interfacing to a low-voltage DTMF generator. VREGt supplies the necessary 2-V minimum bias to enable the TP5380 to sense key closures and pull its mute output high. VREGt then switches to a 3-V regulated output to sustain the tone dialer during tone generation. The TP5700 DTMF input incorporates the necessary load resistor to V-and provides gain, plus AGC action, to compensate for loop length. ..
The circuit shown here with RC filter (Figure T). Micropoco capacitor has a temperature coefficient of 125 10"6 60.10" 6'C" V In simplified circuits a fixed resistor (e g. 620k) can be used for a guaranteed switching level of < l6mV. ..
This twin-T oscillator produces six preset subaudible tones from 93 to 170 Hz..
ICl, an Intersil ICL 7106, contains an aid converter, a 3,1/2-digit LCD driver, a clock, a voltage reference, seven segment decoders, and display drivers. A similar part, the ICL7107, can be used to drive seven segment LEDs. The probe body is a five-inch length of light-weight aluminum tubing. The leads from the circuit are connected to the body and tip of the probe. The sensor functions as a variable resistor that varies Ql "s base current, hence its collector.....
Operational Amplifiers
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ANSI Standards
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