Beeper - Buzzer

Bell circuit with two 555 timers

This simple Bell circuit uses two 555 timers. The frequency is controlled by the capacitors that must be preserved almost identical in value to each other for best results. Fine tuning is done with R1 and R2. ..

Chime Circuit with 4049

Resistor R1, capacitor C1, and two converters form a square wave generator, which produces the basic tone. The generator is sui followed by an inverter which serves as both a buffer and a driver for the President. The resistor R2, which has a minimum value of 100 ohms, limits the power and volume controls. The diode D1, capacitor C2, resistors R3 and R4, and two in converters to create the pulse generator which determines the power-up and decay times of the ring. ..

Water Detector with Buzzer

This is a simple circuit that can be used as a detector for water, such as a bath full detector. The terminals 'sensor' is connected to the probe. This may consist of two electrodes, or a PCB with surface adjacent tracks, the odd jobs with one socket, and the same with the other. If there is a noticeable drop, there is a running stream, so T1 and T2 are conducting. Bz1 gives a signal. The circuit must be powered for safety with a 9V battery, not with a power supply. The circuit can also be used for leaking washing machines...

Wireless Bug detector

This fairly simple circuit makes it possible to place such a wall as a conduit to locate. It is a conduit for power, no water or gas-seeker. The only requirement is that there is tension on the line. The antenna in the table can consist of a simple piece of copper wire. The correct adjustment is done through R7, in order to prevent the buzzer and LEDs still light up even though there is no leadership in the area. ..

Simple Buzzer driver with 555

This very simple circuit just uses a couple of resistors, a capacitor and the easily available 555 timer IC. The 555 is setup as an astable multivibrator operating at a frequency of about 1kHz that produces a shrill noise when switched on. The frequency can be changed by varying the 10K resistor...

Beeper driver with 555

This circuit produces the sound of a beeper like the one in pagers which produces a "beep-beep" sound. Basically the circuit consists of a 555 timer oscillator which is turned ON and OFF periodically. The first IC(left) oscillates at about 1Hz. The second IC is turned ON and OFF by the first IC. The first IC determines how fast the second IC is turned ON/OFF and second IC determines the tone of the final output. By varying the VR1, the changeover rate can be adjusted. By varying VR2 the tone can be adjusted...

Oscillators for Buzzers and telephone Earpieces

In order to generate a single note you may try these simple circuits. With only three components you may implement some basic buzzers. You need a telephone earpiece for the first circuit. Any old telephone set has got one of those magnetic earpiece that is right for our purposes. Add an extra capacitor and a transistor and you have your buzzer. Frequency of operation is about 1800 Hz and the capacitor must be changed if you wish to have a different frequency. The second circuit is implemented with a ceramic sounder: its intrinsic capacity is used to make another simple buzzer. Working frequency is 800 Hz and power drain is really low. ..

Piezo Buzzer driver

This is a basic Buzzer driver circuit with resonance frequncy approximatly 5 Khz, 85 dBA. It operates on 3 to 28 v DC at 6mA...

Acoustic Tone indicator

With this circuit, we can have a acoustic clue, frequency 2KHZ, when we have a short vibration in his entry. It is constituted from monostable multivibritor (with schmitt trigger inputs), with duration roughly 100msec, oscillator TTL, that oscillating in their 2KHZ and one rung of expense a loudspeaker or piezoelectric element. The square vibration that is applied in his entry, trigger his multivibritor that with line drive the oscillator and his the loudspeaker. With switch S1, we can select the polarity of vibration of entry, if this is positive or negative. The frequency of oscillator can change, if we change the capacitor C4 or resistance R2, so that changes also the frequency of sound that we hear from the loudspeaker and with the TR1 we alter the intensity of him tone in the loudspeaker. ..

Timer Circuit with optocoupler

A small circuit that can find a lot applications of measurement time. She has the possibility us inform with sound signal from the BZ1. At the same time, exist the possibility drive a external circuit via the optocoupler IC2, after we connect the applicable circuit in contacts [ A ] and [ B ]. The circuit is based on IC1 (4060), which include in his inside, oscillator and a binary divider of 14 stage. The frequency operation of oscillator is determined by a circuit R-C that connected in pins 9,10,11 of IC1. We give supply in the circuit, with switch S1, is presented a pulse in 12 [ RESET ] via C1 and R3, null him counter, require the measurement of pulses to begin from the zero. ..

Limit Temperature Buzzer

The circuit is small regulatorof temperature, us warns for the increase of temperature. The control of temperature becomes from the thermistor TH1, that is negative factor. His resistance is altered between in the 10K in temperature 25° C and roughly in the 1K in their 94° C. The trimmer TR1 regulates the precise temperature in which the Q1-2, connected as darlington, conduct, making him relay K1 close also the buzzer BZ, sound. The alarm is activated when the temperature becomes bigger than predetermining. The thermistor it should he is placed far from the remainder circuit, in order that this is not in danger from the temperature...

Tone generator with 555

This circuit is based around the 555 timer circuit, used as an astable (free running) oscillator. The frequency (pitch) of the tone is set by the resistors and capacitors in the left side of the circuit. The first one is a potentiometer (variable resistor), this is our pitch control, which is basically all the external components you need. The capacitor to the far left is to reduce as much noise or undesired operation of the potentiometer, getting a smooth pitch change when adjusting...

Water limit buzzer

Water Level Buzzer is a simple circuit which will buzz when water reaches the sensor level. Input - 9 VDC @ 40 mA. Output at Buzzer. Terminal pins for supply voltage. Power-On LED indicator. Four mounting holes of 3.2 mm each. PCB dimensions 32 mm x 35 mm..

This box is a portable transfer standard to maintain and carry with you a local time signal of 59 short beeps (pips) plus a long 0.4 sec beeeeep on the full minute. At the start of the job, the box is started by manually synchronising it by ear with a reputable time signal (GPS, WWV/H, or Telstra 1194 on a fixed landline telephone). The box then keeps bleeping, can be taken to an observation site, and can be used there for an hour or so, before the time slowly drifts too far out of calibration...

Inverters U1a and U1b are connected in a simple RC oscillator circuit. The frequency is determined by the values of R1, C1 C2 and the internal characteristics of the integrated circuit. As long as the circuit is oscillating, a positive dc voltage is developed at the output of the voltage-couple circuit: C3, D2 and C4. The dc voltage is applied to the input of U1c-the third inverter amplifier-keeping its output in a low state, which keeps Q1 turned off so that no sound is produced by BZ1...