Categories: AlarmFun Circuits

Musical Bell with Touch Switch

Here the circuit diagram of musical bell with touch switch and timer. This circuit is designed around CMOS IC CD4011 which work as the delay timer and IC UM66 which is well-known musical sound generator. When touch plates are bridged (touched) by hand for a moment, the circuit will start to produce music sound. Just after a short period (few seconds), the musical sound from this circuit will automatically stop.

The highest value of power source voltage for this particular circuit is +5 volts. The IC UM66 is unable to work over 3.3V voltage. IC 7805 regulator based power supply can certainly be applied to power this circuit.

Time delay can be adjusted by modifying the values of resistor R2 and capacitor C1. Three silicon diodes joined in series between pin 2 of UM66 IC and positive 5-volt rail maintain voltage carried out to pin 2 of UM66 less than 3.2 volts considering the decrease of about 1.8 volts across them.

Assemble the circuit and enclose into the plastic case. It suggested that the 5V regulated power supply also made and built in the case. Create some holes for switch, loudspeaker, mains power cable and port to the touch plate. Good luckā€¦

circuit diagram

Share
Published by
circuit diagram

Recent Posts

Guitar Synthesizer Schematic Diagram Collection

Guitar Synthesizer Schematic Diagram In this post, we provide a collection of schematic diagrams of…

54 years ago

Handy Talky HT DIY Schematic Diagram

Handy Talky Schematic Diagram This is an old electronic scheme of the Handy Talky (HT)…

54 years ago

Doorbell Ringer Birdie Tone

This is an old or "very old" schematic diagram of birdie tone or sound generator.…

54 years ago

200W MOSFET Amplifier based IRFP250N

Here is the 200W MOSFET amplifier powered based on four piece of IRFP250N, they are…

54 years ago

300W RMS Stereo Power Amplifier based IC TDA7294

This is the 300W RMS stereo power amplifier circuit project. This amplifier is based four…

54 years ago

Stereo Tone Control with Line In + Microphone Mixer

This is an active stereo tone control circuit using very well known op-amp IC of…

54 years ago