NE555 Electronic Keyboard

Precautions for welding:
Speaker output: Weld the needle base first, then weld one end of the matching cable to the speaker, and insert the other end of the lead directly.
The battery box lead is directly soldered to the PCB, pay attention to the positive and negative electrodes.
Product Introduction
The way to play the keyboard is to use your fingers to press the keys corresponding to different notes, thus making a variety of beautiful sounds. This circuit consists of eight scales, which are controlled by eight buttons and can emit eight different notes.
Circuit characteristics
It has the characteristics of few components, simple circuit, low power consumption and easy production.
The PCB design layout is reasonable, concise and generous, the pads and traces are enlarged and thick, can withstand multiple welding, suitable for electronic teaching training, DNY competition, welding practice, etc.
How it works
This circuit is composed of the main chip NE555, resistors R1-R9, C1 and other peripheral components. The oscillation frequency is determined by the resistance of resistors R1-R8. The frequency selection is realized by tapping the keys of S1-S8. Operate the corresponding button to make the speaker emit eight different notes. If you press the button to operate the music, you can play beautiful music. Note: This product is powered by two 5th batteries (shipping does not include batteries)
Parameter
Product name: NE555 eight-note keyboard module
Working voltage: DC 3-12V
PCB specification: 116 * 21mm thickness 1.6mm