Description
Description:Product parameters:
Product Name: Laser Electronic Harp
Supply voltage: DC voltage 5V
Board size: 91*63mm
Finished product size: 91*63*55mm
Finished product weight: about 200g
Product description:
The laser harp is a harp without strings. Instead, it is replaced by a bright beam. Users only need to pluck the light beam, as if plucking the strings, they can still play a melody, and they also have built-in music for playback and listening. The circuit consists of two parts: photoresistor and STC89C52.
When the light beam emitted by the laser tube is blocked, the corresponding photoresistor senses and produces resistance changes. A system composed of 7 photoresistors produces high and low potential changes, and the single-chip microcomputer reads the high and low potential changes of the photoresistor to complete the input of operating instructions. The single-chip microcomputer controls the data to transmit data through the serial port according to the instruction information, and assigns values to the data port connected to the speaker and the water lamp to make it react accordingly. When there is laser irradiation, the microcontroller reads the voltage of the photoresistor, and it is at low level at this time. When there is no laser irradiation, the single-chip microcomputer reads the voltage of the photoresistor, then it is high at this time. In this way, when the light of the laser is blocked, a switch effect can be produced in the circuit. The human ear can hear the sound frequency from 20Hz to 20kHz, and the harp note frequency should also be in this range.
However, different notes have their own fixed frequency. The above-mentioned audio can be generated through the 16-bit timer of the 52 single-chip microcomputer. For example, the standard tone la of the harp is 440 Hz. Through calculation, it can be known that its half cycle is 1136us.
In this way, as long as the pin level is changed during the half cycle, a 440Hz square wave can be generated. Then through the electro-acoustic conversion element (horn), the standard sound a can be produced, and other notes are also produced in this way.
Features:
1. There are 7 strings in total, and the buzzer emits the corresponding sound level when the strings are cut
2. When the string is cut, the LED corresponding to the string lights up, a total of 7 LEDs
3. You can switch between three tones of mid-high, low, and tone by pressing KEY2
4. Play the stored four songs by pressing KEY1
(Little star, a bird fell into the water, happy birthday, only mother in the world is good)
Package Included:
1 x DIY Laser Harp Electronic Welding Kit
