Soldering exercise Signal generator NE555 with adjustable frequency square wave signal

Simple kit for learning how to solder. The print on the board shows where the components should be placed.

The NE555 pulse frequency square wave signal kit has a frequency control and an on/off LED. It can be used for stepper motor pulses, testers, etc.

The functional principle
The multivibrator, which consists of the 555 timer, and the waveform diagram, as shown in the figure, are active after the power supply is turned on. The power supply VDD is used to charge the capacitor C via R1 and R2. When Uc < 1/3 VDD, the oscillator output is Vo = 1, and the discharge tube discharges.
After the Uc is charged to 2/3 or more VDD, the oscillator output Vo changes to 0, the discharge tube conducts, causing the discharge end (DIS) to be grounded, and the capacitor C is discharged via R2, causing the Uc to decrease.

When the Uc is reduced to one third or less of VDD, the oscillator output Vo changes to 1, the discharge tube conducts and at this moment the discharge end (DIS) is not grounded. The power supply VDD is recharged via R1 and R2 and the capacitor C is charged from one third of VDD to two thirds of VDD. Triggering and switching thus take place in a cycle in order to obtain a continuous variation on the output side Vo of the oscillation pulse shape.
The pulse width is 0.7 R2C TL material, determined by the discharge time of capacitor C; TH = 0.7 (R1 + R2) C, determined by the charge time of capacitor C. The pulse period T is TH + TL.

Overview:

• Main chip: NE555
• Input voltage: 5V-15VDC.
• Current 5V -> 15mA
• Current 12V -> 35mA
• Input current: >=100MA
• Input voltage: DC 5V-15V
• Output amplitude: 4.2 V V-PP to 11.4 V V-PP, depending on the input voltage
• Board size: 40.3mm x 36.2mm x 1.5mm

Output frequency range:

• LF file: 1 Hz - 50 Hz
• IF file: 50 Hz - 1 kHz
• High frequency file: 1 kHz - 10 kHz
• HF file: 10 kHz - 200 kHz

Scope of delivery:

• 1x soldering signal generator NE555 with adjustable frequency square wave signal
• 1x circuit diagram