Intermediate electrician welding questions_555 oscillator_BT33F thyristor dimming circuit

The package has changed, so don't follow the 3D diagram exactly. Look at the 2D diagram.
 
The solder mask window means that the solder bridge should
be connected to the bus. Use a file to remove the copper.
The soldered universal board and PCB are a bit small. The changes (the directions of the 100pf ceramic capacitors are changed, one occupies 3 grids and the other occupies 2 grids) are the same. Ask the teacher which standard to use. There
 
is a copper sheet that needs to be cut off
and ground. After it is cut off, because there is no welding layer on the front, it can be seen through the back. The copper foil is scratched off and all the solder mask openings are flying wires between pins 2 and 6
 
of the tin bridge . Because there is no AC power supply, the video directly leads +9V and GND from the output of the 7809 to the 9V battery. The functions of each pin are as follows:  1 pin: ground.  Pin 2: Input terminal Trigger, this pin will determine whether the voltage is less than 1/3 Vcc.  Pin 3: Output terminal.  Pin 4: Clear terminal Reset. It should be connected to high level during normal operation.  Pin 5: Control voltage terminal. Generally not used, it should be connected to ground through a 0.01μF (103) ceramic capacitor to prevent the introduction of high-frequency interference.  Pin 6: Input Threshold, this pin will determine whether the voltage is greater than 2/3 Vcc.  Pin 7: Discharge terminal.  Pin 8: External power supply Vcc, range is 4.5V~16V, generally 5V is used. Working principle: Pin 8: Vcc is connected to high level. Pin 1: GND. Pin 4 is grounded: Reset (low level is active). For normal operation, pin 8 and Vcc are connected to high level together. Pin 5: Control voltage terminal is generally not used and should be grounded through a 0.01μF (103) ceramic capacitor to prevent the introduction of high-frequency interference. The relationship between the level of pin 3 of the output terminal and the input is as shown in the following table: Input Input Input Output Output 4 pin Reset 2 pin Trigger 6 pin Threshold 3 pin Output 7 pin Discharge Low - - Low Low High < 1/3 Vcc - High High Resistance high > 1/3 Vcc < 2/3 Vcc remains unchanged remains high > 1/3 Vcc > 2/3 Vcc Low After power on, capacitor C3 begins to charge. When V2 < 1/3 Vcc, output: pin 7 Discharge high impedance state, pin 3 Output high level LED does not light up when V2>1/3 Vcc, V6<2/3 Vcc, output: pin 7 Discharge remains (high impedance state), pin 3 Output remains (high level) When the LED does not light up, when V2>1/3 Vcc and V6>2/3 Vcc, the output: pin 7 Discharge is low level (capacitor discharge), and pin 3 Output is low level and the LED lights up V2>1/3 Vcc and V6<2/ When 3 Vcc, output: pin 7 Discharge keeps (low level) the capacitor continues to discharge, pin 3 Output keeps (high level) LED continues to light up. When V2<1/3 Vcc, output: pin 7 Discharge high impedance, pin 3 When the Output high level LED does not light up, this is a cycle. When the resistance of the potentiometer is large, the capacitor charges slowly and the LED goes off for a long time. When the resistance of the potentiometer is small, the capacitor charges quickly and the LED goes off for a short time because the potentiometer only controls the charging of the capacitor. Speed, that is, the time it takes for the potential of V2 and V6 to rise to 2/3 Vcc. When the potential of V2 and V6 rises to 2/3 Vcc, pin 7 immediately outputs a low level, and the capacitor discharges to pin 7 through R2. The resistance of R2 is fixed, so the capacitor discharge time is the same. The potentiometer only controls the time when the LED is off, and the time when the LED is on remains unchanged. Part of the content is taken from: Introduction to 555 timer - Zhihu (zhihu.com) If you want to know more about 555 timer, please refer to it yourself. Thanks for reading.