Professional strobe lights are difficult and expensive. But for conducting home experiments, they are not required. For them, a simple device is enough, which can be made from just a few common parts.
Instructions
Step 1
Take your broken cell phone charger. Wait a few hours after the last disconnection from the mains so that the input filter capacitor in it is discharged. Remove the board from it.
Step 2
Take two resistors with a nominal value of 300 kilo-ohms and a power of 2 watts. Connect a regular two-wire power cable to the pins of the plug built into the body of the charger, connecting such a resistor to the break of each of its wires. Insulate all connections carefully. Place the resistors inside the charger case.
Step 3
Carefully saw off the section where the diode bridge is assembled from the board removed from the charger. Be sure to make sure you didn't cut out any other parts with it, especially electrolytic capacitors. Connect the power cord to the bridge pins for AC voltage input.
Step 4
Take a variable resistor with a resistance of about two megohms. Place it with the axis towards you and the leads down. Connect one of the contacts of the rectifier bridge, designed to remove the rectified DC voltage, simultaneously to the left and middle terminals of the variable resistor. Connect the right terminal of the same resistor to the other output contact of the rectifier bridge through a capacitor with a capacity of 0.05 microfarads, designed for a voltage of at least 630 volts.
Step 5
In parallel with the capacitor, solder any miniature neon lamp, for example, INS-1, TN-0, 2, TN-0, 3, or Chinese NE-2.
Step 6
Install the stroboscope into the plastic housing. Make a hole in it for the light from the neon lamp to exit. On the axis of the variable resistor, be sure to put on a wide handle made of insulating material, excluding touching any of its metal parts.
Step 7
Connect the device to the mains, then, by turning the knob, adjust the flashing frequency of the neon lamp. In cases where its blinking frequency exceeds 50 Hz, it will be modulated by this frequency. This is a disadvantage of such a stroboscope, but it makes it possible to exclude the use of an electrolytic filter capacitor in it.
