Free Circuit Diagram

This is a video of LED’s & Integrated Circuits Tutorial. This video shows how to make flashing box. to build a flashing box we need some tools and accessories, such as circuit board kit, UB5 size jiffy box, solder, soldering iron, and 9 DC battery. Before constructing the flashing box, we must plan about position [...]

Notch filter is known as band-cut filter or band-reject filter. The fuction of this filter is to remove some frequency portion of a signal. The schematic diagram of this filter circuit, a second order notch filter is depicted in the figure below. The formula is actually complicated, but by taking the R3=R4 and [...]

This circuit is line powered flasher, can be used in any application, and Christmas lamp is one of the example.  Look at the circuit’s schematic diagram below: The control for triggering the SCR is done by  Q1, Q2 and related resistors. The timing depends on R1,R2 & C1. To change flashing [...]

Using a single supply quad comparator LM339, LM239, LM2901, LM2901V, NCV2901, or MC3302, we can build a square-wave oscillator with simple circuit and formula. Here is the schematic diagram: This circuit is suitable if you need  many square-wave oscillators in one circuit, since the quad packaged comparator provide four comparators in one single  [...]

The excellent high input impedance, high slew rate, and high voltage qualities of CA3140 op-amp make it suitable for Wien-bridge sine wave oscillator. The basic circuit for Wien-bridge sine wave oscillator is shown in the figure below (the upper part). You can see the formula in the figure, when R1=R2=R, and C1=C2=C, then the formula [...]

You can use this circuit to give auto trigger for your secondary flash light. You don’t have to worry about wiring for the control, because using this circuit your secondary flash will be automati8cally triggered when it receive the light signal from the primary flash. Look at the circuit’s schematic diagram below. The [...]