Free Circuit Diagram

This is a HI-FI tone control circuit with high Z input. This circuit is used to control HI-FI tone. Here is the circuit: To buffer op-amp operated feedback type tone control circuit, this circuit uses 2N3684 JFET. The 2N3684 JFET is implemented on this circuit because it has low noise characteristics and provides [...]

This is a video tutorial about RJ45. This video shows how to punch down an RJ45 keystone jack using a impact tool. The first thing that we gonna do is strip the wire. It is very important because when we connect the wire, it can cause the problem. And then, put the wire on RJ45, [...]

RJ45 is used to connect Ethernet port on your computer. There are two configuration: straight and cross. Straight RJ45 cables should be used to connect between computer and device such as switch or hub, and cross RJ45 cables should be used in computer-to-computer connection.  Some hub or switch has the capability to detect the cable [...]

I some cases, a differential input is needed for voltage measurement. Using the only one operational amplifier, you can build an adapter to provide a floating input for your ground-referenced  voltmeter. Use 1% tolerance metal film resistor for R1 and R2.  Adjust VR1 to give zero voltage output when the input probe is [...]

This is an ultra high input impedance AC unity gain amplifier circuit. This circuit is used to get unity gain from ultra high input impedance AC. Here is the circuit: Because we can’t reduce input capacitance of this circuit, so we use the 2N4416 which has low capacitance. It is operated as a [...]

This power factor controller accept voltage from 90 to 268 Vac,  that’s why we call it power factor controller with universal input, since any standards of mains supply  in almost any country would fall within that range. This power factor controller is capable of handling up to 450W load. Here is the schematic diagram of [...]