Free Circuit Diagram

Bubba oscillator is another example of phase shift oscillator. The Bubba oscillator takes the advantage of quad op-amp package to get 45 degree phase shift for each section. The result is excellent d(phase)/d(t) to get very low frequency drift. Here is the schematic diagram of the circuit: Each RC section give 45 degree [...]

Metal Detector Circuit Topology One of the simplest method of metal detecting is by beat frequency oscillator. Basically, the circuit consist of two balanced oscillator. One oscillator provides the reference signal, and other oscillator is acting as the detector element. The reference oscillator’s frequency is fix, while the detector oscillator is variable depending on [...]

This is a Colpitts-crystal oscillator circuit. It is suitable for low frequency crystal oscillator circuits. Using the 2N3823 JFET, this circuit has excellent stability because the temperature will not vary the 2N3823 JFET circuit loading. Here is the circuit : [Source: National Semiconductor Application Note]

Op-amps has been widely used in low frequency oscillator (frequency <= 100kHz), but we can actually use it for high frequency crystal oscillator as long as we have an op-amp with the proper bandwidth. An excellent gain stages can be implemented using LT1190 and LT1191 op-amps. Here is the schematic diagram of the circuit: [...]

Crossover Calculator An online crossover calculator in this link is not only capable of designing 1st order crossover, but 2nd, 3rd, and 4th crossover calculation is also supported. Designing a 3 way crossover using the tool is very easy, you just need to fill the form to specify the design parameters: tweeter impedance, midrange [...]

This video is tutorial how to use oscilloscope. This video shows how to use the oscilloscope. The first thing to do is prepare the probe, the simulator generator and the simple circuit. And then turn on the oscilloscope and calibrate the oscilloscope. From the oscilloscope we can obtain some information, such as the voltage of [...]