This is the circuit diagram of 35W Tube Power Amplifier with EL34. This tube amplifier designed in 1953 and worked from 1954 until 1989. If you’re interested with classic circuit and classic components, then you should […]
Circuit Schematic Diagram
Automatic 9V Battery Charger
This is the scheme diagram of automatic 9V battery charger circuit, the parts list provided below the schematic image. The circuit was designed by Jan Hamer, translated by Tony Van Roon dan republished in this circuit […]
Emergency Light + Alarm
This is the circuit diagram of emergency light included the alarm circuit to show you that there is no power source in your building due to shutted down or short circuit. When the electric in your […]
35W Power Audio Amplifier based LM391
Here the 35W power audio amplifier circuit based on LM391. Inductor L1 is constituted by 20 coils of wire, with thickness 0.9mm, round resistor R16. The transistors Q3-4 are the final amplification section, it should be […]
Multitone Siren Alarm
Here the simple schematic of multitone siren alarm circuit. This multitone siren is effective for reverse horns, burlgar alarms, and many others. It generates five various audio tones and is much more earcatching than a single-tone […]
Motion Filter Effect
This motion filter effect circuit will controls the initial frequency and controls how much the envelope follower responds to the input signal. An envelope follower/filter combination translates the typical dynamic properties of your axe into modulated […]
LED Pilot Light using FET
This is the LED pilot light (or LED indicator) circuit. LEDs (Light Emitting Diode) part are interesting things. They only operate at DC supply within specific tolerances, and generally connected with a current limiting resistor towards […]
A/B Box Switch 2 Inputs 1 Output with Dual Op-Amps
This is a A/B Box switch pedal schematic with two inputs and one output and featured with dual operational amplifier modules. This circuit was designed by Rick Barker. This A/B Box effect was originally designed for […]
2x90W Stereo Tube Power Amplifier with EL34
This document is the manual of 2x90W Stereo Tube Power Amplifier with EL34, model K4040 by Velleman. The document in PDF version contain of schematic diagram, part list, component guide, step by step how to build […]
Digital Fan Speed Control
This is the digital fan speed control circuit design that can be utilize to control the speed of 220V fans using induction motor. The speed control is nonlinear, i.e. in steps. The current step number is […]