Here is the circuit diagram of battery tester designed by Matthew B.. This circuit can be used to measure the 1.5V and 9V battery. The circuit is very-very simple and very easy to built since it uses five resistors and a panel meter only, and of course it is inexpensive too. Components List: R1 =… Read More »
The following scheme diagram is the circuit diagram of simple easily tuned / adjustable sine and square wave oscillator. With this circuit you can easily generate sine/square wave which can be adjusted both the frequency and amplitude. The circuit uses IC LM101A, a general purpose operational amplifier (op-amp) and IC LM111, a high-speed voltage comparator… Read More »
The following diagram is the circuit diagram of 20W power amplifier which build based tube component EL34. EL34 is very famous tube and great for power tube amplifier. The circuit above is complete circuit contains tube amplifier circuit diagram and power supply circuit diagram. To make the stereo channel amplifier, build the similar amplifier circuit… Read More »
The following diagram is the schematic diagram of Ni-CAD battery charger circuit which featured with current and voltage limiting to keep the battery lifetime. The lamp L1 will be light brightly and the LED will be out when the battery is low and battery charging in progress, but the LED is very bright and the… Read More »
The following scheme diagram is the circuit diagram of VOX treble booster effect. A treble booster is an effects unit used by guitarists to boost volume and especially the high end of their tonal spectrum, and was popular mostly during the 1960s. VOX made a variety of boosters that were meant to be plugged directly… Read More »
The following schematic diagram is a small surround sound decoder circuit. You may use this decoder surround sound systems for your home audio system to make the audio system sound more “alive”. Parts List: R1-2-7-8-12-13-18-19-20=47Kohm R3-4-5-6-21-22-34-35=10Kohm R9-10-11-14-15-16-17=15Kohm R=23-24-25-33-36=100ohm R26-27-28-31-32=100Kohm R29-30=5.6Kohm C1-8=47uF 25V C2-7-9-14-23=47nF 100V C3-6=1uF 100V C4-5-10=33pF 100V C11-12-15=10uF 25V C13=82nF C16=18pF 100V C17=100pF mini… Read More »
The following circuit is tube distortion pedal for guitar effect. The circuit designed by Ron Black. Circuit Notes: IC1 : 747 dual op-amp, other ICs may be substitued but pinout will different. You should check the datasheet IC2 : LM340K-12V Voltage Regulator All resistors are 1/2 W Bridge Rectifier – Full wave bridge recitifier, 50… Read More »
The following scheme diagram is the circuit diagram of Lead-Acid battery charger. This circuit provides an initial voltage of 2.5 V per cell at 25 ℃ to quickly charge the battery. The charging current decreases as the battery is charging, and when the current drops to 180 mA, the charging circuit reduces the output voltage… Read More »
The following diagram is the schematic diagram of 12V NiCAD battery charger with charging rate of 200mA/Hour. Components List: Resistor: 1 K Ohm, 68 Ohm, 2 K Ohm, Potensiometer 10K Ohm Diode: IN4001, 2x Zener IN752 Transistor: 2N2219, 2N2222