Power Inverter 60W 12V DC to 230V AC Using 2N3055

This is low cost fully transistorised power inverter 60W circuit capable of driving medium loads of the order of 40 to 60 watts using battery of 12V, 15 Ah or higher capacity. Transistors T1 and T2 (BC548) form a 50Hz multivibrator. For obtaining correct frequency, the values of resistors R3 and R4 may have to… Read More »

120W Power Amplifier + Power Supply

This is 120W power amplifier schematic using TO-3 package complementary transistors, NPN and PNP polarity. The well-known power transistor pair of 2N3055 and MJ2955 used in this circuit.  +/- 50V symmetrical (split/dual polarity) power supply with minimum 3A electric current should be used for maximum performance.

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 placed on heatsink. If are used the Q3-4 in packing TIPxxxx they can be placed straight above in PCB.… Read More »

Light Alarm with Timer 555

Here is the simple and low cost light alarm circuit built using timer IC 555 as the sound generator and a LDR to sense the environment light. This alarm is activated when the light beam on the LDR photocell is interrupted (You can use the light of a flashlight bulb which will make you a… Read More »

400W Power Amplifier “Safari”

This 400W power amplifier circuit often called as “safari” amplifier. The below circuit design is for single channel only, build two identical circuit for dual/stereo channels. The 400W power amplifier designed using two couples of power transistors that are TIP31 with TIP32 and 2N3055 with MJ2955. These types transistor are well known and widely used… Read More »

5W Simple Inverter

Here’s a very simple circuit inverter that converts DC current into AC current, from 12V DC to 220V AC with output power of 5W max. Inverter circuit is typically used for emergency lighting, since the power output is small, which is about 5W only. But you can use this inverter for other purposes that do… Read More »