Here the project report of DC/AC pure sine wave inverter. This report focuses on DC to AC electrical power inverters, which aim to efficiently transform a DC power source to a high voltage AC supply, just like electrical power that would be presented at an electrical wall outlet. Inverters are utilised for a lot of… Read More »
The following diagram is the schematic diagram of 4 transistors FM transmitter circuit designed by Paul K. Sherby. Components List: R1,R2,R8 = 1K R3 = 100K R4 = 150K R5,R7 = 10K R6 = 220 ohm R9 = 10 ohm P1 = 5K trimpot D1 = 1N4002 Q1,Q2 = 2N3904 Q3,Q4 = 7001, NTE123AP C1… Read More »
This is a mini FM transmitter built and powered using 2 transistors, designed by Tony van Roon. This small transmitter is simple to build and its transmissions could be picked up on any common FM radio. It possesses a range of approximately 1/4-mile (400 meters) or even more, depending on the line-of-sight, obstructions by big… Read More »
The following diagram is the circuit diagram of voice transmitter which use FM signal carrier to transmit the vioce signal to the FM receiver device. Components List: R1 = 4.7K R2 = 330 ohm C1 = 0.001uF (1nF) C2 = 10-40pF C3 = 4.7pF Q1 = 2N3904 L1 = see text Misc = Electret mike,… Read More »
This is an easy FM tracking transmitter circuit project :). The scheme designed by Tony van Roon, and here the FM transmitter tracker diagram: Components List: R1 = 10K C1 = 100uF/10V C2 = 10nF C3 = 4-40pF trimmer capacitor C4 = 4.7pF IC1 = LM3909 Q1 = 2N3904 NPN transistor LED1 = Red LED/or… Read More »
Here is the USB sound card circuit based on PCM2706 which dedicated for USB audio. With USB controller module inside PCM2706, there is no more additional programming to the IC. The computer system will automatically detect this circuit when connected to the USB port. You will get stereo audio channel output from this circuit. Schematic… Read More »
This is the circuit diagram of a voice operated relay. It similar with sound activation switch circuit which will turn on and turn off (connect and disconnect) the switch depending on the sound input. The output switch of this circuit is act by a relay. Components list: R1, R7 : 1K R2, R4, R8 :… Read More »
This is a sound activated switch circuit. It’s will turn on and turn off based on a loud sound such as clapping your hands. You can adjust the sensitivity (how loud of a sound will activate the circuit) from a pin drop to a Mack Truck Horn. Very practical for a variety of projects. Add… Read More »
This is a very simple FM receiver which build based on one transistor only. No chip or another active component. The output is connected to earphones, you need an amplifier circuit if you want to listen the radio with a loudspeaker.