This is the design diagram of 5 band graphic equaliser circuit build using operational amplifier chips, the NE5532 or LM833. The op-amp ICs is a good choice because of inexpensive and comes with fairly good quality output. Each IC contains dual op-amps circuit, so you will need 4 ICs of NE5532 or LM833 to build… Read More »
This is the very simple way to play a song with single 1.5 battery. You can build this circuit for gift acceccories. When the gift opened, then a song will be played.. It’s easy and cheap right..? 😀 . It just use a single small chip which will generate a song which already planted inside… Read More »
The following diagram is the FM transmitter circuit with FM transmision up to 4W. Voltage supply for this circuit is 12-16V with current consumption of 100-400mA. This circuit works with frequency of emission range of 88-108MHz. Transistor 2N2219 used as the main signal amplifier. 4 Watts FM Transmitter circuit design: Components List: R1, R2 =… Read More »
The following diagram is the 50W offline switching power supply circuit design. The circuit powered by a MOSFET. BUZ80A/IXTP4N8 for 220V AC voltage input and GE IRF823 for 110V AC input voltage. The output will be 5VDC with electric current up to 10A. The schematic diagram: Components list:
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 »
In the above circuit diagram, a CMOS operational amplifier (op-amp) controls the current via a P-Channel HEXFET power transistor (IRF9520) to maintain a constant voltage across R1. The current is given by: 1 = VREF/R1. The benefits of this configuration are:
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 cut phone line detector circuit is used to detect whether your phone line is active or not. Components List: R1,R2,R3 = 22M Ohms R4 = 2.2M Ohms C1 = 0.47uF/250V Mylar caps D1 = 1N914, NTE519, or other small signal diode Q1 = 2N3904, NTE123AP Q2 = 2N3906, NTE159 Q3 = IRF510, NTE2382, MosFet
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 »