Here the SW transmitter circuit based on IC BEL1895. This particular transmitter circuit works in shortwave HF band (6 MHz to 15 MHz), and can be applied for shortrange communication and for educational purposes. The circuit is composed of a mic amplifier circuit, a variable frequency oscillator, and modulation amplifier stages. Transistor T1 (BF195) is… Read More »
Here the simple Mini UPS circuit diagram. This circuit can provide an uninterrupted power supply (UPS) to operate 12V, 9V and 5V DC-powered instruments at up to 1A current. The backup battery will take up the load with no spikes or delay when the mains electrical power gets interrupted. It could possibly also be utilized… Read More »
This two chips AM radio receiver circuit is a tuned radio frequency (TRF) receiver of the standard AM (amplitude modulation) radio with broadcast frequencies at 550kHz-600kHz. This is a simple and easy to build AM radio circuit which only using two integrated circuits (IC). This circuit works with 9V voltage supply, you could use 9V… 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 »
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 diagram site. The circuit details are based on european standards: 120E, 150E, etc. The ‘E’ just stands for Ohms… Read More »
Below is the circuit diagram and PCB layout of FM wireless microphone: The range of frequencies for the FM broadcast band is 90MHz (MHz = Megahertz or 90 million cycles per second). Because the FM microphone has a variable tuned circuit, it can be tuned to a quiet spot on your local FM broadcast band… Read More »
Hobby power supply for electronic hobbysts. This is power supply circuit which have 2 output that are static output and adjustabled output. The static output is stabled and regulated output. The circuit is based around the 7805 voltage regulator. It has only 3 connections (input, output and ground) and it provides a fixed output. The… Read More »
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 try this circuit. The circuit is interesting but i think it is hard to find the tubes. Schematic Diagram: