Category: Electronics and Communication Projects

This small-size radio published is very interesting and useful for students. Using the circuit Smallest Radio Circuit Using Two Transistors described here, one can make a very compact MW radio receiver. This circuit uses only two transistors and a few passive components, as all the components can be easily placed in a small matchbox-size cabinet. Smallest Radio Circuit Using Two Transistors Coil L1 consists of 100 turns of 40 SWG insulated wire. Wind L2 over L1, which is 10 turns of the same wire. For L3, wind 56 SWG (approximately)…

Read More

A frequency oscillator is used to generate frequency oscillation, and a radio frequency oscillator is used to generate high-frequency which is known as a carrier wave. The circuit multiband CW transmitter is a continuous wave (CW) transmitter for transmitting morse code signal in a shortwave band. The circuit posted here is a variable frequency oscillator (VFO) whose frequency can be varied from 5.2 MHz to 15 MHz. The transmitted signal from this circuit can be received in a short wave band by any radio receiver. Circuit Description of Multiband CW…

Read More

Here is a circuit for a pocket radio using one IC LA4510 and three transistors. This circuit differs from ordinary circuits at the audio stage only. Here a small 9-pin IC LA4510 is used. It replaces three transistors, a driver transformer, and many other passive components. The amplifier circuit needs only one resistor! At zero signal level, this circuit draws 8-10 mA current only. With a 3-volt supply, this circuit can give 200 mW output power. For making this radio you may buy an ordinary pocket radio PCB and assemble…

Read More

Here is a  Frequency Multiplier circuit using PLL565.  Phase lock loop (PLL) has many diverse applications, among its applications PLL exhibits tremendous flexibility in frequency multiplication.  The IC 565 (IC1) can be used over the frequency range of 0.001 Hz to 500 kHz, and an operating voltage range of 6V to 12V. The frequency multiplier circuit  has a highly stable center frequency, selected by an external resistor (R1) and Capacitor (C1), which is given by The capture range of the feedback control system of the frequency multiplier circuit is decided…

Read More