In this tutorial, we are demonstrating a project crystal radio amplifier in detail. In general, a crystal radio receiver is known as a ‘Crystal set’. Explicitly, it is a basic radio receiver, famous since the beginning of the radio. Hence, it utilizes just the power of the radio signal to create sound, requiring no external power.
So, here is a crystal radio circuit with preamplifier and amplifier stages to improve getting sound. Hence, the circuit is easy to make and gives the astonishing best results.
Accordingly, the circuit is fabricated with the help of the LM358 IC. Although the IC behaves as a signal amplifier alongside a 2N3904 transistor. Moreover, the 0A91 diode identifies the input signal via an 80-turn inductor coil and then sends forward it to the IC via a transistor.
Hardware Components
The following components are required to make a Radio Receiver Circuit
| S.no | Components | Value | Qty |
|---|---|---|---|
| 1 | IC | LM386 | 1 |
| 2 | Transistor | 2N3904 | 1 |
| 3 | Antenna | – | 1 |
| 4 | Coil | 80 turns | 1 |
| 5 | Diode | OA91 | 1 |
| 6 | Variable Capacitor | 365pF | 1 |
| 7 | Capacitor | 100nF, 100µF, 220uF | 3, 1, 1 |
| 8 | Resistor | 100K, 10K | 1, 1 |
| 9 | Battery | 9V | 1 |
| 10 | Variable Resistor | 10k | 1 |
Lm386 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of LM386
Radio Reciever Circuit
Working Explanation
The circuit that appeared above utilizes a transistor 2N3904 as a preamplifier and an IC LM386 which amplifies the sound signals originating from the transistor to drive a smaller than-normal 8 ohms loudspeaker or earphones. Furthermore, this is a crystal radio speaker for enhancing the output sound to a crystal earphone or phone-receiving earphone. Hence, it utilizes a single transistor and is easy to make. Perhaps the best spot to add a transistor to a crystal radio is at the front end of an RF amplifier significantly. Additionally, the inductor coil has 80 turns which are well-balanced against the input voltage. You can likewise change the number of turns as per your design needs.
The circuit above is a basic but effective amplifier that will give astonishing execution improvement. Thus, the circuit is viewed as a regenerative receiver with an external identifier. Moreover, the sensitivity is high to such an extent that no cold-water pipe ground is required.
Applications and Uses
- The circuit is likewise utilized to enhance the output sound of crystal radio to a great extent.
- It can likewise help to enhance the faint radio signals of far and nearby radio stations.
