simple rc circuit

The diagram illustrates a straightforward and efficient receiver designed for activating garage doors, starter motors, alarms, warning systems, and various other applications. The silicon-controlled rectifier (SCR) utilized in this circuit features an exceptionally low trigger current of 30 µA, requiring only 30 µW of input power to activate the relay. This circuit operates as a tuned radio frequency (TRF) receiver, specifically for standard AM (amplitude modulation) radio frequencies ranging from 550 kHz to 600 kHz. It represents a simple and easy-to-construct AM radio circuit that employs two integrated circuits (ICs) and operates on a 9V power supply, which can be provided by a standard 9V battery. The circuit diagram depicts a mini AM radio receiver. Any general-purpose transistors can be utilized in this circuit, with BC549 transistors being a suitable option. The design incorporates a compact three-transistor regenerative receiver with fixed feedback, resembling the functionality of the now-obsolete ZN414 radio IC. Additionally, the circuit includes a simple mixer featuring four inputs and two operational amplifiers (op-amps), which is appropriate for mixing microphone signals or effects outputs. The overall gain from input to output is unity when the associated potentiometer is fully turned up, although the gain can be adjusted to ten or any other reasonable value. Furthermore, there is a straightforward metal detector circuit based on a CS209A IC, which yields impressive results while drawing minimal current from a 9V battery. While it performed well on the bench, its effectiveness outdoors for typical metal detecting may be limited. Nonetheless, it serves as an excellent circuit for sensing applications. Lastly, a basic inverter circuit is presented that converts 12V DC into 220V AC, providing an output power of 5W. This inverter circuit is typically employed for emergency lighting due to its limited power output, but it can also be utilized for other low-power applications.

The circuit described integrates several essential components that facilitate its functionality across multiple applications. The receiver section employs a tuned circuit that enhances signal selectivity, allowing it to effectively pick up AM radio signals within the specified frequency range. The use of a low-power SCR ensures that the relay activation occurs with minimal energy consumption, making the circuit efficient for battery-operated devices.

The regenerative receiver design, characterized by its fixed feedback mechanism, increases sensitivity to incoming signals, thereby improving reception quality. The inclusion of the BC549 transistors allows for reliable amplification and signal processing within the circuit. The operational amplifiers in the mixer section are configured to combine audio signals from different sources, enabling versatile audio applications such as mixing for live performances or sound effects.

In the metal detector configuration, the CS209A IC serves as the core component, leveraging its capabilities to detect variations in electromagnetic fields caused by metallic objects. While the circuit may have limitations in outdoor environments, it remains a practical choice for hobbyists and educational purposes.

The inverter circuit's ability to convert DC to AC power is particularly useful in scenarios where AC power is required but only DC sources are available. The compact design and low output power make it suitable for small devices and emergency lighting solutions, ensuring versatility in its application.

Overall, this collection of circuits exemplifies the integration of simple components to create functional electronic devices, showcasing the principles of radio frequency reception, audio mixing, metal detection, and power conversion.Above diagram is a very easy and efficient receiver for actuating garage doors, starter motors, alarms, warning systems and many some other possibilities. The SCR, which has a extremely low trigger current of 30 uA is typical - it demands an input electricity of just 30 uW to activate the relay.

A high Q tuned. This circuit is a tuned radio freq uency (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 standard battery to cupply this. This is the circuit diagram of mini AM Radio receiver. All general purpose transistors should work in this circuit, you can use BC549 transistors for this circuit.

The circuit use a compact three transistor, regenerative receiver with fixed feedback. It is similar in principle to the ZN414 radio IC which is now replaced by the. Here the simple mixer with 4 input and 2 op-amps: A basic mixer suitable for mixing microphones or even effects outputs. The overall gain from input to output is one if the pot related towards the input is full up. You can make this a net gain of ten (or any other reasonable gain) by. This is a very simple and easy build metal detector circuit, built based on a CS209A IC. The circuit will give surprising results and draws extremely small current from a 9 volt battery. It worked great on the Bench, But not so good outside for common metal detecting. But Definately a great circuit for sensing. Here`s a very simple circuit inverter that converts DC current into AC current, from 12V DC to 220V AC with output power of 5W.

Inverter circuit is typically used for emergency lighting, since the power output is small, which is about 5W only. But you can use this inverter for other purposes that do not. 🔗 External reference