Field-strength-meter
The untuned, yet amplified Frequency Selective Measurement (FSM) circuit can detect signals ranging from 3 to 148 MHz and is remarkably resistant to overload, ensuring that the meter pointer does not reach its maximum. The core component of this circuit is a 324 quad operational amplifier, utilizing only one of its sections. It is designed to operate with a single-ended power supply, providing a minimum gain of 20 dB, with a self-limiting output current that prevents the pointer from being pinned.
The described circuit utilizes a 324 quad operational amplifier, which consists of four independent, high-gain, frequency-compensated op-amps. In this specific application, only one op-amp section is employed, simplifying the design while leveraging the amplifier's capabilities. The circuit is configured to operate in an untuned manner, allowing it to amplify a wide range of frequencies without the need for precise tuning components, which is advantageous in applications requiring broad frequency response.
The single-ended power supply design facilitates ease of integration into various systems, allowing for straightforward power connections and reducing the complexity of the power management. The minimum gain of 20 dB ensures that even weak signals can be amplified sufficiently for measurement purposes. Additionally, the self-limiting feature of the output current is critical in preventing damage to the measuring instrument or the circuit itself, as it avoids excessive current flow that could lead to saturation or failure.
In practical applications, this FSM circuit can be utilized in environments where signal detection at high frequencies is necessary, such as in communication systems, RF testing, or audio signal processing. The inherent overload immunity of the circuit enhances its reliability, making it suitable for use in dynamic signal environments where varying signal strengths may be encountered. Overall, this design presents a robust solution for frequency measurement and signal amplification across a wide bandwidth.The untuned, but amplified FSM can almost sense that mythical flea"s whisper-from 3 through 148 MHz no less-and yet, is so immune to overload that the meter pointer won"t pin. The key to the circuit is the amplifier, a 324 quad op amp, of which only one section is used. It"s designed for a single-ended power supply, will provide at least 20dB de gain, and the output current is self-limiting. The pointer can"t be pinned. 🔗 External reference
The described circuit utilizes a 324 quad operational amplifier, which consists of four independent, high-gain, frequency-compensated op-amps. In this specific application, only one op-amp section is employed, simplifying the design while leveraging the amplifier's capabilities. The circuit is configured to operate in an untuned manner, allowing it to amplify a wide range of frequencies without the need for precise tuning components, which is advantageous in applications requiring broad frequency response.
The single-ended power supply design facilitates ease of integration into various systems, allowing for straightforward power connections and reducing the complexity of the power management. The minimum gain of 20 dB ensures that even weak signals can be amplified sufficiently for measurement purposes. Additionally, the self-limiting feature of the output current is critical in preventing damage to the measuring instrument or the circuit itself, as it avoids excessive current flow that could lead to saturation or failure.
In practical applications, this FSM circuit can be utilized in environments where signal detection at high frequencies is necessary, such as in communication systems, RF testing, or audio signal processing. The inherent overload immunity of the circuit enhances its reliability, making it suitable for use in dynamic signal environments where varying signal strengths may be encountered. Overall, this design presents a robust solution for frequency measurement and signal amplification across a wide bandwidth.The untuned, but amplified FSM can almost sense that mythical flea"s whisper-from 3 through 148 MHz no less-and yet, is so immune to overload that the meter pointer won"t pin. The key to the circuit is the amplifier, a 324 quad op amp, of which only one section is used. It"s designed for a single-ended power supply, will provide at least 20dB de gain, and the output current is self-limiting. The pointer can"t be pinned. 🔗 External reference
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