Rf-genie

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A variable oscillator operates in the frequency range of 3.2 to 22 MHz across two bands, enabling coverage from 80 meters to 15 meters, in addition to accommodating most crystal filter frequencies. Optional crystal oscillators at 455 kHz and 10.7 MHz can be activated for precise alignment. The generator's output is approximately 4 volts peak-to-peak when connected to a 500-ohm load. A simple voltage-divider attenuator is employed to manage the output level of the generator, while a secondary output supplies adequate drive for an external frequency counter.

The variable oscillator circuit is designed to provide flexibility in frequency selection, making it suitable for various applications, particularly in amateur radio and signal processing. The two-band operation allows users to select frequencies that are optimal for their specific needs, covering the HF amateur bands effectively. The inclusion of optional crystal oscillators at 455 kHz and 10.7 MHz enhances the precision of the oscillator, allowing for fine-tuning and accurate frequency alignment, which is crucial for applications requiring high stability.

The output stage of the oscillator is engineered to deliver a robust signal of approximately 4 volts peak-to-peak into a 500-ohm load, ensuring sufficient power for driving connected devices. The voltage-divider attenuator is a critical component that enables users to adjust the output level, providing versatility in interfacing with various equipment without risking damage from excessive signal levels. The additional output designed for an external frequency counter is an essential feature for users who require real-time frequency monitoring, allowing for seamless integration with measurement tools.

Overall, this variable oscillator circuit represents a well-designed solution for frequency generation, combining wide frequency coverage with precise control and adaptability for various electronic applications.A variable oscillator covers 3.2 to 22 MHz in two bands—providing coverage of 80 through 15 meters plus most crystal-filter frequencies. Optional 455 kHz and 10.7 MHz crystal oscillators can be switched on-line for precise if alignment. Generator output is on the order of 4 volts p-p into a 500 ohm load. A simple voltage-divider attenuator controls the generator's output level, and a second output provides sufficient drive for an external frequency counter. 🔗 External reference