Audio To Uhf Preamp Circuit

The Signetics NE5204 or NE5205 can be utilized in this audio frequency to 350-MHz (-30 dB) preamplifier. For a requirement of 600 MHz at 3 dB, the NE5205 should be employed. The noise figure is 4.8 dB at 75 MHz and 6 dB at 50 MHz. Additionally, the gain is approximately +20 dB across the passband.

The NE5204 and NE5205 are high-frequency, low-noise amplifiers designed for applications requiring amplification of weak signals while maintaining a low noise figure. The NE5204 is suitable for frequencies up to 350 MHz, making it ideal for various audio frequency applications, while the NE5205 extends the operational bandwidth to 600 MHz, providing enhanced performance for more demanding RF applications.

In terms of circuit design, the preamplifier configuration typically includes input and output matching networks to optimize performance over the specified frequency range. The input stage may consist of a resistor-capacitor (RC) network to filter unwanted high-frequency signals while allowing the desired frequency components to pass. The gain of approximately +20 dB indicates that the amplifier is capable of significantly boosting the input signal, making it suitable for applications where signal integrity and strength are critical.

The choice of the NE5205 for applications requiring a 600 MHz bandwidth is essential due to its lower noise figure at higher frequencies, ensuring that the amplified output retains clarity and fidelity. The noise figures of 4.8 dB at 75 MHz and 6 dB at 50 MHz are indicative of the amplifier's performance, with lower values representing better signal-to-noise ratios, which is crucial in high-frequency applications.

Overall, the NE5204 and NE5205 amplifiers are versatile components in RF and audio frequency applications, providing reliable performance with a focus on low noise and high gain. Proper circuit layout and component selection will further enhance the performance of these devices in practical applications. The Signetics NE5204 or NE5205 can be used in this AF to 350-MHz (-30 dB) preamp. If 600 MHz @ 3 dB is needed, use the NE5205. The noise figure is 4.8 dB at 75, 6 dB at 50 . Gain is approximately +20 dB over the passband.