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I'm experimenting with op-amps and ceramic filters at 455 kHz. I chose TL071 because it was readily available and the datasheet specified a slew rate of 13 V/μs and a GBW of 3 MHz. But in the datasheet it shows that the large signal differential gain drops dramatically after 100 Hz.

My Ltspice simulation also shows similar effect.

My question is can I use this device for making a 455 kHz signal amplifier in practice as the simulation shows about 18 dB gain at 400 kHz?

Transistor
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User
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    Compare with *a single transistor* amplifier, which has more potential gain at your frequency-of-interest. – glen_geek Oct 18 '20 at 13:38
  • Yes of course I'm aware of that, I was only investigating on the possibilities out of curiosity. – User Oct 18 '20 at 15:51

1 Answers1

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My question is can I use this device for making a 455 kHz signal amplifier in practice as the simulation shows about 18dB gain at 400KHz?

The 18 dB of gain you get roughly tallies with the open loop response from the data sheet so, you can amplify the 455 kHz signal but if you are expecting a clean distortion free output it might not be quite like that because the op-amp is running pretty close to to its top-end of the spectrum and op-amps rely on a lot of "spare" open-loop gain for a "high fidelity" signal amplification.

Andy aka
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  • Thank you. Could you recommend another device which could be used if I wanted a clean signal while not being an overkill for the purpose? – User Oct 18 '20 at 08:32
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    Not really a recommendation but choose an op-amp with a higher gain-bandwidth product if you want decent reliable amplification and fidelity. You can find plenty that are 10 MHz GBP and still quite a few that are in excess of 100 MHZ GBP. – Andy aka Oct 18 '20 at 08:33
  • BTW this is not a technical question but I don't know a platform where I could ask you, I'll delete this after you answer it. Your songs are nice, which DAW do you use? – User Oct 18 '20 at 08:38
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    I use Cubase (an old version) and master in wavelab. I'm a steinberg guy through and through. Thanks for asking. – Andy aka Oct 18 '20 at 08:47
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    @ASWINVENU are you a musician? There's always facebook/messenger if you are into the crap that comes with it. [How about this question](https://electronics.stackexchange.com/questions/520724/amplitude-stabilisation-of-lc-oscillators) - I don't know if my reminders are getting through. Maybe not? – Andy aka Oct 18 '20 at 08:56