I can put a tuner and a demodulator into it. but in the simulator it gives me higher output when I changed values, anyway I want to know can it works correctly or not?
You are trying to demodulate a signal supposedly in the megahertz range with an operational amplifier designed to operate on the audio frequency.
I think it can work at higher frequencies, What can I use instead of it?
Your belief is based on what technical basis? At least the operational amplifier datasheet clearly show it start decreasing its open loop gain well below the megahertz range. Moreover, as Brian already mentioned and repeated above, it is missing fundamental circuits of standard receivers in your scheme. And to complete, you did not even mention what kind of demodulation, or what frequency band you want to work with.
Reviewing the apparent source of information http://www.techlib.com/electronics/allband.htm reveals confusion already in some of the original circuit schematics, but you get a least a glimpse of what they try to achieve.
The final paragraph is describing the hand sketched schematic copied in post #3. It raises serious doubts that the author of this compilations actually understands demodulation principle.
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I like to suggest a different approach: Specify the purpose of your design, e.g. which wireless signals you want to detect.
My comment is about the techlib author.
In my view, none of the circuits works "well", some not at all. Problem is however the lack of specification, which signals do you want to detect respectively demodulate?
How can I correct them?
A radio frequency receiver is comprised of several circuits, each one doing its own task:
https://en.wikipedia.org/wiki/Radio_receiver_design
For each one you have to calculate component values according to specification you want to achieve. Your circuit barely seems to have all parts as shown at the above link, therefore rather than corret your circuit, you should redesign instead of copy-paste circuit from somewhere without knowing exactly what they do.
I want to simply receive them without tuning and demodulating
1.
It is possible to receive magnetic or electromagnetic transmissions in the audio range, and listen to them without demodulating. You only need to amplify what comes from the antenna. (The antenna needs to be large.) Noises originate from atmospheric phenomena, lightning, whistlers, etc.
2.
Ambient mains hum emanates from house wiring and appliances. If you figure out a way to create a good wireless coupling to it, then you might have a source of energy harvesting.
3.
Your radio AM band probably has one or two strong local stations. Anyone can build an old-fashioned 'crystal' radio receiver, which needs no power. A homemade tuning coil and capacitor tends to have low selectivity, so you might hear two or more stations simultaneously.
Man it's an All Band Receiver not a simple crystal radio!
Aside from the controversial blog mentioned above, I did not find anywhere an amazing "all-band" receiver. Actually, there are ICs which do that, but these have standard AM/FM receivers built in, so there are a clear misuse in the terminology from your side, diverging from the conventional.
The closest of an "all-band" receiver which we could recognize is what was formerly known as a galena crystal receiver, which in other words had no intermediate frequency, but even this circuit does not look like the one that you insist that works, therefore I recommend you claim the patent of the above discovery, but first you should prove that it works, at least in simulation.
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