Building an amplifier

Jayvin said:

I know, but for my project, i only need to compare the magnitude of the signal. If it can pick up 50Hz then kHz should not be a problem as i am not particularly interested in the signal itself but only its magnitude which would be varying according to my transmitter.

My goal is to capture the frequency, then compare its magnitudes. Is it increasing or decreasing? Thats it.

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Nulling out the 50Hz will be ineffective ---you need to peak the response at 10kHz
It has to be a Bandpass circuit,
HP won't work,as you will get interference from Medium Wave Broadcast stations.

Make a loop to pick up your 10kHz---this will give you a lot more signal to start out with.-----your WIFI antenna is not an antenna at these frequencies.
Even better,wind a coil on a ferrite rod,resonate it at 10kHz with a suitable capacitor in parallel.