The band rejection filter circuit is not wide filter that can denial the frequency up to 60dB by we used the TL071 single chip op-amp it is very low distortion and work good at output to maximum to 100kHz or the range 1Hz to 20kHz
In the circuit we defined three resistors R1,R2,R3 are like value to 100K, and then two capacitors C1,C2 are equal to 330pF, For will reject the frequency at 50Hz.
By we can select the parts with the formula is F = 2×3.14xRC , And to get rejection well than 40dB if we should the resistor matched to 0.1% and capacitor to 1%.
The circuit is the right narrow filter for well audio system, we hope you enjoy with this circuit ideas.
This circuit provides for right half wave rectification of the input signal.
The op-amp IC no-NE5535 is Dual High Slew Rate Op-Amp, it is used for main of this circuit.
The input signal have two-phase supply are Fist, positive signals is the gain is 0; And second, negative signals is the gain is – 1.
By reverted both diodes no-1N4148, the polarity can be inverted. All resistor values are in ohms.
This circuit supply an accurate output signal, but the output impedance differs for the two input polarities and buffering be needed.
The output must slew through two diode drop when the input polarity reverses.
The NE5535 device will work up to 10kHz with less than 5% distortion.
When you are connected to buffer a tester to outside tool, we should have an booster with enough bandwidth and power disposition ability. This circuit is a very simple for unity gain buffer; it is only two pairs of emitter followers. The base emitter voltages of Q1 and Q2 cancel out, and so do those of Q3 and Q4. The preset is used to zero out any small dc offsets due to mismatching in the transistors.
It has reasonably high input impedance, 50 ohm output impedance, a wide bandwidth and high slew rate.
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