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analogsystemsrf
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The UA741 does not have good -Rail Power Supply Rejection.

Use a different opamp.

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Notice location of the 25pF capacitor. The right end is the large-voltage-gain node for the opamp. The left end is two diode drops (Q16,Q17) above the negative rail.

At high frequencies (fast trash on the -VDD rail), the trash on the -rail is copied onto the VOUT (base of Q18) and then heavily buffered to the output pin.

analogsystemsrf
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