Sorry i didnot mention the unit of the resistor it is 890 kohms not 890 ohmsFirstly, the resistor value is wrong - it should be 1MΩ not 890Ω, and the wiper should not be connected to the outer terminal of the pot. The circuit you have drawn will give 0 - 4.59V
To fix the noise, put a capacitor across between wiper and ground. A good few microfarads - as big as you like. If you make it too big, the output will be annoyingly slow to adjust.
LM358 is probably not the best choice of op-amp if you want it quiet. Go for a low noise op-amp!
The probe is clippedThat could at least partly be noise picked up on the probe lead.
Was the probe hand-held or clipped to the wiper?
Where is the probe ground clip connected?
"Turn up the timebase to see if there is any oscillations in the 100kHz to 1MHz region."That noise doesn't look quite random enough. LM358s don't like capacitive loads or driving long cables, especially at unity gain. Turn up the timebase to see if there is any oscillations in the 100kHz to 1MHz region.
Just look for a sine like wave and measure its period"Turn up the timebase to see if there is any oscillations in the 100kHz to 1MHz region."
There4 is no fft in my oscilloscope
DefinatelyLooks unstable to me - another reason to try a better op-amp!
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