Hello All,
One of the Oscilloscopes that I am using has an issue with the Channel 1 input. When nothing is connected to the scope probe on Channel 1 the trace starts to ramp up very slowly indefinitely. When the scope probe is connected to a circuit there is an offset voltage of ~100mV. I have confirmed that there is not actually any voltage on the probes to cause this offset with a calibrated multi-meter and by using another channel on the scope.
Another weird thing is that when I connect my USB Drive with a metallic housing I see a charge/discharge to the ground on the scope trace. When I connect my USB Drive with a plastic housing nothing happens.
Here is the 100mV offset voltage with the probe connected to a circuit/device but no actual voltage there.
Here is the Trace with a slight drift. It is a little tough to tell completely because of the small time base.
This is what happens when I connect/disconnect the USB with a metallic housing.
Here is what the connection/disconnection looks like with a larger time-base.
Could this issue be coming from an overvoltage condition on the scope channel? What component of the input circuitry has been damaged, if any? No other channel has this issue and the scope can handle 300Vrms.
One of the Oscilloscopes that I am using has an issue with the Channel 1 input. When nothing is connected to the scope probe on Channel 1 the trace starts to ramp up very slowly indefinitely. When the scope probe is connected to a circuit there is an offset voltage of ~100mV. I have confirmed that there is not actually any voltage on the probes to cause this offset with a calibrated multi-meter and by using another channel on the scope.
Another weird thing is that when I connect my USB Drive with a metallic housing I see a charge/discharge to the ground on the scope trace. When I connect my USB Drive with a plastic housing nothing happens.
Here is the 100mV offset voltage with the probe connected to a circuit/device but no actual voltage there.
Here is the Trace with a slight drift. It is a little tough to tell completely because of the small time base.
This is what happens when I connect/disconnect the USB with a metallic housing.
Here is what the connection/disconnection looks like with a larger time-base.
Could this issue be coming from an overvoltage condition on the scope channel? What component of the input circuitry has been damaged, if any? No other channel has this issue and the scope can handle 300Vrms.