I want to build a high voltage probe to calibrate my 1.5Kv oscilloscope CRT supply voltage.
Will just use this probe once to calibrate the scope so I don’t want to spend $200 on a probe and I mind the safety risks that it may involve.
Have seen several project examples. Some use several small resistors in series with capacitors in between. Others just resistors. Other just one HV resistor.
But before building anything I should consider what fits my multimeter DC Input Impedance which is 7.8MOhm, right?
So what I need is basically a voltage divider capable of reducing the voltage 10 times. A 70MOhm probe should achieve the 10x attenuation and bring 1.5kv down to 150v if I am not wrong.
I am planning to use one 50MOhm and one 20MOhm in series. Both High voltage resistors, rated at 1.5Kv and 1/2W. Not planning to use any capacitors as well.
Frequency wise will I have any issues considering just this one time CRT calibration?
Is it worth a shot?
Will just use this probe once to calibrate the scope so I don’t want to spend $200 on a probe and I mind the safety risks that it may involve.
Have seen several project examples. Some use several small resistors in series with capacitors in between. Others just resistors. Other just one HV resistor.
But before building anything I should consider what fits my multimeter DC Input Impedance which is 7.8MOhm, right?
So what I need is basically a voltage divider capable of reducing the voltage 10 times. A 70MOhm probe should achieve the 10x attenuation and bring 1.5kv down to 150v if I am not wrong.
I am planning to use one 50MOhm and one 20MOhm in series. Both High voltage resistors, rated at 1.5Kv and 1/2W. Not planning to use any capacitors as well.
Frequency wise will I have any issues considering just this one time CRT calibration?
Is it worth a shot?
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