# Oscilloscope probes

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My company has an old Hitachi V212 oscilloscope. I found two online manuals one saying I needed the AT-10AQ probe and another saying the AT-10AJ probe. In our office I only found two AT-10AR probes, one working one broken. Could someone potentially elaborate the differences? Are there ways I can use different probes if i can identify the differences, and account for them in my results?

Also Ive seen a lot of 1x/10x probe nomenclature, does that refer to the "10" in the probe name, and is that reflective of the Gain?

Thanks

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Search net for "AT-10AQ probe" and "AT-10AJ probe" and you can find easily links to e.g. ebay where you can purchase them for $25-$30..

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Posted (edited)

This is a very old scope, designed for TV / Radio repair shops repairing analog TV,  radio and audio equipment, digital clocks etc.

What are you going to use it for ?

If you do not already know how to use it here is a Hitachi operation manual pdf

This decribes the correct use of the probes on page 17.

The probes appear to be fixed division (divide by10) capacitive input, so they will not be suitable for DC signals, or very slowly varying ones.

At x10 and x 1 probe will have a switch to divide by the signal by 1 or by 10.

The x means divide by not multiply by.

So you have to multiply by the same factor to get the true reading.

Edited by studiot

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Thanks Studiot. We manufacture silicon processing equipment and I will be attempting to identify noise, likely from the 750W amplifier.

It appears that my AT-10AR probe is insensitive by a factor of 10. (using a fresh 1.5V battery, it showed 0.15V trace), If you could elaborate further on why the cap input is not suitable I would greatly appreciate that. Does this mean It will be better for AC measurements?

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24 minutes ago, GM42489 said:

Thanks Studiot. We manufacture silicon processing equipment and I will be attempting to identify noise, likely from the 750W amplifier.

It appears that my AT-10AR probe is insensitive by a factor of 10. (using a fresh 1.5V battery, it showed 0.15V trace), If you could elaborate further on why the cap input is not suitable I would greatly appreciate that. Does this mean It will be better for AC measurements?

I'm afraid I'm not knowledgable about the manufacture of silicon products or why you would need such a power amp for the purpose.

At that power is it a class D or switching amp of some sort?

At 750 watts output (genuine RMS measure ? ) the switching frequencies and noise generation will be within the range of the scope.

Divide by 10 probes are used as the division also reduces the input capacitance of the measuring system by this factor.
Such reduction becomes more and more important the higher the frequency as it reduces signal distortion.

A competent electronics tech should understand this.

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I use my Hitachi V212, a V222 and three more oscilloscopes without any probes for general measurements that do not need high impedance load probes.  Perhaps your power supply is one of those too, giving screen readings that are true, not a tenth of the probed levels...

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20 hours ago, studiot said:

I'm afraid I'm not knowledgable about the manufacture of silicon products or why you would need such a power amp for the purpose.

At that power is it a class D or switching amp of some sort?

At 750 watts output (genuine RMS measure ? ) the switching frequencies and noise generation will be within the range of the scope.

Divide by 10 probes are used as the division also reduces the input capacitance of the measuring system by this factor.
Such reduction becomes more and more important the higher the frequency as it reduces signal distortion.

A competent electronics tech should understand this.

It is for the spindle motor. It is a class D amplifier. When my new probe arrives I will visualize the lost communication w.r.t. the amplifier's signal.

I am effectively our electronics tech, but I am certainly far from qualified. Thank you for your input.

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1 hour ago, GM42489 said:

It is for the spindle motor. It is a class D amplifier. When my new probe arrives I will visualize the lost communication w.r.t. the amplifier's signal.

I am effectively our electronics tech, but I am certainly far from qualified. Thank you for your input.

So does the amp control the speed of the motor?

One way to do this is to configure a power amp in a bridge (or other) variable oscillator circuit.
Varying the frequency of the supply to the motor varies the speed of the motor without loss of power.

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