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I keep hitting a wall on my projects where I can't really tell what's going on and decided I really need an oscilloscope to proceed intelligently.

I've got a Rigol DS1052E in the mail after a few recommendations. I know the kinds of things I need to measure, but I want to make sure I don't blow it up the first day.

What kinds of tips do you guys have for effectively using a scope and avoiding damage to it while getting useful information out of things?

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    \$\begingroup\$ Flagged for community wiki conversion, as there is no right answer. \$\endgroup\$ – tyblu Nov 7 '11 at 7:20
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    \$\begingroup\$ @tyblu but there are wrong answers. That implies that all non-wrong answers are right answers, no? Thus, yes, it does have right answers. \$\endgroup\$ – tuskiomi Dec 15 '16 at 16:12
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I've never damaged or heard of anyone damaging an oscilloscope.

If the scope has a 3-prong connector, don't connect the ground lead to something that isn't at Earth ground, or you'll blow some fuses and burn up the alligator clip.

If you're being stupid and floating the scope to measure something not at ground potential, don't leave an alligator clip hanging freely to brush against the chassis. :D

Don't connect it to anything greater than the voltage limit on the front of the scope (400 V).

Don't clip the probes to something and then let their weight + leverage bend and break the clip tip. I'd like to know of better ways to do this.

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    \$\begingroup\$ I have heard of sophomore electrical engineers(our first year to take electrical labs or classes) blowing fuses by connecting their ground probe to something that was not ground and had a lot of power behind it. \$\endgroup\$ – Kortuk Nov 7 '11 at 8:17
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    \$\begingroup\$ Remember both earth clips are connected together within the scope. \$\endgroup\$ – Martin Nov 7 '11 at 8:44
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    \$\begingroup\$ Being in a somewhat similar situation (and actually about to order the exact same scope), I've been doing a bit of reading, and found these tutorials here to be quite enlightening. Might like to check them out. Also one here, and finally this doc. \$\endgroup\$ – icarus74 Nov 7 '11 at 17:15
  • \$\begingroup\$ A bachelor student at my lab fried an oscilloscopy by directly connecting HV (~10kV if i recall correctly) to the inputs (good thing that she only fried the scope and not herself) ... \$\endgroup\$ – etarion Nov 8 '11 at 12:32
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Scopes are pretty hard to blow up unless possibly you are working with circuitry directly connected to the power line (not thru a transformer or other isolated power supply).

Ordinarly scope probes are usually switchable between x1 and x10. What is being multiplied is the impedance, not the voltage as you might think at first glance. The voltage is multiplied by the inverse. A x1 probe therefore has the impedance on the label (usually around 1 MΩ and 10-20 pF) and passes the voltage directly. A x10 probe has 10 times the impedance and attenuates the measured voltage by 10 before passing it to the scope. Therefore if you're not sure what voltage the circuit is, start by putting all the probes on the x10 setting and choose a high voltage scale. Since digital scopes can do math, nowadays you tell the scope (or fancy ones can sense for themselves) what setting your probe is and it automatically adjusts the voltage scale accordingly. For example, the 5 V/div setting for a x1 probe automatically becomes 50 V/div and is displayed that way when using a x10 probe.

Otherwise there is little you can do to hurt a scope. Getting a useful display for various conditions is something else to learn. When I don't know much about the signal or am just using the scope more like a voltmeter because it's already on and sitting on my bench, I usually keep it at x1 probe, 1 V/div vertical, 1 ms/div horizontal, auto trigger, with the vertical offset adjusted so ground is one or two divisions from the bottom.

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