Everything you need to know when buying/using an Oscilloscope! EB#49

Here are some things I would like to add to the video:

1. I do not want to shame low cost scopes in this video. I started with a 2 channel one from Rigol and it worked perfectly fine. Over the years though I noticed that 4 channel scopes are the way to go. And I also only got such expensive Keysight scopes since they gave them to me for free in order to support my work. So in a nutshell, you can start with a low cost scope just fine!

2. I heard that people would just insulate the PE connector when powering the scope in order to measure mains AC voltage. This is a TERRIBLE idea. This way you connect a possibly very high voltage to the BNC connectors. If you touch that, you have a problem because you can be partly or completely connected to PE. Only use a differential probe for that or use two scope channels and use the math function in order to calculate the difference between them.

Thanks for reading ;-)

Great video presentation! I'm a novice hobbyist, so this video was a bit outside of my comfort level. Do you happen to have a more basic tutorial on how to use oscilloscope to diagnose basic faults in individual circuit components? I bought an oscilloscope a few years ago, but I'm afraid of using it.

I understand that there is a switch for scaling on the probes and that on the oscilloscope you can select the v/div setting.
But I got confused about the section were you still didn't get the expected amplitude.
What was going on?

I was hoping you would talk about isolation transformers, please. Thanks, as usual, your videos are great.

In general good video,
I do not understand why you raised the PE topic, not mentioning that most new scopes (at least simple ones) work with USB supply where this should not harm.

kind greatings!

Just wondering do you mean that the power supply in an oscilloscope doesn't consist of an isolating power transformer of any sort?

Thanks, i now know how to use my 50 year old siemens oscilloscope.

RIGOL DS1054Z For the <£500 win :)

I have a 30 year old HP 500MHz scope that I really don't want to damage. I am living and working in Brazil nowadays; a country which has no earthing system! Am I right in thinking that my scope is safe? As long as I work on x10 to measure 127v or 220v? I do a lot of work with valves as well which work at around 400v.

I got brilliant ad on this video😂

I actually hookup the ground lead ALWAYS.
But i have to say i power the electronics with a isolation transformer (to work more safe).
Then you actually must connect the groundclip!

Why not use an inverter connected to a battery source to power the SMPS you are working on and probing? In that case the SMPS is not referenced to the Earth in your home and therefore not the one referenced in your oscilloscope. In which case you would not need differential probes? Or am I missing something?

Does Online UPS clean out dirty power and harmonic distortions ?

I let my 4-channel USB oscilloscope float 😅 350V common mode offset is no problem (of course I insulated the BNC connectors, the scope chassis... It can be VERY dangerous, be careful!). I use an insulated 5V power supply, built by coupling two motors through a piece of insulating material. The output of the second motor (a stepper) is rectified and sent to a 5V buck converter. This provides me with an insulated 5V that can withstand several kV common mode, and just as a battery powered device offers very low coupling at high frequency (EMI which could otherwise interfere with measurements). To insulate the USB, I use a board built around the Silana ICEUSB3. This only works for DC common mode though, as the ICEUSB3 chip doesn't work with fast fluctuations between ground planes... I may improve my setup with USB over fiber, not tested yet (that would also greatly improve the EMI).

Great video!

I have the exact same current clamp as the one you showed!

I found a nice 2 channel 200mhz Tektronix scope used for $200. It was only 2 years old when I bought it a year ago. I started with a Tektronix CRT scope. I used it for many years and still use it sometimes especially since when I need more than 2 channels. 90% of the time a 2 channel scope is all I need that’s why I went with a 2 channel.

The electrical ground wiring once had some meaning for protection if touching the metal casing of the scope to prevent leakage since a lot of high voltages were present.Nowadays in digital scopes with plastic covers what is the meaning of the live ground?I dont recommend the practice of ommiting the usage of the mains ground wiring since everyone who uses professional tools (and i instist on this) is responsible to treat his tools freely as long as he ensures that nobody will got hurt or cause damage to person,property or animals.

For my personal use, I cut the ground of a power strip that i use for the osciloscope, the diferencial prope is too expensive for my current use.

I use a Li-ion battery source of power on my oscilloscope, in this way I can be totally isolated from the mains and the source of noise it brings. My Owon SDS7102V has an integrated module of 2S Li-ion 6A enough for 1 hour of work. Or I can add and use a 10 S battery (from tools like Makita, Panasonic) via a step down converter to 8 V, in this case I have added a switch to not short circuit to the internal 2 S module.

This is a great video. However, it is for beginners and I would strongly recommend that beginners stay away from live mains voltage and high-voltage DC circuits - they can cause serious personal injury.

Awsone. You helped me purchase a scope. Simple concise. Excellent !!!!!!

so what was this even supposed to show us ?
the only thing that i got from the video was just a really r3t4rded voice pitch at the end of every sentence and nothing else whatsoever

My specialty is analog and mostly vacuum tube audio electronics and I've got a trusty old Hameg HM204 which is fine for that kind of work, but I saw its limitations when I tried to take a closer look at the sampling process when reverse-engineering the Sochor delay device. Who knows, maybe it's time for me to get a digital one?

Great scope tutorial! I will bookmark this video and send it out to any oscilloscope newbs I find.

Good content. I also love your t-shirt! Where did you get it?

Sehr gut erklärt!

electro boom would have commited to breaking at least one scope to do this video

Can we use isolation transformer for measuring mains voltage instead of differential probe?🤔

Great video!
For the basics I would add to adj. the cap in the probe for a correct square wave.

I appreciate your multi-color sketches as you present the topic. Always very well done! Very easy to listen to and educational :)

That was two sentences!

This is one of those tools I’ll buy first and find a use for later

Would be interested in your thoughts about cheap usb scopes with sigrok, such as the hantech scopes.

… so I shouldn’t have connected my pocket scope to mains voltage directly… oop

Whohoo for aMurica and our 120v system, a lot harder to blow up the scope lol!

What's PE? What's RCD? Never heard those terms.

Maybe I'm mistaken, but the connection you DIDN'T make wasn't to NEUTRAL but to the negative side of a bridge rectifier, no ? That means you would be connecting the "ground" of your scope to LIVE every negative half cycle. That isn't what you seemed to be showing when you illustrated it with the schematic. Many years ago in a moment of madness I did exactly that and the bang confused me for a moment until I realised that I had done the exact thing I had told myself not to do a mere 5 minutes prior. Big heavy valve scope survived - no surprise the bridge rectifier did not.

I love the exclamation at the beginning of the video when you plug the homemade switch mode PSU into the mains AC!!!!!

Also eigentlich sollte man vor das zu testende Gerät immer nen Trenntrafo hängen. Aus… „Gründen“… :)

Would a basic isolation transformer such as the type used in shaver sockets do the same thing?

hey @GreatScott your mug page is down :-)

I got a 4 channel PICOSCOPE which has all 4 channels totally isolated from each other, so hopefully that helps me to not blow it or me up.

Nothing with the name 'Keysight' is a budget option 🤣

Thank you so much for this valuable video!!

wtf 1400 euros for scope? wring choice for first (even 4th) oscilloscope

Would you recommend the hantek dso2d10?

Bitte nicht immer den Schraubendreher ans display halten, das macht mich super nervös (Bedonders wenn das Display 15000 kostst)