How to use an oscilloscope

I just ran into this video series and he goes slowly through how to use an oscilloscope. Given there are a starting to get to be some decent basic low cost ones in the 50-100 range on the market and as one of the basic tools used for circuit design testing and repair. They are also used for auto repair. This might help someone.

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Thanks Sean, even that i own eight 'scopes (yes im an tool-maniac) it seems i can never learn enough how to use them, i also forget along the way…
Edit: just remembered, i only have seven oscilloscopes, one is burned dead… :roll_eyes:

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I honestly have only used a scope a few times. I got a cheap sco2 because I need to fix a few things, and apparently it does 10mhz signals and has two channels.

It isn’t something I have ever used with a vehicle, but after watching about half of this video that popped into my playlist, it makes sense why they are used, and the cheap one is woefully inadequate for some of the functions.

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Apparently the cheap scope I have has issues picking up square waves at about 60khz, I need at a minimum 108khz for this project. Might be a user error as it took me a bit to get the 60khz wave up on the screen. But it also doesn’t let you calibrate the probes. I am thinking it might go back.

I found an sds2012 for 100 bucks for 2 ports and 4 ports is 150. Is 1Ga/s 100mhz fast enough for autos and how important is having 4 inputs? The Owon/Hantek, etc supposedly actually sample at advertised rates.

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Im no expert on scopes, especially not on automotive troubleshoting, as i only used specialized automotive industry ones in that way, Bosch, and like.
The ones i own are all “classical” crt scopes, all but one is 2 channels, i think my highest rating is around 60mHz.
I really need to check my “precious” military surplus, radar repair scope, that was the highest top standard in 1960s :smiling_face: (i bought it never used, with calibration certificate for $4…
In auto troubleshoting/tuning 4 channels absolutely has it’s benefits, there often many “signals”/feedback needed to watch.
About rate for autos i hope SteveU may help us out, i believe he has the expertise.
Me, i’ve mostly read out o2 sensors, throttle positions, wheel speed sensors, pretty basic stuff. Not the advanced, getting in to the computer comunication stuff, CAN, Lin, VAN, and all that, there my computer translate for me :woozy_face:

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The software on the pc was doing the decoding on a couple of the example in the videos. I highly suspect that software was built using labview which can decode canbus which in =theory= could replace a some of the gizmos you use. :slight_smile:

I am really just debating on whether it is worth it to spend the extra 50 bucks to get 4 channels and decoding signals, monitoring multiple signals simultaneously might be important enough to justify it.

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This is the one I think I am going to get. about 2:45 in, he test AC mains, then at about 3:00, he tests the output of a battery inverter… You see the difference in the waveforms. lol

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Thanks Sean. Electronics are mostly to far out of my comfort zone. This one might help in some cases.

Off topic, what is Vevor? The new Alie Express?

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I think electronics are out of a lot of peoples comfort zone. This helps to know what is being sent electrically and especially being able to visualize it. And you can save the data which means you can do other analysis on it, but I mainly got it to check out waves and frequencies to figure out what is being sent. But it looks like for vehicles you can do more advanced tuning and diagnosis.

I think Vevor is a chinese company that rebadges and sells under their brand name so they only have one listing per item. It is the vevor store, with only vevor store brand products. So like amazon that only sells amazon basics. Sears used to do it that way with all the sears branded stuff. Aldi’s is similar but they have multiple brand names they use, that they own.

Aliexpress is a flea market with multiple vendors selling the same item.

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Apparently, someone wrote a book for vehicle hacking, that supposedly explains how vehicle electronics work, but it is dated a bit as it was written in 2016.
https://www.amazon.com/Car-Hackers-Handbook-Penetration-Tester/dp/1593277032

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here is an article that uses arduino’s to set up your own very basic canbus network. (you don’t have to use an arduino it should work in the arduino ide)
https://medium.com/@esebranek/creating-a-diy-can-533f8b5656b9

Since this thread is more about scopes. this is an arduino signal generator code which I was using with the esp32 to test the scope.
https://www.ufrjnautilus.com/post/como-fazer-um-gerador-de-funções-simples-com-arduino

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It looks like sigrok/pulseview will decode canbus messages over scpi which is the output from the scope. sigrok apparently decodes quite a few protocols, most I have never heard of but there are several automotive ones like LIN, FlexRay, EiBus, etc.

https://sigrok.org/wiki/Protocol_decoders

Just need to make sure there is a driver, and if it is a rebadged siglent. there is.

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Maybe a little off topic, but does anyone know how to use the microphone jack on a computer for data acquisition?
Rindert

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what kind of data?

here is a linux soundcard oscilloscope. If you just want to capture data, I think you just record and save to a non-compressed audio format, .wav seems to be popular. (the compressed ones trim the audio level to the normal hearing range) and use a similar setup to what they have setup in this video.

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Thanks Sean.
(20 characters)

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My scope is a rebadged OWON sds1104. But apparently they switched the 5 day sales to a month long father’s day sale. And as of right now, the sigrok is not working with my scope, but I was able to access the SCPI using GoLang library. The sigrok project seems to be a bit sketchy about adding hardware, and if I do the work, I want it included.

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