EEVblog - 2013-04-12
Dave cracks out the whiteboard and side cutters to explain two lesser known facts about x1 oscilloscope probes: - Why the bandwidth is much lower in x1 mode than x10 mode - Why oscilloscope probe cables aren't like ordinary coax cables Forum Topic: http://www.eevblog.com/forum/blog/eevblog-453-mysteries-of-x1-oscilloscope-probes-revealed EEVblog Main Web Site: http://www.eevblog.com EEVblog Amazon Store: http://astore.amazon.com/eevblogstore-20 Donations: http://www.eevblog.com/donations/ Projects: http://www.eevblog.com/projects/ Electronics Info Wiki: http://www.eevblog.com/wiki/
Yes, highly recommended. I wanted to cover the x1 mode issue that Doug and everyone else seem to skip in their talks that focus more on x10 probes.
I had so many issues with transmission line theory when i was working on my degree its a very difficult subject
I'd like to to point our for anyone interrested - Doug Ford has covered the topic very well in his article: "the secret world of osciloscope probes" by Doug Ford, go google it.
@25:18" It doesn't matter a rats ass" ... gold aussie Tech talk hehe love it
Now I am 10x more optimized to watch another EEVblog!
10x means divided by 10
Well, I had to walk toward the camera to turn it off anyway...
Yes, it's big subject actually, and you could spend ages investigating how it all works and is optimised for best performance.
Low level signal measurement, e.g. 1mV/DIV. With x10 you trade signal level for more bandwidth, so your scope becomes 10mV or 20mV/DIV minimum
No, usually not. Yes, the odd shuffle was required in this one.
I've been using scopes for twenty years and never knew this. I was taught to always use 10x because of the higher bandwidth, and noticed it on the datasheet, but never needed to take the time to figure out WHY.
Whenever I simulate things like this I am wondering if group delay should worry us too...
Good stuff, well explained and showed. Keep them up Dave!
I like the end, "I could have told you that at the start."
Dave, you've taught me so much about electronics. Thank you. I bet no one at my college will ever cover this!
Holy crap, I learnt so much! Thanks Dave! Btw: Could you do more videos like this?
Hi Dave,
You didn't do one thing when you damage this probe already: measure the whole lenght of this inner cable. You will be suprised how long is it!
He is a professional YouTuber. :)
Thank you! Please Dave continue with this stuff and explanations! Greetings from Bulgaria!
Good subject to investigate and a Great presentation! Thank You!
No, you can roll your own. I've done a video with Doug on high voltage probe design.
Mr. Jones, thank you! :D
Dave, that was hugely informative, thank you
Great video, thanks.
Dave's probing genius rocks! Thank you for the video!
Great! Thanks man.
I loved this video. I know a fair bit of theory and thought we were going to get into rise time limitations of the R/C compensation. I NEVER knew about the deliberately lossy transmission line. Dave, please do more theory vids.
Great tutorial thanks we learn somethings every day.!!
Thanks !
Excellent! As always! Thank you!
Please review your new JBC station :)))
Thanks for the information :)
Thanks again Dave.... Your video's are much appreciated. I learn so much information each time. Keep them coming... Your a fantastic TEACHER.
Yes, the 50ohm coax of course needs proper termination to work well, a whole other topic. As is the transmission line matching.
Oh the funny little hidden secrets you unveil for us. Thanks, Dave.
Man, I love these videos
Excellent video Dave!
Hi Dave, can you make some quick video on measurement of smd capacitors and coils?
Awesome video! The diagram with the lossy transmission line modeled as a series of RC circuits says it all.
No, it's all to do with transmission line matching and compensation. The probe is transmission line optimised for x10 mode, so is all mis-matched when you switch to x1.
Ah! So it is a question of frequency vs fidelity? Thank you ib9rt.
very useful stuff! Thanks
Nice One Dave!!! hahahah very usefulll I say hahaha because I suddenly remember this subject being taught and the teacher was boring so I didnt take much notice )))
Thank you Dave for this excellent video! I love all your videos but it is nice to pick things up like this which weren't discussed in the university (unfortunately). It may take some work but I'd hope the appreciation from the community encourages more in the future! Thanks!
Thank you Dave for pointing that out. It is useful to know the X1 is so low BW and that a coax is actually better in low volt and hi BW applications. Non intuitive. I love your blogs ( I love your accent, LOL). BTW, how do you pick coax for that condition. 50ohm, 75ohm, etc.
They have a special coax just for data transfer on satellites. Not sure of the resistance? but it has double braided Shield 100% copper with 100% copper wire in Center. It's about less than half the diameter of a TV cable wire.
Didn't think about that, yeah, I've swapped sides!
Very nice video, Keep it up.
Cool! thanks
Brilliant explanation Dave. It would be great to continue this by explaining differential probes, how they work and possibly design one to build. Low frequency of course.
c'est bon à savoir, et très intéressent
slinkytreekreeper - 2015-02-22
So many answer to questions I didn't know I wanted to ask until you asked answered them. Very groovy Mr Dave you got my sub for the ride