EEVblog

[@matth3wc]

So many times I accidentally left my probes in 1x, and my scope is set to 10x or the other way around. And I sit there looking at my circuit thinking something is really wrong then I realize it's just that.....

[@Basement-Science]

I've resorted to electrical tapeing the switch in the 10x position. I switch to 1x so rarely that most times it gets switched accidentally.

[@Kirillissimus]

And the worst part is that the switches are generally so flimsy that they are quite easy to get messed up by accident. Sometimes you just barely touch it and the switch just hangs somewhere in the middle between 2 positions making intermittent contact and producing noise on the oscilloscope screen when you probe around. I always hated the stupid things when they did that! And at the same time at least in my electronics diagnostics practice I discovered that a 1x probe is almost never needed because if the signal is so low that you can't see it with 10x then its source is most likely too sensitive to measure correctly as well forcing you to choose some point where the signal is already somwhat isolated and amplified. In the end I just completely switched to 10x fixed probes and just BNC-terminated pieces of a 50ohm coax cable for radio stuff. They save a lot of trouble by being much more reliable and with at least somewhat modern oscilloscopes they have almost no real downsides to them.

[@lhxperimental]

There should be something like "caps lock is on" warning on windows login

[@matth3wc]

@@Kirillissimus right? At my University, if you so much as look at the probe it would switch itself. I taped them down on those ones

[@Kirillissimus]

@@lhxperimental All my fixed 10x probes, the made in Taiwan HP9251-s, have a body made of green plastic as an indication of being the safe ones (you simply look at them and see "green => ok"). The older switcheable ones are all black or gray. It would be nice if all manufacturers agreed to use some uniform probe color coding. Something like 10x - green (safe), 1x - black (obsolete), 100x - red (danger, HV), current probes - yellow (safe to the scope but can be dangerous to you), blue or purple for capacitively coupled specialized probes and white or gray for other specialized probes. But as far as I know they never did.

[@Afrotechmods]

Great video and I love your probe collection. I have found that X1 attenuation instead of X10 can also be useful in high EMI environments because the lower impedance makes them less susceptible to stray fields. Look forward to seeing part 2 of this series!

[@userPrehistoricman]

For sure. 1x is like the probe underdog since everybody naturally grabs the x10

[@uzaiyaro]

Oh hey, you are alive!

[@Bllinker]

About that 1k resistive probe: One of my professors who spent his career doing high-speed analog stuff and who started in the 80s (when the access to proper, professional equipment vas very limited over here) made a couple of those probes. He based them on a piece of stripline on FR4 in a plastic syringe to get something like an actual probe (with a very short ground lead, I think he used a thin nail or a needle for that and for the actual probe tip) with the coax attached to the other end of the syringe. So, anyway, he recommends: -putting a 100-120nF cap right after the input resistor(s) to stop the probe from loading down the circuit at DC (because if you're using this probe you probably don't care about DC) -if you care about having 20:1 and not 21:1 nominal attenuation, using two 0805 resistors in parallel so that they add up to 950Ω (like a 1k and an 18k) He claims that the plastic syringe version has a bandwidth of around 1GHz (he used it with a 500MHz oscilloscope), but a better one made with a brass tube instead of the syringe had a bandwidth of around 2.5GHz, limited by the (fairly elastic) coax he used. Any comment on the use of those caps to limit DC loading of the circuit, Dave?

[@EEVblog]

You can of course AC couple, but I have not measured the performance myself. You don't want resistors in paralell as I think I mentioned in the video, as that adds to the tip capacitance, you want them in series.

[@izimsi]

Dr Burd? ;)

[@victortitov1740]

@@EEVblog By the time you start worrying about resistor's capacitance loading your circuit, you will already have serious issues with signal integrity due to said capacitance shunting out the resistor and affecting the attenuation ratio. SMD resistors can be stacked atop each other with almost no contribution to capacitance. But yes, indeed, series connection can be beneficial.

[@Bllinker]

@@izimsi Indeed

[@electrofan7180]

You can easily find ~950 ohm resistor in a bunch of common imprecise 5-20% 1K resistors. No need to connect anything in parallel or in series.

[@YoutubeBorkedMyOldHandle_why]

I've been beating my head against a wall trying to justify spending $400 on an oscilloscope, and here's Dave casually using 2 x $15,000 scopes and another worth $2000+. Thanks Dave ... I needed that!

[@sandalcandal281]

Love these educational, tutorial and guide type videos. Here's a comment for the engagement. Keep it coming!

[@martylawson1638]

The restive transmission line probe is my favorite way to make a built in high speed test point. Because of cell-phones there are some absolutely TINY coax connectors. Many are less than 2.5mm on a side. Add a series resistor and you've got a GHz bandwidth test point for 30-60 cents in < 10mm^2 that securely hooks to the scope with a $5-10 of coax adapters. Easy to AC couple the test point as well, just "tent" a resistor and a cap in series.

[@RickB3n]

Greetings from the algorithm 😂👍

[@bobimnottellin362]

I'm stealing that. The Algorithm giveth, the user taketh away. Circle of life stuff, right? Hakuna Matata.

[@bostedtap8399]

Great vlog, nearly everyone, including me (noob), concentrates on the scope settings to solve issues. I remember you showed the special squiggly wire used in their construction. Always to go back to basics, or advanced for me. Thanks for sharing.

[@TheCod3r]

The awesome crazy Aussie guy. Keep up the great work bud

[@jeffm2787]

Good video, glad to see some of the older style content back.

[@jope4009]

What is "older style content"?

[@jeffm2787]

@@jope4009 Test equipment I guess. One of Dave's video's I remember the most is on the old 50Mhz Rigol scope. DS1052E I think it was. Just good to see stuff that can be applied vs well solar roadways or stuff while interesting can't be used in my daily life outside of re-affirming people are stupid 😁

[@bobpitt1261]

Excellent video Dave, thanks.

[@pappakilo3965]

I like your EEVblog HV probe. This time 20 years ago I'd've sold my Mother for one of those for a testing/measurement job we had to do at very short notice. I might even have included our cat and next door's budgie if somebody had promised next day delivery

[@originalgrantbob]

Thanks Dave. Good explanations and I'm sure a reference I'll end up coming back to.

[@spicemasterii6775]

KEYSIGHT. Eevblog has come a long way from Rigols. Congrats on your success and an amazing channel, Dave.

[@terrygould3230]

More videos like this please! Been missing your tutorials and equipment demos etc. Keep up the good work!

[@sanjursan]

With a 10X probe and an analog scope with a best volts/div of 5mv it is not much fun trying to measure DC ripple! I use an old analog Hp 412A chopper circuit meter which goes down to 1 millivolt FULL SCALE. It is a lovely, amazingly accurate unit with six ranges below 1 volt! Hypnotic to watch that needle dancing back and forth.

[@johngreen1060]

Impedance of a terminated 50 ohm coax is a flat 50 ohm resistance (none of that 100pF bollocks). I recommend using another 50 ohm resistor at the input of the coax to dissipate any reflections scope termination might have produced (that will halve the gain, though) and add a good quality dc blocking cap. No need to build a new cable, just modify an SMA connector and screw it into any SMA/3.5mm cable.

[@PilotPlater]

Coax transmission lines, Dave you're approaching the territory of RF woowoo magic!

[@pawpawpascal1524]

(as a relative newb here) I love these videos that tee off a full day of Dave videos in the links 😸

[@eebaker699]

Great video. I found this very helpful especially for a beginner hobbyist as myself. Look forward to part 2 and more interesting discussions. Thanks.😬

[@TobyRobb]

From my learning about amateur radio coax versus ladder line, you cant expect the shield to fluctuate with AC. It should be tied to ground and the centre pin should go positive and negative with respect to it. With separate conductors EG ladder line, both conductors can go positive or negative. Hence the need for a balun when going between conductor types..

[@TobyRobb]

@Ken Mason I'm definitely the amateur in amateur radio. I just thought I would offer my thoughts on coax. But I think there's some issues there that I'll leave up to you.

[@aeroscience9834]

This was great! Learned a lot

[@prathikprashanth2932]

excellent tutorial as always :) keep 'em coming!

[@nigeljohnson9820]

You may have missed one, I have found it useful to have a diode RF probe that can be connected to the oscilloscope. Very handy for looking for modulated RF signals on a limited bandwidth scope.

[@namibjDerEchte]

That's an active probe, IMO. A very crude and limited active probe, but nonetheless.

[@nigeljohnson9820]

@@namibjDerEchte I disagree about the probe being a crude instrument. It was very handy as a quick monitor for TDMA digital radio signal. When developing TETRA, we had access to very expensive signal analyses, that could display time and frequency domain information, including constellation diagrams, vector error, and message error rates, etc but as a quick test of the carrier modulation, a diode probe connected to an oscilloscope was invaluable. It also has its uses, in probing RF oscillators, if stripes and looking at the locking characteristics of phase locked loop a, where it is the RF envelope that is of interest.

[@erikdenhouter]

The ones with the red attenuator switches have their 1x setting when pushed forward. That can blow your scope (mine is 250V max.) when you want to measure higher voltages, because you can put pressure on the switch while measuring, and you will push it from 10x to 1x. I have just removed the red knob (you pull it off easy) , and use a little screwdriver to actuate the switch now.

[@Thats_Mr_Random_Person_to_you]

Hope your recent community posts boosted your page!!!!

[@EEVblog]

Doesn'tseem to have at this stage.

[@Thats_Mr_Random_Person_to_you]

@@EEVblog heres hoping its more of a 'long game' and over the next week or so it starts to show! Either way, love this vid. I've learnt new things from this and thank you for the education!

[@notsonominal]

@@EEVblog kittens, more kittens!

[@clems6989]

Great video.....Thanks !

[@BarackBananabama]

I like this topic! When I see it I knew I'll love it!

[@JesusvonNazaret]

A couple years ago Rigol had the best bang for buck in entry level 4 channel scopes, now there are so many new affordable scopes on the market and I wonder which one would be the best bang for buck (with the least amount of annoying "features"). I think there is room and demand for such a comparison video every 5 years or so.

[@nicksokolov6024]

Good work Dave... I am not immune from asking "stupid question" when looking at circuit. In my 60ies I make occasional 20y old mistake - no one is immune. I have 4 of those type probes.. one is differential , one is current - all purchased away from my wifes asking ; and how much was that toy, haven't you got enough!!! Between you and I Dave one can never have enough probes. Currently Trying to fix (4off) EPSON theater projector EH-TW5700 with no EPSON repair center manual anyway I need to fill in time after 65y+ until the elevator to a pub with warm (or no ) beer ....Pub run by guy named Old Nick It's all fun - keep up your blogs It keeps me going. I agree...Good enough for Australia and Gina Rinehart

[@KeritechElectronics]

Mighty awesome, I loved it! Very informative.

[@galileo_rs]

Only a half an hour long video? And here's me prepared for a 2h long marathon with a bag of popcorn ;)

[@Xsses]

21:10 In analog scopes, you always had to calculate the voltage manually and no one was complaining.

[@vonnikon]

You can also make a differential isolated AC-coupled high bandwidth DIY transmission line probe. How you ask? Connect a cheap ethernet transformer to the tip of your coax. You can even get some spectacular impedances by using other turn ratios than 1:1 in combination with suitable resistors.

[@TheRich464]

First time I got an add from youtube to pay them money to not see there (or other) ads.

[@berndrosgen1713]

Great summary!

[@electronic7979]

Helpful video 👍

[@d.jeffdionne]

Most of the time, looking at high speed digital signals is best done with a Z0 probe. I call them a "cable launch" probe, but that's just me. You can even look at things like Gbit/sec LVDS with them, and they cost (basically) $0. I previously did a little analysis with SPICE just to see ground lead length and the effect of the capacitance of common resistor (physical) sizes do to the frequency response... and the answer is it basically doesn't matter. Another thing that is useful to do when designing the board if you know you'll need to probe for example a high speed SERDES interconnect is to put some pads there for a 0402 size 953ohm resistor and a ground via close to it :) For cables 1/10w 380ohm in series with 570ohm makes for a 20:1 with 1/2 the parasitic capacitance of the resistors.

[@MacRabbitPro]

Now we need a tutorial video on how to properly build such a home made times 10 high frequency probe... :-)

[@jonniecypher5488]

Totally off topic but I have to say your voice is very similar to Shirley Strawn's of Skyhooks fame. Keeps me listening because it's as if he lives on but now as an electronics enthusiast! Cheers

[@dwarslopers]

Ähhh, RG174 at 1GHz should have an impedance of 50 Ohm. You just considered the C part only, but there is always a L part as well. So a little bit more than 1,59 Ohms.

[@TheHuesSciTech]

Pro tip: wrap your 1/10x switchable probe with duct tape. Hooray, it's now a fixed 10x probe!

[@sanjursan]

Lol, nice one. Ya, then get something from the P6000 series to get real work done.

[@userPrehistoricman]

KEYSIGHT HATES HIM!!! LEARN THIS ONE SIMPLE TRICK

[@gustavrsh]

5 Types of Oscilloscope Passive Probes I don't own

[@Kirillissimus]

How do you even use your oscilloscope then? :)

[@gustavrsh]

What oscilloscope?

[@eDoc2020]

@@gustavrsh That reminds me, I got my oscilloscope probes before I got my oscilloscope. The used probes were being sold at a nice price and I predicted if I found a good deal on a used scope it would come without probes. It turns out I was right.

[@James-wb1iq]

Thanks - this is great.

[@PlasmaHH]

I just wanted to link that one video but can't find it. Its from I think a tectronix guy, greybeard, who goes into a lot of intresting details about divider probes and how you have special lossy coax and all sorts of things to increase the bandwidth.

[@tuttocrafting]

Is this the new camera? Is so fast and precise on autofocus!

[@EEVblog]

No, my old NX80

[@logikgr]

When driving a car with manual transmission, and one shifts into a lower numerical gear, 5->2 instead of 5->4, it's called a "money shift." What's the equivalent phrase for when one blows up their scope because of error with probe?

[@HighestRank]

Forgot the isolation transformer, too cheap for varistor, & ground the clip. POST: Power On Sizzle Test.

[@Aparviel]

Hi Dave, great video! Waiting for part 2 and review/test of Micsig DP10007 which you teased a few videos back, wanna see is it any good

[@imagineaworld]

I was told 5 and I got 8, what a treat

[@PattysLab]

The standard probes that I got with my RIGOL DS1054 were so poorly made that I had to bend the spring in the little hook attachement in order to not let the signal fluctuate..

[@Adrian_Finn]

Late reply but I had to do exactly the same with all four of mine.

[@MrDoneboy]

"Come a gutser"!

[@chrisg6597]

And then there's also system bandwidth to consider. Example, If you have a 200Mhz scope with 200Mhz probes, don't expect to measure 200Mhz signals. The bandwidth may only be 141Mhz.

[@volodymyrzakolodyazhny]

Yes, but it depends.

[@chrisg6597]

@@volodymyrzakolodyazhny Your right, that's why I say may only be. With old analogue scopes it was probably easier to define, but with digital scopes, that's a different matter. It may be that the input filter/amplifier has a higher bandwidth than that defined by maximum sample frequency. Also scopes that are software bandwidth upgradable, eg 100Mhz to 200Mhz, should in theory have more analogue bandwidth available if you have the base 100Mhz version of the scope. Keysight article of some of the problems community.keysight.com/community/keysight-blogs/oscilloscopes/blog/2016/09/01/what-is-oscilloscope-system-bandwidth-and-how-do-i-find-the-bandwidth-of-the-scope-probe

[@mishun]

19:35 Maybe I misunderstand something, but doesn't directly connected cable behave like 50 Ohm resistor since cable length is quite significant compared to wavelength at least if we ignore losses? (and that's also probably a necessity for that resistor divider to have constant attenuation over different frequencies)

[@namibjDerEchte]

I'd have thought so.

[@MarianKeller]

1 GHz? Say hello to the R&S RT-ZZ80 8 GHz passive 10:1 Probe.

[@AndrewZonenberg]

That's a transmission line probe. Same architecture as the DIY'd coax one, just made with more precise tolerances.

[@trentjackson4816]

I have to show support simply because I am ☆Australian☆ too... I run a DSO and a CRO on a budget. 2K would buy my lab and 20K would pay for my parts on hand.

[@Sheevlord]

It's not like I'd want to stick a probe into a 300 MHz 5 KV signal source, even if the probe was able to measure it.

[@matth3wc]

Right? My thoughts exactly

[@namibjDerEchte]

@@matth3wc It'd roast you by it's microwave radiation, right?

[@matth3wc]

@@namibjDerEchte ....what? Even though it's high voltage and frequency doesn't mean it has microwaves that will cook you. And 300 MHz is far below the microwave range. Though, every microchip leaks emf to some degree but this is in the nano range unless it's specifically designed to emit that radiation like radio towers or phones etc. It takes specially designed circuits and components to produce microwaves powerful enough to cook you. Your microwave has a magnetron to do this. The reason I wouldn't want to plug probes into something that high of voltage is , the higher the voltage the more dangerous it is (of electrocution) higher voltage can breakdown things that are supposed to be insulators and also makes it easier to find a path to ground. And not always but high voltage could mean high current which will definitely cook your body (not by microwaves though but actual electricity passing through your body). At best it would melt the probes and at worst it would kill you.

[@Broken_Yugo]

At that level you can probably just clip the ground lead to the probe tip and hold it a few feet back if you just need to see the waveform. Add a few turns of solid core wire and it can work on sensitive low power rf stuff too.

[@namibjDerEchte]

@@matth3wcSorry for the late response, am surprised to find one like yours randomly stopping by this comment section again: It's just 3x lower frequency than some commercial microwave ovens (~900 MHz). It doesn't take specially designed circuits to radiate thermally dangerous amounts of near-field EMI from a 5 kV AC RMS node that lets you stick a probe in there, because this implies a certain lack of tight shielding (or the 5 kV would arc/corona discharge at high-field boundaries associated with a narrow probe hole in otherwise tight shielding). Even across a massive 10 kOhm system impedance where it occurs, that'd be 2.5 kW. It'd be 500 kW if measured across a classic 50 Ohm system impedance. And you'll have difficulties handling even 300 MHz at such large system impedaces. It's likely just for transients on few-kV MOSFET/IGBT inverters for industrial or electric train applications, where the high frequencies have very low duty cycle due to only being the ringing experienced at switching edges.

[@matth3wc]

Who needs probes? I just slap the circuit against the inputs on the scope....no probes needed! 😂😂😉

[@shaunhagan1610]

Very good video…

[@danedewaard8215]

Fantastic!!!

[@my3dprintedlife]

Someday I'll have a proper scope.

[@rbmwiv]

My Tektronix has the spot for the nice probes. I have just stuck with the ones that came with it.

[@Diego-kj4ip]

With the DIY probe of 21 attenuation you could perhaps make a calculation using a reference value on another channel...

[@frankgrudge8823]

Superstar Dave thanks

[@jj74qformerlyjailbreak3]

I wish I knew more about probes before I bought an antique 10m scope. Dumont 2100g. No wonder I get nothing.

[@gelecopter]

Basically, the only new principle involved is that instead of the power being generated by the relaxive motion of conductors and fluxes, it is produced by the modial interactions of magneto-reluctance and capacitive directance.

[@SomeRandomPerson163]

20:03 I guess it incorrect to handle long transmission line like simply capacitor. It also have distributive inductanse. So we have 50 or 75 ohms in stadard cables. It mean on 1 GHz you dont need tec probe with 40 ohm load you can just use 50 ohm cable with 50 ohm terminator on scope side. All you need just check datasheet for cable to know how much dB per meter it eats.

[@eamonegan3955]

I went through the comments to see if anyone else made that observation. Yes - a 50 ohm input with a 50 ohm coax on it will look like 50 ohms resistive, there will not be any shunt capacitance.

[@tuttocrafting]

Let us know if the Algorithm (TM) will reward you!

[@EEVblog]

Not yet.

[@HighestRank]

AI*-gorithm©️®️™️

[@walkabout16]

Of all the tools used in a repair set-up Oscilloscopes are the least used, they are really only expensive ornaments

[@tom23rd]

Passive oscilloscope probe ASMR

[@jgurtz]

I wonder how LMR cable would be for diy probes. Very good for ham radio antenna connections

[@sanjursan]

My Tektronix P6011 1X probes are good to a bit over 25 Meg Hz.

[@GTechno13]

Is the next video going to be active probes? I'd like to be able to measure current and I think I need an active differential probe (and a shunt) but I'm not sure!

[@EEVblog]

Yes, finishing the edit now.

[@GTechno13]

@@EEVblog Sorry, dumb comment. I didn't have time to watch the video when I commented!

[@johncundiss9098]

"You gonna wire it for 220?" "220 221, Whatever it takes." Mr. Mom. The movie.

[@henke37]

Looks like the maker of DaveCad has expanded to mathematics with DaveCalc.

[@DarkRavenhaft]

"Came with your low end scope" has it plugged into a keysight. lol

[@rfmerrill]

The big difference between the active probe and the coax probe is because the signal goes high z for a period right? The coax has 1050ohm impedance down to DC so it pulls the net down while the fet probe has a much higher DC impedance?

[@volodymyrzakolodyazhny]

Active probes usually have low input capacitance and 1x at the same time.

[@eamonegan3955]

That's what I was going to say (bus goes high-Z),

[@AngDavies]

Does the attenuation from the finite bandwidth of the scope combine with the attenuation of the finite bandwidth of the probe to get something lesser? Like stacking filters?

[@alansmith4734]

Aliens love probes! 4 out of 5 toothless abductees agree.

[@MusicManSgtD]

Is there a website that has project circuit boards? I have been building kits up to now and am looking to take it to the next level. I want to peruse circuit boards and I can source the parts.

[@Infinitesap]

Did you connect the wrist ground on below your desk to actual ground?

[@brewman467]

How about Video about Rogowski probes?

[@Mike-ry4ti]

The algorithm wants me to see your probe.

[@oshosanyamichael9589]

Just watched this video without understanding a thing, guess I'd have to rewatch again. Sad I don't know crap about scopes

[@Neuroszima]

how about putting a potentiometer in series like that 19:00

[@Ender_Wiggin]

woooow quality content, why you do this to me !

[@matth3wc]

....I sometimes accidentally use the word puffs at work or in my master level classes and everyone just goes quiet trying to figure out what I meant. Then I'm like oh ...sorry I meant pico

[@tuttocrafting]

I don't even have a scope. I really should buy one. Scope first or a beach psu? 🤔

[@EEVblog]

PSU you can just DIY or scrap together, a scope gives you a window into a new world.

[@tuttocrafting]

@@EEVblog Thanks! A video about series vs parallel termination would be awesome! I'm absolutely noob on this!

[@Kirillissimus]

A multimeter comes first. Then some hand tools, spare parts, pieces of wire an some boxes for old broken electronics parts and bits. Then some proper soldering gear. Then a bench PSU, and only then I would start thinking about an oscilloscope.

[@eDoc2020]

For your very first oscilloscope I'd consider a sound card oscilloscope. It's basically a two-resistor divider connected to your computer's audio input. Compared to real oscilloscopes it's very limited due to the sampling rate, but it's super cheap and can even be made out of scrap. What's really nice is you get full digital storage functionality.

[@angelluismarin4365]

Can those probes be used with AC?

[@TheChipburner]

RG174 probe will not work on ordinary oscilloscope

[@WarpRadio]

impedance in DC? (did I miss a memo here?) ;)

[@jwlarocque]

Genuine comment here

[@Евгений-м2м2к]

Please turn on subtitles :)

[@joegrow9998]

REFLRCTIONS??? oh boy do I KNOW REFLECTIONS!!🤣🤣🤣🤣

[@frankowalker4662]

I can only afford the cheap Chineseum probs. LOL.

[@BarackBananabama]

5:20 "specilised" You need to sell an oscilloscope and buy yourself a spell checker if you don't like those free ones.

[@johnplaid648]

I'm a boneheaded. Wear deux the boneheaded go to understand just what uh oscilloscope is 4?

[@hamesparde9888]

I love my cat! I hate new metal! Thrash for life!

[@daltl3716]

Damn and i've always used x1 just because i didn't like the idea of x10 hahahah. No idea there was any big difference other than looking at weak signals. Why am I even going to college? Don't even teach me simple things like that. Is there any reason to really use x1?

[@nicksokolov6024]

watch this again good enough for csiro and "stralia" I am a fan boy -Dave

[@squidcaps4308]

heh... "1x bandwidth is hopeless, can't even measure 20MHz PSU noise".. Nah, it is plenty, so much more than an audio engineer needs.. There are signals and then there are signals and i find it so funny to hear someone say 20MHz is too slow..

[@volodymyrzakolodyazhny]

1x probe can load a circuit too much with it's quite high capacitance, and so can totally change the behaviour of a curcuit.