Choosing USB Scope or standalone - Page 1
Forum section: electronics / testgear

author: Gadjet
author_rank: Contributor
timestamp: December 30, 2018, 10:52:21 am
content: Hi,I'm looking at buying my own general purpose cheap scope, I will mainly be using it for working with Arduinos etc. nothing really demanding.I only want to spend less than £200 and was initially looking at an Hantek DSO5072P but then I noticed the Hantek 6022BE or the OWON VDS1022.I realise the first thing people may say is spend more money as these budget scopes are crap but I just want something cheap, if I need something more I can borrow the lecroy from work.My main question is about the PC interface on the USB scopes, I plan to attach it to an un-used windows10 10 inch tablet I have with some sort of 3D printed bracket so I will effectively have a standalone scope for less than buying the standalone one (forgetting the price I paid for the tablet)Has anyone used the PC SW on a touch screen, does it lend itself to working with a touch screen?Any feedback would be welcomed.Regards,Philwww.gadjet.co.uk

author: coromonadalix
author_rank: Super Contributor
timestamp: December 30, 2018, 12:57:51 pm
content: Hantek usb scope doesnt have big reputations, the software seems to be the culpit, you have to be usb isolated too just in case.Same isolation principle for an bench oscilloscope too (isolation transformer) and you're ready to go.You have many good new / used bench scopes, and now they are very slim unless you go for the old physical size of 5 -10 years ago, but you can snatch very good deals ??Personally i dont want to depend of an usb scope, you need computer ... softwares, and physically you may take around the same place on a desk ??I use an "old" Tektronix TDS1012C with an voltage autorange and i loooooooooove it. Doesn't take much place ...For the Hantek or some other brand, you have some models known to be "cough cough" hackable / be unlocked to give more bandwith ...

author: tggzzz
author_rank: Super Contributor
timestamp: December 30, 2018, 01:21:55 pm
content: Quote from: Gadjet on December 30, 2018, 10:52:21 amThere are many threads on this subject.You might as well start by understanding the points inhttps://www.eevblog.com/forum/beginners/best-oscilloscope-for-beginer/Given that you appear to want to use the scope with something that is controlling mains supplies, you should factor failure modes into your decision. You can findsomesafety references athttps://entertaininghacks.wordpress.com/library-2/scope-probe-reference-material/and in other threads on this forum. Be aware of the Dunning-Kruger syndrome!

author: wraper
author_rank: Unknown
timestamp: December 30, 2018, 01:26:25 pm
content: Cheap USB oscilloscopes suck but decent ones usually cost even more than affordable standalone scopes with similar spec. Also if you do something wrong, there is a good chance destroying your computer together with a scope.

author: wraper
author_rank: Unknown
timestamp: December 30, 2018, 01:31:38 pm
content: Also DSO5072P is old model and was pretty poor even when was new. Adding $100 will buy a way better scope which will satisfy your needs for much longer time.https://www.amazon.com/Siglent-Technologies-SDS1202X-Oscilloscope-Channels/dp/B06XZML6RD/ref=sr_1_3?ie=UTF8&qid=1546176490&sr=8-3&keywords=SDS1202X-E

author: Gyro
author_rank: Super Contributor
timestamp: December 30, 2018, 01:34:47 pm
content: For the two USB scopes you mention, there are long threads covering them in detail. I agree with coromonadalix, the Hantek one is far too limited, too little H/W, too much dependence on PC performance. The Owon ('i' version) is a well behaved USB isolated choice in the sub £100 bracket.I'm not aware of any of the softwares supporting Windows 10 touch screen operation (unless Win10 does some UI cleverness).In the sub £200 range, there are probably other options but I'm not familiar enough with them to comment.

author: Gadjet
author_rank: Contributor
timestamp: December 30, 2018, 01:43:55 pm
content: Unfortunately here in the UK the £ price is the same as the $ price effectively making the SDS1202X-E double the cost of the Hantek so not an option.

author: Gadjet
author_rank: Contributor
timestamp: December 30, 2018, 01:59:22 pm
content: Quote from: tggzzz on December 30, 2018, 01:21:55 pmI googled the syndrome, put a smile on my face, I dabble in many many different hobbies and am guilty of the syndrome in more than a few. I never stop learning.Thanks for the other info.

author: tggzzz
author_rank: Super Contributor
timestamp: December 30, 2018, 03:26:27 pm
content: Quote from: Gadjet on December 30, 2018, 01:59:22 pmYou're welcome, join the clubs both EEVBlog and being inexpertI didn't have you in mind w.r.t. that syndrome; I was thinking of some of the posters on this forum. Sifting the information from the morass of data is, as you know, a key modern skill.

author: nigelwright7557
author_rank: Frequent Contributor
timestamp: December 30, 2018, 03:48:24 pm
content: You can pick up USB scopes on ebay for a few pounds.Nothing like a big pc screen for showing waveforms.

author: DDunfield
author_rank: Regular Contributor
timestamp: December 30, 2018, 04:57:33 pm
content: On the subject of USB .vs. bench, If:- It's your primary scope- You are going to use it frequently- You have space for it on the bench without it being in your way (a shelf not too high above the bench works great)then I'd say "Bench scope" hands down. Nothing beats having real knobs and switches!Most low-cost USB scopes suck. I've tried a few of the low-cost streaming scopes like the Hantek and the Sainsmart, and they were terrible. Unreliable triggering, nearly impossible to do good single-shot captures, whole chunks of the waveform "just missing". The VDS1022seems a completely different animal, as it appears to be an actual scope, with triggering and buffering handled in hardware. So far it looks quite promising (disclaimer I've only had mine for a week). The VDS seems to be a good combination of "actually works", and less expensive than bench scopes. There are other good/better USB scopes available, but they'll be as expensive as a decent bench scope which for most will be a better choice.Other things to consider:Working on Arduino, you probably don't need super-fast ... all the tricky fast stuff will be inside the Arduino. Possible exception is if you are planning to run super-fast serial interfaces and will be designing the communications hardware .. but for most general Arduino users, you don't need fast. Fast is nice, but also the most expensive "feature" of a scope and may not be the best place to put your budget. The 25Mhz of the VDS1022 is probably ok, and 50/100 of a Rigol or similar is likely more than enough.Two channels is 100x better than 1 channel (maybe 1000x) - with only one channel it's really hard to compare two signals in relation to each other. Four channels is 10 times better than two channels, in other words, really nice to have, but not as essential as minimum of two channels. Keep in mind that a 2-channel scope with external trigger can effectively "look at" three signals.Deep memory is nice, but you normally don't need "megs", especially if the scope does not have built in protocol decoders. Built in protocol decoders are nice, especially coupled with deep memory where you can capture a long stream and scroll through it. But these will add to your cost and are only useful if that is the kind of thing you are likely to be doing.Consider adding one of the 8-bit logic analyzers available on Ebay for the cost of a sandwich. With suitable software (Sigrok) these will provide you with deep memory and protocol decoders for digital signals very inexpensively.If you plan to do processing of the signal on a PC, consider how tough it will be to get the data over. I don't know about the Siglent, but the Rigol is amazingly slow at writing waveform data to USB. Using their "ultrascope" software to move it over the LAN is considerably faster, but still longer than I'd like (but it can be a lot of data - up to 24M samples). With the VDS1022, it is very fast to save the waveform data as it's already on the PC... It's also only max 10k samples.DavePS: I'll dig out my Win8 tablet and install the VDS software on it later today and let you know how well it works with touch. There's also "HSCOPE" for android which supports a number of these scopes (the author participates in these forums - I've just started to look at it.

author: Gadjet
author_rank: Contributor
timestamp: December 30, 2018, 07:58:34 pm
content: Quote from: DDunfield on December 30, 2018, 04:57:33 pmThanks Dave that's probably one of the best most helpful answers I've had on any forum so far.I am leaning towards the bench scope as it does seem to be a better spec option but I'm really tempted to create my own 10" scope with the VDS1022 attached to the back of a now un-used windows10 tablet and if the VDS1022 does most of the heavy lifting in hardware then it should work OK and I can even plug it into my desktop PC when a bigger screen is required and now you say there is Android SW as well ..... it must be Christmas!!P.S. I do already have a £10 logic analyser and it's really good for decoding stuff

author: DDunfield
author_rank: Regular Contributor
timestamp: December 30, 2018, 08:31:32 pm
content: Quote from: Gadjet on December 30, 2018, 07:58:34 pmI just installed and tested the VDS1022I on a 10" Windows8 tablet. It worked surprisingly well, easier to manipulate with just the touch screen than I thought it would be.Really, the only issue is certain UI elements are smallish, not too hard to manipulate with the mouse, but a bit trickier with just touch.Most if not all of these are also available through the menu, which is quite easy to operate touch - I'm talking about the on-screen shortcuts, for example, you can "click" the vertical voltage/div display to directly bring up the adjustment menu.Probably the only ones that might "annoy" you is adjusting vertical position, triggering and horizontal position by dragging little "triangle" markers at the edge of the grid display. Since my finger is bigger than the markers, it's hard to see when I am on it - but I'm sure you would get used to it with a bit of practice ... as noted above, I found it easier than I thought it would be.BUT!!! - still nowhere near as nice to operate as a bench scope!You can get a feel for it before you buy the scope if you like, because the OWON software can be downloaded from their site, and will install and run without the scope. You obviously can't capture any waveforms, but you can move the above mentioned points and access the menus, on-screen shortcuts and other settings, which might be a worthwhile exercise.Note that I had issues with the scope disconnecting after installing the latest (1.0.30) software from OWONs site, but no problems after clearing out and installing 1.0.29 which came with the scope. You can see my adventure towards the end of the "OWON VDS1022I Quick Teardown" thread here in this forum. I suspect it was related to using the "new" driver posted separately on OWONs site, the working install just used the driver which gets installed with the software (you still have to manually "update driver" to install it since the auto-install option via the software doesn't work).A couple other considerations using a tablet.The scope is powered via USB and is supplied with a "dual head" cable able to suck power from two USB ports. I measure between 350ma and 450ma of current draw, depending on what it is doing which is just within the 500ma spec for a single port. I tested it and it works fine with a standard single-head cable (That's what I used with my tablet as it does not have two USBs close enough together), but some tablet & laptop ports are not up to the full 500ma and you may need the special cable.Processor wise it doesn't need much - my tablet is an AMD C-50 CPU (fairly low performance dual-core), and last night I tested it on an single-core Intel Atom (N270) netbook and it also ran fine.Regards,Dave

author: Gadjet
author_rank: Contributor
timestamp: December 30, 2018, 10:18:36 pm
content: Dave,Thanks for taking the time to try out the SW on a tablet, it's good to know it should be fairly usable.The power issue is a good spot, I can test the current capacity of the USB port on the tablet before I take the plunge .... if I decide to go the USB route.I will continue to have a read of the many posts on the forum relating to the Hantek and OWON scopes and have a bit of a think on which direction I want to go and I will download the software to have a play with as well.Again thanks for your help.

author: jack-daniels
author_rank: Contributor
timestamp: December 30, 2018, 10:38:56 pm
content: I know what you said in your OP about price, but seriously look at this,https://www.eevblog.com/forum/buysellwanted/fs-(uk)-siglent-sds1104x-e/That's a lot of scope for the money with 2 years guarantee left, and you won't go wrong dealing with Toploser.I would have had it but I've just bought one from Welectron. I'm a total newbie to electronics but some research tells me this is the best bang forbuckquid scope by a long way.I don't think I'll ever outgrow it.

author: Gadjet
author_rank: Contributor
timestamp: December 30, 2018, 11:38:35 pm
content: Thanks for letting me know but it's just after Christmas and I've just spent £150 on a pair of new headphonesso there's no way in hell I can go above £200unless I sell something and although an oscilloscope is something I always wanted to buy, I usually borrow one from work so I can't really justify spending much more, just something cheap and cheerful, I'm now tempted to buy a USB scope as it will more than cover 99% of my needs and I have a Win10 tablet I can use with it.

author: Gyro
author_rank: Super Contributor
timestamp: December 31, 2018, 10:33:29 am
content: Just a quick reminder - If you go for the Owon, do make sure it's the VDS1022(I) USB isolated version. The galvanic isolation will save your PC someday, or even your tablet if it happens to be on charge.The cost difference is pretty minimal.

author: Fungus
author_rank: Super Contributor
timestamp: December 31, 2018, 10:57:40 am
content: Just want to add:If it's mostly for "Arduino" then get four channels. Two channels isn't enough.

author: bd139
author_rank: Super Contributor
timestamp: December 31, 2018, 11:32:25 am
content: Look out for Tektronix TDS 210 (60MHz) / 220 (100MHz). They come up cheap on ebay occasionally (£60-150 - paid £60 for mine!). Old but perfectly good. Memory depth is a bit poo but that doesn't matter much really for general purpose use. They're small, light, silent, functional enough for the average user and are dead simple to use and repair if they go wonky. Add some £7 cheap probes and you're in business. If you are doing Arduino stuff, it's worth snagging a cheap aliexpress logic analyser as well.Teardown / repair of mine:https://www.eevblog.com/forum/testgear/tektronix-tds210-teardown-and-bnc-replacement/

author: Gadjet
author_rank: Contributor
timestamp: December 31, 2018, 11:34:39 am
content: FYIJust came across this on youtube, OWON VDS1022I on a touch screen tablet.https://youtu.be/di-UndlTnac

author: DDunfield
author_rank: Regular Contributor
timestamp: December 31, 2018, 12:35:49 pm
content: Quote from: Gyro on December 31, 2018, 10:33:29 am+1 - definitely worth getting the 'I' version. It is possible to upgrade the non-I to Isolated, but in addition to voiding any warranty, I don't think it actually saves you much over just getting the 'I' in the first place.Quote from: Fungus on December 31, 2018, 10:57:40 amWhile I agree that 4 channels is really nice, not sure I agree 100% in this case, as I don't think he can stay within his stated budget and get a decent 4-channel scope.Most of the cases where you want 4 channels with Arduino are "digital" in nature (SPI etc.) and he did say he has one of the Ebay logic analyzers which should cover that off reasonably well.Scope (with Arduino) will be useful for looking at analog in/outs, debugging drive conflicts, checking signal integrity etc. and you can do that on a line by line basis, and leave decoding etc. to the LA. As stated in previous post, I think two channels is a MUST so that you can see one signal in relation to another, but in this case 4 may be a luxury.Quote from: bd139 on December 31, 2018, 11:32:25 am+1 - I still have/use/like my TDS210. There are things I like about it better than the Rigol (UI is faster, Separate channel controls, encoders are faster, cursor measurements don't cover part of waveform).But there are a couple things to consider:The record sample depth is 2.5K which in all honesty, I find to be quite adequate for most purposes (and much better than the 512 samples of my Fluke) ... but I do "run up against the stop" sometimes and captures get pretty grainy when you have to zoom excessively. The 5K of the VDS is still small, but will be a big improvement vs the TDS. OTOH, he has an LA which will cover off most cases where you have to capture big and see small which are usually with digital signals.Unless you are lucky enough to snag one with the TDS2CM communications module installed, it will be basically impossible to print or move capture data to a PC. Used comm boards often go for more than the scope and will quickly make total cost not worth it. If you happen to get one, it will give you RS-232 (serial), Centronics parallel and GPIB .. not always the best way to talk to modern PCs.If you want to do things like FFT and other advanced measurements, that is another unobtainium option module (TDS2MM).Still a great basic "turn the dials and see" scope! If you can find working one at a good price, you can't go wrong.Dave

author: bd139
author_rank: Super Contributor
timestamp: December 31, 2018, 01:24:06 pm
content: Yep. I actually sold my DS1054Z and kept the TDS210 and kept the left over cash. It was a good tradeoff. WRT screenshots I am not blessed with the TDS2MM/CM so I just take a photo with my phone. Low tech but it works and was exactly what I was doing with an analogue scope.

author: Fungus
author_rank: Super Contributor
timestamp: January 03, 2019, 05:46:09 am
content: Quote from: DDunfield on December 31, 2018, 12:35:49 pmI disagree. I don't use 4 channels for SPI decoding, I use 4 channels for debugging, eg. toggle a pin in an interrupt handler so you can see it's happening after a signal is received, etc.Those logic analyzers are good for decoding data but they don't update in real time for watching signals.

author: Gyro
author_rank: Super Contributor
timestamp: January 03, 2019, 12:24:58 pm
content: Actually, I believe Saleae have recently added some form of real-time display to their S/W. I've no idea what products support it, particularly any of the clones. To stay honest, it would be really nice if the same feature could be added to Sigrok.

author: Fungus
author_rank: Super Contributor
timestamp: January 03, 2019, 12:38:55 pm
content: Quote from: Gyro on January 03, 2019, 12:24:58 pmIt would be absolutely awesome to have an eight channel digital display with triggering. I really don't know why they don't/can't do it, the hardware is obviously capable.(obviously there'd be a lot of jitter on the trigger from the low sample rate, but still... it's $6 and 8 channels)

author: LapTop006
author_rank: Unknown
timestamp: January 03, 2019, 02:13:26 pm
content: Quote from: DDunfield on December 31, 2018, 12:35:49 pmHere's a case that came up recently where I used all four analog channels of my scope.Ethernet PHY chip isn't working, I know it might be power related (I'm overdrawing from the nominal spec of a rail, but pretty sure it's ok), so I put all four rails for this chip on the scope while running through tests. If they weren't rock solid I would probably have wanted to add some additional signals to better time-correlate the drops, but in this case it wasn't power.Now sure a basic Arduino circuit (let alone single chip) probably doesn't have even two rails, but you do find uses for those channels very quickly, and sure you can often get away without them, but darned if they don't make things quicker & easier.

author: Fungus
author_rank: Super Contributor
timestamp: January 03, 2019, 03:09:27 pm
content: Quote from: LapTop006 on January 03, 2019, 02:13:26 pmYep. If you have them, youwilluse them.If you've never had a four channel 'scope then two channels might not look like a limitation. If you've had four channels, though, it does. Two channels would be a big step backwards for me.One other thing to consider if you really have no money is one of thoseDSO Quadthings. The user interface is awful but they're small, they really work, and they have four channels.I used one for about a year before I got my DS1054Z and I still take it to Arduino club (where small size+battery power is a big deal). The difference between a DSO Quad and no oscilloscope at all ishuge.

author: DDunfield
author_rank: Regular Contributor
timestamp: January 03, 2019, 07:42:30 pm
content: Quote from: LapTop006 on January 03, 2019, 02:13:26 pmI'm not saying "don't get a 4 channel scope" - I have a 1054Z and use it frequently. There are times when it's really handy. But I still often use my other 2-channel scopes, and my 1-channel scopemeter --- I don't recall ever being out and about with one of my other scopes, and not having the 1054Z threw up my hands saying "Can't do without it" - that's not to say I haven't "wished it were here".In all fairness, in the testing described above could have been done with a 2-channel scope by repeating it, and measuring two pairs. It could even have been done with a 1 channel scope by repeating it 4 times, once to look at each rail. But I completely agree that being able to see all four rails at once is "just easier", especially if you need to do this kind of test frequently. Although ... free-running and "just looking" may not be the best way to find small rail glitches... I might end up looking at them individually anyway.The reason for my previous statements is that I was trying to offer information applicable to the stated budget. I'm just not aware of any decent 4-channel scopes which would fit (anyone?).Quote from: Fungus on January 03, 2019, 03:09:27 pmI've considered the DSO-Quad for the portability, but so far avoided it as much of the feedback I've seen from people used to traditional scopes is pretty bad - which leads to a question since you are familiar with both .. Would you prefer to have the DSO Quad or a decent 2-channel bench DSO if it were the only scope on your bench on a daily basis?Dave

author: DDunfield
author_rank: Regular Contributor
timestamp: January 03, 2019, 08:11:03 pm
content: Quote from: Fungus on January 03, 2019, 05:46:09 amYep.. 4 channel is nice for this You can see 3 things plus your toggle. With a 2-channel scope, I tie the "toggle" pin to external interrupt, then I can look at 2 other things. If I need to see more, I use the LA and have to start a new capture every time I want to see what is going on.They wouldn't actually have to add much to the LA to accommodate an almost real-time update (like DSO above a certain speed):1) Let you set sample rate and buffer depth to accommodate short/quick captures.2) Provide an option to automatically re-arm the trigger following a capture.3) Leave the last display on-screen (and not cover it up with a "Waiting" window) while you are waiting for the next capture to complete.Then... every time you toggle a pin, you would get a picture of up to 7 (or 15, 23.. depending on the LA size) other signals activity around it (as defined by your sample rate, buffer size and pre-trigger size).Funny how software guys want different features in their tools!Dave

author: Fungus
author_rank: Super Contributor
timestamp: January 03, 2019, 08:44:29 pm
content: Quote from: DDunfield on January 03, 2019, 07:42:30 pmIfmostof my work was "Arduino" (ie. 5V signals, limited to 16MHz clock) then I'd probably choose the DSO Quad. Being able to see four signals at once would easily compensate the lack of twisty knobs. The user interface would mostly be just changing the time base and looking at frequencies, not too demanding on the Quad's buttons.(plus I'd have one of those $6 logic analyzers for protocol decoding/looking at longer sequences of pulses - the DSO Quad doesn't do that).For other types of work, eg. If you're constantly switching between horizontal/vertical controls, the DSO Quad is a pain in the ass. Plus the bandwidth is really limited, maybe 20MHz at best.

author: Gyro
author_rank: Super Contributor
timestamp: January 03, 2019, 08:56:01 pm
content: One thing that people tend to have forgotten about these days is the external trigger input. This is usually available on 2-channel scopes, but is absent from lower end 4-channel models, eg. the Rigol ds1054z as far as I can see.In analogue scope days, the Tek475 (and probably many others) for instance, have a trigger view button to help with setting trigger level. Granted, it's not so convenient in modern 2-channel DSOs, as you need to scope your 'strobe' signal first to confirm its integrity but it does allow you to use the external trigger as a pseudo 3rd input channel in a lot of logic situations.

author: Fungus
author_rank: Super Contributor
timestamp: January 03, 2019, 09:23:11 pm
content: Quote from: Gyro on January 03, 2019, 08:56:01 pmThe idea is to use one of the four channels for triggering.Quote from: Gyro on January 03, 2019, 08:56:01 pmThe low end Keysight can display trigger-in on screen and work with it like an analog trace, it's really a 2.5 channel oscilloscope. I don't know of any other low-end DSO that can display the trigger signal on screen though.

author: Gyro
author_rank: Super Contributor
timestamp: January 03, 2019, 09:46:19 pm
content: QuoteI know that.I was merely pointing out a somewhat neglected method of achieving the most from a 2-channel scope. I didn't say that it was a replacement for a 4-channel scope.Quote... and I did point out that it was less convenient because you needed to scope the 'strobe' signal to be used for triggering, to ensure it's integrity first.

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: January 05, 2019, 12:23:28 pm
content: Save up and buy a Rigol DS1054Z, I bought an open-box one from Tequipmet.net for <$300 after eevBlog discount. It's possible to 'upgrade' this to a DS1104Z with all options very easily. When I bought mine, all options were included with the exception of the bandwidth upgrade.This is an awesome 4-channel scope that will do 99% of what most people need, I use mine every day.I just checked and you can get the same deal I did right now, possibly better.

author: Gadjet
author_rank: Contributor
timestamp: January 06, 2019, 08:47:48 pm
content: Quote from: Gandalf_Sr on January 05, 2019, 12:23:28 pmThe thing is, it's not that I don't have the funds it's just that I can't justify the spend on something that won't get a lot of use and here in the UK things tend to cost a lot more than in the states anyway.

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: January 07, 2019, 03:59:45 pm
content: I know life is harder in the UK (I lived in the UK until I was 40) than the USA and you don't have as much disposable income but, for around $250 for a nearly new DS1054Z you can't go wrong, even if you have to pay 20% VAT.USB-based scopes are a waste of money IMHO.There's apparently an old Czech expression.. "we're too poor to buy cheap stuff".

author: Gadjet
author_rank: Contributor
timestamp: January 12, 2019, 09:25:04 pm
content: Thanks for all the advice, I went for the Hantek Dso5072p, I bought two, one for a friend at work, and got a discount so paid £188 ea.

author: Rohde_TestWalker
author_rank: Newbie
timestamp: February 20, 2019, 06:21:54 pm
content: One thing you should consider when deciding whether to purchase a USB scope or a standalone or benchtop scope is ease of use. We think benchtop scopes are easier to use, and that ease of use translates into higher productivity. That may not be a big deal for a hobbyist, but for a professional engineer, having a scope that's easier to use, means that you'll be more productive, and that, in turn, helps shorten development cycles and lowers development costs.Of course, that doesn't mean that engineers should shun USB scopes. They're certainly the right choice for some applications, especially those that don't require a lot of user interface, such as automatic test equipment applications.

author: Andreax1985
author_rank: Regular Contributor
timestamp: February 21, 2019, 07:05:12 am
content: I do not feel comfortable hooking up my laptop to a usb scope. I work with audio amplifiers and do not want to risk frying my notebook in case I do something wrong.

author: Gyro
author_rank: Super Contributor
timestamp: February 21, 2019, 12:58:32 pm
content: It depends whether you use a USB isolated one or not but yes, it is bad to accidentally pass ground current through any sort of test equipment.

author: bd139
author_rank: Super Contributor
timestamp: February 21, 2019, 01:07:03 pm
content: Yeah. A ground can shift some amps. Nice picture of a cock up I did recently by dropping a probe on a power supply after forgetting to put a locating sleve on it. If this was a poorly isolated USB scope I would have lost the PC it was plugged into.Made one hell of a bang that did!