PC oscilloscpoe or a regular one? - Page 1
Forum section: electronics / testgear

author: Ymen
author_rank: Newbie
timestamp: May 09, 2015, 08:09:02 pm
content: hi all,I'm new to Electronic world and I'm currently playing with arduino stuffs. I just want to have a oscilloscope to investigate how things work like wireless transmission or sensor data and i found out that there are some pc based oscilloscope which are like 10 times cheaper then even the lowest end regular one and I'm just a poor youngster who only have like a hundred USD a month including lunchWhats is the pros and cons of a pc one?p.s. sorry for the Chinglish

author: Howardlong
author_rank: Super Contributor
timestamp: May 09, 2015, 10:32:36 pm
content: Any oscilloscope is better than no oscilloscope at all, but depending on what you want to achieve, a second hand CRO (old fashioned CRT oscilloscope) may well be more useful than a new basement priced toy.What oscilloscopes did you have your eye on?

author: pascal_sweden
author_rank: Super Contributor
timestamp: May 09, 2015, 10:48:49 pm
content: STAND-ALONE SCOPEThe cheapest 4-channel stand-alone oscilloscope currently available on the market is the Rigol DS1054Z. This scope has been crowned as the "most bang for buck" scope.There is a big community of Rigol DS1000Z users here on this forum, and everybody is very happy with the scope. Dave did a nice review summary video about this scope:You can upgrade this 50MHz scope to a fully-blown 100MHz scope with decoding options (SPI, I2C, SERIAL, etc.).PC SCOPEInteresting PC oscilloscope options to look at (with lots of extra's):Analog Discovery: (Students in the US can get a very big discount)http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,842,1018&Prod=ANALOG-DISCOVERY&CFID=10093707&CFTOKEN=5d3d9fa567ae95f0-4B9DE2B1-5056-0201-02843C2CF992CEC6Red Pitaya: (Open Source, new measurement modules coming up all the time)http://redpitaya.com/POCKET SCOPEInteresting pocket oscilloscope to look at: JYE Tech DSO112 (For low frequency measurements)http://www.jyetech.com/Products/LcdScope/e112.phpThis is a 50 USD pocket oscilloscope with color display and touch panel.The fact that it runs on a battery makes it an isolated scope, so you can do floating measurements that are not referenced to ground. The bandwidth is limited to 2 MHz, but this might be enough for some of your Arduino projects. Most people will consider it as a toy for their applications. But it can have its purpose for hobbyists doing Arduino stuff.NEED FOR DIFFERENTIAL PROBEIf you are a beginner, you should be aware that most oscilloscopes don't have floating inputs. Or in other words, most scopes don't have an isolated front-end. This means that you can only measure signals referenced to ground, and you can not connect the ground clip of your scope probe to anything else than ground in your circuit. If you do so, you generate a short, and this can be dangerous depending on what you are trying to measure. When you are measuring low voltages it will not be a big problem, but when measuring high voltages, your probe can explode.If you want to make measurements that are not referenced to ground, you can go for a differential probe. The cheapest differential probes for low-voltage measurements start at 150-180 USD.Recommendation on differential probe for low-voltage measurements: Pintek DP-30HShttp://www.pintek.com.tw/files/pintek/DP-30HS-40LV-DM-frond.jpgVoltage: 65V (Low voltage), Bandwidth: 30MHz (Limited BW), Sensitivity: 1mVrms (Very high sensitivity)Note that Pintek is working on a 100MHz differential probe for low-voltage measurements directed towards hobbyists. With this differential probe, you will be able to turn your 4-channel 100 MHz scope into a fully-blown isolated scope.

author: MarkL
author_rank: Unknown
timestamp: May 09, 2015, 11:12:07 pm
content: Quote from: pascal_sweden on May 09, 2015, 10:48:49 pmNo, not everyone is "very happy". I sent mine back due to the intolerable number of hardware and software bugs in it.Nevertheless, it is very popular and I wouldn't dispute bang for buck, *if* you want to put up with its faults.

author: artag
author_rank: Super Contributor
timestamp: May 09, 2015, 11:25:10 pm
content: If you want to explore analog signals, use an analog scope. Really good digitals are just about making a usable job of it now. They have tons of amazingly useful features, but they still suck for visualising real world data.Get yourself a good quality old scope like a Tek 465 (or even a real old cheap thing) and learn what signals look like and how measurement equipment distorts it. Don't spend much money. After a year or so, when you know what sort of problems you want to solve and maybe have a bit more cash, get something that does what you need. It might be the latest feature-filled chinese job, or a 10-20 year old high quality classic, but it'll solve the problems you want to solve, not just look good in a sales brochure.Don't use an oscilloscope for digital data. Use it to find out if the digital signals are valid, but analyse them using a cheap USB capture device. It's far more suitable for debugging I2C, SPI etc. than an oscilloscope, because the oscilloscope manufacturers can't keep up with the analysis software. A £10 capture device and Sigrok will be far more useful (or a £100 device from Saleae if you enjoy nicely made hardware and mostly polished software).

author: pascal_sweden
author_rank: Super Contributor
timestamp: May 09, 2015, 11:34:57 pm
content: Quote from: MarkL on May 09, 2015, 11:12:07 pmWhat did you get instead?Can you elaborate (very short) what the show-stopper issues were?The community here should come up with a structured table or matrix to collect all reported problems, categorize them, and keep a high-level overview of the playing issues in a table/matrix. Right now lot's of small things are reported, and then once in a while some bigger issues are reported. This information is spread out over the forum, and it is difficult to keep a high-level overview of the playing issues. The table/matrix would solve this, and would avoid that people have to scroll through hundreds of individual postings to get an idea about the playing issues. Ideally there should be 1 table/matrix for each popular scope. We could start with the DS1054Z table/matrix.

author: MarkL
author_rank: Unknown
timestamp: May 09, 2015, 11:55:26 pm
content: Quote from: pascal_sweden on May 09, 2015, 11:34:57 pmNothing. It was to augment what I already had. I thought for US$399 I had nothing to lose, so I thought I'd try it.QuoteMy major issues were the sample clock problem (now improved to the point were it doesn't affect much), problems with downloading waveforms, no documentation for stored waveform formats, and inability to install older versions (ludicrous).In addition, Rigol customer support was severely lacking in responsiveness. That was the final factor. I received no useful help by the time my 30-day return window came around, so back it went.QuoteHave you read this thread?:https://www.eevblog.com/forum/testgear/rigol-ds1000z-series-(ds1054z-ds1074z-ds1104z-and-s-models)-bugswish-list/I don't know if anyone has taken point on feeding these bugs to Rigol. I don't track it anymore.

author: Ymen
author_rank: Newbie
timestamp: May 10, 2015, 12:00:57 am
content: Quote from: Howardlong on May 09, 2015, 10:32:36 pmI'm looking at Hantek6052BE (http://www.hantek.com/en/ProductDetail_2_31.html)I live very close to china so I use Taobao instead of eBay which make my shipment fee almost $0(maybe up to USD10 if heavy)I have found some second hand Hitachi V1560 CRO at the similar priceDo those CRO have data logging function like the digital does? I've learn some programming so maybe i can do some stuff with those data

author: daybyter
author_rank: Frequent Contributor
timestamp: May 10, 2015, 03:22:14 am
content: The 6052 is not compatible with the 6022, so none of those nice 6022 software projects will work with it? (RichardK, rscope)

author: Ymen
author_rank: Newbie
timestamp: May 10, 2015, 04:32:50 am
content: Quote from: daybyter on May 10, 2015, 03:22:14 amyou mean there is software project for 6022?Couldn't find one. (find something call OpenHantek but seems not specific to 6022http://www.openhantek.org/)

author: Ymen
author_rank: Newbie
timestamp: May 10, 2015, 04:52:17 am
content: Quote from: blueskull on May 10, 2015, 04:35:51 amWell I mean FM boardcasting when I say wireless so maybe I don't need to play with GHz frequency.And I'v eseen Dave review on OWON SDS9302 ()so not really a fan of OWON,

author: Howardlong
author_rank: Super Contributor
timestamp: May 10, 2015, 08:15:23 am
content: An oscilloscope is far from the best tool for dealing with RF signals. I could mention a spectrum analyser but that would probably be out of budget. The alternative is an SDR, even those cheap RTL based devices will allow you to see your signals and harmonics. They are useless for measuring absolute power, but there are other options for that, your average SWR meter will do that for you.

author: pascal_sweden
author_rank: Super Contributor
timestamp: May 10, 2015, 08:18:15 am
content: I just learned about the HackRF One yesterday.That seems an interesting gadget to look atIt can both receive and transmit at those frequencies.Pity that power measurements are not accurate, otherwise this would beat any spectrum analyzer.

author: Ymen
author_rank: Newbie
timestamp: May 10, 2015, 08:28:04 am
content: Quote from: Howardlong on May 10, 2015, 08:15:23 amI suddenly come up some thought with measuring RF signals, I've once hack a analog TV receiving stick (for computer) to receive any RF signal (not sensitive but still do the trick)Maybe I can use that?

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: May 10, 2015, 09:43:24 am
content: Quote from: Ymen on May 09, 2015, 08:09:02 pmForget about PC scopes. They all suck as general purpose scopes. The cheap ones come with crap software or very poor specs, and the good ones are made for special purposes (i.e. digitizers for automated test systems) and are even more expensive than a good standalone scope.If you're short on cash then either get a decent low cost scope (like the Rigol DS1054z that has been mentioned before), or try to find a cheap ($70 or less!) or even free old and working(!) analog scope that will do the basics, and then save up for a proper digital scope.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: May 10, 2015, 10:40:49 am
content: Quote from: artag on May 09, 2015, 11:25:10 pmYou're joking, right? If you think that DSOs "suck for visualising real world data" then you've apparently never used a proper DSO, because that's just a load of tosh.Even 10+ years ago there already were many DSOs with very fast waveform update rates, and there are even more of them today, even in the low end sector. In fact, you will have a hard time to finding any new standalone scope with low waveform rates.As to "visualising real world data", there's hardly anything worse than an analog scope where all you get is the waveform on the screen. With a good DSO I also get all signal parameters, statistics, the individual frequency components the signal is made from, and a wide range of other information. Just finding a rare glitch is pretty difficult on an analog scope, unless you find one of the old analog storage scope boat anchors with s storage tube that is still working after all these years (and even then you're not even close to what even a low end scope can do).Your statement was probably true up to the late '80s but since then a lot has changed.BTW, all signals are analog, even those representing digital information.QuoteI agree that serial decode on low end DSOs often sucks, and a cheap £10 USB capture device is often a better alternative, especially if one is cash strapped as the OP. But in general, scope manufacturers do keep up pretty well with analysis software. Saleae is fine for I2C, SPI, JTAG and similar slow and common protocols, but good luck trying to analyze faster signals like DDR3/DDR4, USB3.x, DisplayPort, 10G Ethernet, SAS/SATA and such on one of these devices. Guess what the standard device is in many labs for these standards? Exactly, a DSO.For the OP, the best option I see is to save a bit and get a decent low end scope like the often mentioned DS1054z, especially if the entry into EE is a bit more serious. An analog scope can be fine as a starter but only if it's free or really cheap and fully working, as one of the worst thing for a beginner is to sink money in a tool that quickly turns into a project in itself.

author: VK5RC
author_rank: Unknown
timestamp: May 10, 2015, 11:35:59 am
content: Re Analogue vs Digital, the ability to capture "one shot" problems easily and well in a DSO and then be able to explore around the event is a huge plus, was very helpful recently troubleshooting a linear PSU (with lots of OV OC protection circuits) with a switch on problem. It was an 8uS OV spike, arrrggghhh.

author: Fungus
author_rank: Super Contributor
timestamp: May 10, 2015, 02:02:48 pm
content: Quote from: Ymen on May 09, 2015, 08:09:02 pmThis question is asked aLOThere and the answer is always the same: There arenogood PC scopes which cost less than a 'regular' one. If you buy a cheap PC scope, you will almost certainly regret it.Sorry.