It's that time again, considering buying a digital 'scope, recommendations? - Page 1
Forum section: electronics / testgear

author: CJay
author_rank: Super Contributor
timestamp: August 01, 2019, 11:16:57 am
content: Desk space is at a premium here and my analogue 'scopes are getting long in the tooth so, time to consider a digital 'scope again.Needless to say, the budget is tight but...I will be working on HF Radios, audio gear and microprocessor/microcontroller gear, I think 100MHz bandwidth would be sufficient for my needs but of course higher is nicer.I'd like serial decoding for I2C and SPI and of course, again, more is nice.Logic analysis would come in handy, lots of legacy stuff here so 16 channels would be good.2 analogue channels will suffice but if I can have more, why not, the need occasionally arises.So, what would you recommend?I'm open to suggestions for new and second hand gear, I'm not tied to the idea of LCD over CRT or vice-versa

author: Zucca
author_rank: Unknown
timestamp: August 01, 2019, 01:14:54 pm
content: Quote from: CJay on August 01, 2019, 11:16:57 amwhat's your budget? Or you want the best bang for the buck?I am TEA Keysight addicted, so I would be very biased in my suggestion.Maybe shoot a PM to TopLoser (UK too), he could have something under his desk for you.

author: bd139
author_rank: Super Contributor
timestamp: August 01, 2019, 01:42:20 pm
content: Has to be a the DS1054Z for that set of constraints if you ask me. Don't bother with getting the MSO version - just get a cheap Salea clone analyser off aliexpress. Rationale:1. All the other second hand digital scopes that are worth a look at go for nearly the same price and are pretty much circling the drain. You risk throwing the cash away and there's no service manual past FRU replacement for modern digital scopes.2. You can crack it to 100MHz trivially.3. It has 4 channels which is extremely handy for SPI protocol decoding, something which I end up doing quite a lot. You sacrifice one when you need an external trigger but that allows you to actually view the trigger signal, something missing from a lot of analogues.4. It's mature and most of the bugs have been worked out.5. The FFT isn't terrible as an HF spectrum analyser (see screen cap later)6. We have a proper legitimate and decent distributor here in the UK who are regulars and hamfests and have excellent support (Telonic:https://www.rigol-uk.co.uk/)7. Resale value is nearly the retail price so it's low risk.8. Has LXI and ethernet so you can actually use it over a LAN to compose new instruments with it.Usefulish FFT showing post first mixer products in an HF receiver (yes that one finally)Downsides are it's noisy (my most recent one is less noisy than the older one was) and the interface is a bit sluggish but it does the job pretty well and I'm not unhappy with it for the cash.Edit: just to add I've owned two over a period of 2017-current.

author: 001
author_rank: Super Contributor
timestamp: August 01, 2019, 01:52:20 pm
content: Quote from: bd139 on August 01, 2019, 01:42:20 pmWhy You had change two identical units for two years?

author: bd139
author_rank: Super Contributor
timestamp: August 01, 2019, 02:06:04 pm
content: There was nothing wrong with the units. My test gear requirements reduced so I didn't need one for a bit. Rather than it sitting there rotting, I sold it for £30 less than I paid for it thus reducing my TCO of that scope to £5/month (£30 for 6 months of service). All about the cash flowThings have ramped up a bit now so it's a permanent fixture.

author: BillB
author_rank: Unknown
timestamp: August 01, 2019, 03:57:47 pm
content: https://www.eevblog.com/forum/testgear/is-rigol-ds1054z-still-a-good-option-in-2019/

author: aristarchus
author_rank: Regular Contributor
timestamp: August 01, 2019, 03:59:22 pm
content: Same usage here as the OP needs, HF, microprocessor, etc.Advice: Get the DS1054Z, nowadays it is given with all options enabled from factory.As said, avoid the MSO, appart from you can do better with a Saleae LA, the MSO is not easily hackable (I know, I got DS1104ZPlus, and bought the RPL1116..).

author: Howardlong
author_rank: Super Contributor
timestamp: August 01, 2019, 04:12:47 pm
content: The MSOis hackable but not easily, I’m not sure what the current process is, but I think I had to install a serial header.

author: CJay
author_rank: Super Contributor
timestamp: August 01, 2019, 06:34:41 pm
content: Of course I want as much as possible for as little as possible so the DS1054Z is attractive as it's hackable and already comes with the serial decode options out of the box, has a pretty good reputation and has proven to be fairly reliable.I could, at a push, stretch to the DS1074Z Plus for the LA feature because bench space and convenience but am I reading it correctly?The probe set and licence is an extra £226 + VAT?If that's the case and it's not possible to either hack it and attach a 'standard' set of probes (I'm thinking re-purpose from elsewhere) then a USB connected standalone LA is a much better option (I've already got a couple of the dirt cheap Saleae clones)

author: Howardlong
author_rank: Super Contributor
timestamp: August 01, 2019, 07:02:12 pm
content: Regarding whether a USB LA like a Saleae is “better” than an MSO’s LA is a bit like comparing apples and oranges. It’s a case of horses for courses.You tend to use comprehensive real time trigger techniques with an MSO, whereas with a USB LA like a Saleae you use post processing analysis.Good luck with capturing a high speed SPI bus on the entry level Saleae for example.Personally speaking I much prefer the MSO approach, and that’s after using USB LAs for at a decade before I bought my first MSO.There are a few things that USB LAs can do that MSOs can’t, particularly around slightly more esoteric protocols like 1-wire. Some offer DIY scripting for your own protocols.If I had to choose one it would be an MSO, but better to have both!

author: Howardlong
author_rank: Super Contributor
timestamp: August 01, 2019, 07:04:04 pm
content: The MSO cable set for the MSO1000Z is active, with high speed comparators in the pod.

author: aristarchus
author_rank: Regular Contributor
timestamp: August 01, 2019, 07:26:34 pm
content: Quote from: CJay on August 01, 2019, 06:34:41 pmIf by "hack it" you mean to connect somthing of your own DIY, have a lookk at this, it is definitively not trivial->https://www.eevblog.com/forum/testgear/rpl1116-active-logic-probe-pod-for-1000z-series-teardown/msg2085451/#msg2085451For my usage, specifically I2S protocol, I do rely on the cheap dongles that you probably already got, the PC application for that cannot be matched by any MSO LA, but for more elaborate work, eg to hook up a FPGA with multiple signals application, then yes, the MSO LA is indeed better as it is proved such when I needed it.For firmware hacking, beware though, the MSO needs a process wich is not for the faint hearted.At least in mine which is a two year already, it required a soldering of a JTAG pinheader on the scope's board, downloading its resident firmware with a JTAG, compiling and running a modified rigup application extract the required keys and then generate the licenses. Info on that process is sparse and not easily to find. the plain DS process though is just using riglol and entering the generated lics.

author: nctnico
author_rank: Super Contributor
timestamp: August 01, 2019, 08:00:41 pm
content: We should have a sticky thread for the cheap scopes 'du jour'.https://www.eevblog.com/forum/testgear/is-rigol-ds1054z-still-a-good-option-in-2019/

author: Old Printer
author_rank: Frequent Contributor
timestamp: August 01, 2019, 08:47:16 pm
content: I bought the Siglent 1104X-E because I think it is a bit more current design than the Rigol 1054Z. It has 2 discrete ADCs to start with. SPI - I2c - UART included from the factory. $500 vs $350, I felt the extra $150 was worth it to have a more current design, but that is just my feeling. For an LA I use an Analog Discovery, mostly because it comes with so many other tools as well.

author: tautech
author_rank: Super Contributor
timestamp: August 01, 2019, 09:09:54 pm
content: Quote from: CJay on August 01, 2019, 11:16:57 amThen you may not be quite ready to jump into anything but entry level DSO's and their various limitations.Your mention of a incorporated 16ch LA adds to the price substantially, often in the order of 50% for the lower cost instruments but a little less if you are to crack the licensing.Have you considered moving some of your older gear along to help fund any replacement ?Of course acapablereplacement might also replace multiple bits of gear and give you further additional room on the bench.

author: nctnico
author_rank: Super Contributor
timestamp: August 01, 2019, 09:17:42 pm
content: Generally speaking having digital channels and decoding excludes the cheap older gear because decoding is something which has become mainstream not so long ago.Using a seperate USB logic analyser can be a solution to have some digital analysis features but and MSO on the other hand can also show digital signal realtime. A logic analyser can't do that.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 02, 2019, 01:35:47 am
content: Older DSOs havr problems if you are trying to look at AM envelopes or complex signals like analog video, in that they have very small memories, so reduce the sample rate drastically at long time/div settings.Newer DSOs like the DS 1054Z or the comparable Siglents do not have this limitation.I would still keep an analog 'scope for hackup, though, because there are things you can do with them easily, which are a bit messy with a DSO, even though the latter is very capable.