Recomendations for first Oscilloscope - Page 1
Forum section: electronics / testgear

author: AdrianLevi
author_rank: Newbie
timestamp: April 27, 2023, 11:39:10 pm
content: Hello,I realise this has probably been asked a thousand times but the search wasn't useful (or my search skills are lacking).I'm looking for a reasonably low cost first oscilloscope for power supply repair, audio and hobbyist microcontroller work. If it could decode serial signals that would be a fantastic bonus (RS232, 485, I2c ...)I was looking at the Jaycar scope QC1938 but was wondering if there were better scopes for the same or similar price range, including scopes that can be hacked for expanded features at the same price point.Please help, there's almost too much information out there to rule out what I need/don't need. 2nd hand would be fine but there seems to be a lot of risk involved with 2nd hand test gear!

author: jasonRF
author_rank: Regular Contributor
timestamp: April 28, 2023, 01:10:08 am
content: That looks suspiciously like a rebadged Hantek DSO2D10 for $549.https://www.jaycar.com.au/100mhz-digital-oscilloscope-with-8m-memory-depth/p/QC1938If that is correct, there is a thread on those scopes which usually sell for much much less. To me they look like a headache. Look at the gazillion other scope recommendation threads and you will find the usual recommendations from Siglent or Rigol.jason

author: tautech
author_rank: Super Contributor
timestamp: April 28, 2023, 01:18:45 am
content: Quote from: AdrianLevi on April 27, 2023, 11:39:10 pmWelcome to the forum.TBH if your are to get into sniffing protocols you's be better served by a 4ch DSO.For a similar price you can get this locally:https://appvision.com.au/index.php?id_product=502&id_product_attribute=0&rewrite=siglent-sds-1104x-u-100-mhz-4-ch-super-phosphor-oscilloscope&controller=product

author: TopQuark
author_rank: Frequent Contributor
timestamp: April 28, 2023, 02:26:14 am
content: Quote from: AdrianLevi on April 27, 2023, 11:39:10 pmDo you have a budget in mind?

author: .RC.
author_rank: Frequent Contributor
timestamp: April 28, 2023, 03:10:12 am
content: Quote from: tautech on April 28, 2023, 01:18:45 amThis seller sells some at a cheaper price point then the official Siglent seller. Grey imports maybe? They do not say in stock anywhere (or else I am probably blind and missed it).https://www.wavecom.com.au/products.php?prod_cat_main=Oscilloscopes

author: EEVblog
author_rank: Unknown
timestamp: April 28, 2023, 03:11:30 am
content: Quote from: AdrianLevi on April 27, 2023, 11:39:10 pmNope, don't touch the Jaycar ones (rebadged Hantek's). You can get way better value elsewhere.For the same price stocked in Australia you can get a 4CH Siglenthttps://www.ebay.com.au/itm/334342816579

author: tautech
author_rank: Super Contributor
timestamp: April 28, 2023, 04:01:07 am
content: Quote from: .RC. on April 28, 2023, 03:10:12 amWavecom is AFAIK supplied from IPD and has been selling Siglent products for a while now.FYI the official AU distributors are listed here:https://int.siglent.com/map/

author: tggzzz
author_rank: Super Contributor
timestamp: April 28, 2023, 09:06:40 am
content: Quote from: AdrianLevi on April 27, 2023, 11:39:10 pmGeneral principle is that a scope is an analogue domain tool used to view analogue waveforms. Sometimes those analogue waveforms areinterpretedby the receiver as being digital signals. If the analogue signals are imperfect (voltage, timing, noise, transitions) then they may be misinterpreted by the receiver. Hence use a scope to ensure signal integrity, i.e. that the analogue waveforms will be correctly interpreted. After that, flip into the digital domain and use digital tools (logic analyser, protocol analyser) to debug digital signals and the messages contained in the digital signals.What you want is a tool that lies idle until a message to "address 59" or an "overload occurred" or whatever message occurs.The analogue waveforms contain a lot of information that is completely irrelevant in the digital domain, and the digital signals are far more information than is easily captured in the digital domain. Hence the first benefit of flipping to the digital domain is that the digital domain tools allow you to concentrate on what is important, by triggering on themessage informationand filtering out the "boring stuff". The second benefit is that for i2c, spi and similar, there areveryinexpensive logic/protocol analysers available - and some allow you to transmit signals as well as simply analyse them.You may find that some scopes claim to decode digital signals, but the decoding is very limited - e.g. only the trace on the screen is decoded, and the rest of the stored trace is ignored.Careful use of a (cheap) LA/PA/printf() statements may mean that you only need simpler and cheaper scopes - and that you won't be limited by the features (and lack of features) in any single tool.Apart from that, if you want to "repair power supplies", then be aware that incorrect use of scopes and scope probes might damage the power supply, the scope, and even you. Make sure you use theright class of probe. You may need to leave budget available for them. FFI see the references given inhttps://entertaininghacks.wordpress.com/library-2/scope-probe-reference-material/

author: EEVblog
author_rank: Unknown
timestamp: April 28, 2023, 10:23:15 am
content: BTW, I would not buy a 2CH scope these days when a 4CH can be had for an entry level price. You'll never regret getting a 4CH scope. Everything else is secondary IMO.