A digital oscilloscope for 300-350$ - Page 1
Forum section: electronics / testgear

author: Gwendam.753
author_rank: Newbie
timestamp: June 28, 2019, 07:24:33 pm
content: Hello,I'm a beginner in electronics, and I'm going to buy a oscilloscope. I already have a analog oscilloscope, but it doesn't work.So I decide to buy a digital oscilloscope, because it's more technologically advanced (I have a HAMEG HM203-7), and it's less likely to break down.I am really interested in the siglent 1072CML+ (70MHz, that's enough for me), is it a good oscilloscope?I don't need to perform very accurate signal analysis. So I think this oscilloscope can be very suitable for me.Thank you for advising me on my choice.

author: tautech
author_rank: Super Contributor
timestamp: June 28, 2019, 09:11:13 pm
content: Compared with more recent offerings buying the 70 MHz CML+ is selling yourself short.The main reason is the smaller memory depth which restricts the capability of the modern digital storage scope.As just a basic scope they work fine but they are not very well featured.In recent times I chose not to stock them (SDS1102CML+) however after a few inquiries I got some more in for buyers not wanting to spend too much, but guess what happened.............they don't sell at all.SDS1202X-E is a far better choice, better featured, faster, 200 MHz, great FFT, better UI and so on.Good luck with your hunt.

author: wraper
author_rank: Unknown
timestamp: June 28, 2019, 09:19:06 pm
content: Yeah, 1072CML+ is barely better than how entry level oscilloscopes were 10 years ago. SDS1202X-E is way better bang for the buck.

author: nctnico
author_rank: Super Contributor
timestamp: June 28, 2019, 09:19:56 pm
content: Check this topic:https://www.eevblog.com/forum/testgear/first-oscilloscope-for-third-year-ee-student/

author: 2N3055
author_rank: Super Contributor
timestamp: June 28, 2019, 09:21:46 pm
content: I don't want to sound harsh, but there are literally 100s of topics with same theme. Search a bit on the forum, this question was answered many times in great details already. No need to start it all over again... Seriously...It's all there.

author: Fungus
author_rank: Super Contributor
timestamp: June 29, 2019, 07:42:00 am
content: Quote from: 2N3055 on June 28, 2019, 09:21:46 pmI'm not sure there's one "for 300-350$"

author: Gwendam.753
author_rank: Newbie
timestamp: June 29, 2019, 08:11:09 am
content: Effectively the Siglent SDS1072CML+ is a little cheaper but he isn't/hasn't :QuoteI will consult the opinions and reviews on the Siglent SDS1202X-E. Many electronics engineers have this device and it's cool to learn how I can use it and if I have a problem, it may be easier to find the solution.Also, I think I'm going to buy the Siglent SDS1202X-E, (it's a present for the result of my final exam).Thank's you for your answers.

author: RoGeorge
author_rank: Super Contributor
timestamp: June 29, 2019, 08:42:37 am
content: RIGOL DS1054Z- 4 channels, 1Gsa/s, initial specs are for 50MHz, but it can be unlocked for 100MHz, protocol decoding, FFT, SCPI on LAN/USB, very good build quality, etc.Hard to beat that performance/price, even after so many years, being an old model pays off here because most of the bugs were already discovered and fixed.LATER EDIT:Bought mine from Batronix, very good prices for EU.

author: Fungus
author_rank: Super Contributor
timestamp: June 29, 2019, 11:04:44 am
content: Quote from: Gwendam.753 on June 29, 2019, 08:11:09 amI wouldn't buy something with only two channels these days, not unless youreallyneed something thatonlythe Siglent can do.Many, many more electronics engineers have the Rigol DS1054Z.

author: Gwendam.753
author_rank: Newbie
timestamp: June 29, 2019, 11:52:36 am
content: Why I have to use 4channels at the same time ? Can you give me an example please ?

author: DDunfield
author_rank: Regular Contributor
timestamp: June 29, 2019, 12:25:26 pm
content: Quote from: Gwendam.753 on June 29, 2019, 11:52:36 amYou don't *have* to use 4 channels at once, you can use anywhere from 1 to the maximum on your scope.Most of the time, I only use 1 or 2 channels, but there are still plenty of times where it's really nice to be able to see more than two signals at once.Happens a lot in digital serial buses you might want to see Select, Clock, Data-in and Data-out at the same time.Or in analog, you might want to see the input to an amp, the output from the amp and some feedback signal partway though it, and maybe watch what the power supply is doing.I got along with 2 channels for years, thinking that I didn't need more ... but you'd be surprised at the uses you find for those extra channels, and I wouldn't give them up now.Rigol DS1054Z sounds like exactly what you are looking for - I haven't researched in a while, but I think it's probably still the best bang for the buck.Dave

author: RoGeorge
author_rank: Super Contributor
timestamp: June 29, 2019, 01:23:42 pm
content: Quote from: Gwendam.753 on June 29, 2019, 11:52:36 amVery useful when you have it. After getting used with 4 channels, you'll never want to go back to 2 again. Two is not enough, especially when working with digital signals.Examples:- Repeatedly switching one probe between different measuring points can become a tedious task (while tuning a parameter then checking the tuning results in more than 2 points), the more probes you have, the better.- Automated testing/measuring, this shows up only if you have a production line (plug all the probes, then start a program to check the functionality in 4 points at once)- Proper SPI decoding is not even possible without 4 channels- Measuring a signal at input and output simultaneously, for both current and voltage (to improvise a two ports VNA - Vector Network Analyzer)- Measure phase between more than 2 signals (e.g. for an SDR, see the incoming signal and the I and Q outputs, and a 4'th probe to synchronize with the signal generator)- Simply having more probes and channels is better than missing them (as a redundancy in case of failure, more probes mean less wearing for each probe, or simply because being too lazy to keep switching the probes between different measuring points)- Data logging from more than 2 points (the oscilloscope can be connected to a computer, and measure/log signals for a very long time, e.g. I spied for over a week on the fridge's signals for compressor, defrost, fan and door switch, in order to see why sometimes the compressor was not working: found out that only during some very hot days the door switch contacts become wiggly, so the fridge thought somebody is keeping the door open and refused to start the compressor)- As a general rule, as soon as you'll have something extra, you'll find a usage for it

author: Fungus
author_rank: Super Contributor
timestamp: June 29, 2019, 01:26:30 pm
content: Quote from: Gwendam.753 on June 29, 2019, 11:52:36 amYou don'thaveto use 4 channels all the time but I can almost garantee that there will be a time when you need more than 2, especially if you do anything digital at all.And if you have more, you'll find ways to use them even though it isn't necessary. It's just nice to be able to do it.It's a bit like a car with four seats instead of two. You might not normally (or ever) carry passengers but you can still put shopping in the back seat (and it can often save you making two journeys).Quote from: RoGeorge on June 29, 2019, 01:23:42 pmYep. I use mine a lot for software debugging on Arduinos, eg. Change an output pin when a condition happens, so I can see it on screen (and how frequently).

author: Old Printer
author_rank: Frequent Contributor
timestamp: June 29, 2019, 01:36:26 pm
content: Bottom line is you need to do your own homework. The top 3-4 candidates for this choice have been dissected to death and all of the information is here, but if you really want the best scope for you there is no short cut. I spent two years making my choice and it will probably be two more before I know if I made it right, or if it really mattered that much to start with. Happy reading.

author: nctnico
author_rank: Super Contributor
timestamp: June 29, 2019, 05:23:55 pm
content: Quote from: Gwendam.753 on June 29, 2019, 11:52:36 amLook at the input signal, output signal and some point in between. For an SPI bus you'll need at least 3 channels. You really shouldn't ask why not to buy a scope with 4 channels. Nowadays 4 channels is standard for a good reason.

author: bob91343
author_rank: Super Contributor
timestamp: June 29, 2019, 05:42:47 pm
content: I found a short cut. I bought a used HP unit for a bit over $200 on ebay. I am more than satisfied. It has four channels and goes to 500 MHz.Don't ignore this path. Sure an old unit may not do everything, and it might be large and heavy, and it might need some repair. But for what you get, the price is hard to beat. Mine has FFT and a great feature of setting itself for a nice display with one button press. It adjusts itself for gain and sweep speed. It also measures frequency, amplitude, and some other nice things. When I got mine it was missing one knob. I found one in my junkbox that fit and there seems to be nothing else wrong with it.Modern units easily outperform it on all fronts but for my uses it's nearly perfect.

author: 2N3055
author_rank: Super Contributor
timestamp: June 29, 2019, 06:05:12 pm
content: Quote from: bob91343 on June 29, 2019, 05:42:47 pmGiving advice to a total beginner to buy 25 year old scope he's incapable to verify, diagnose and repair is not what I would do.Especially if money is tight. He's better of with entry level unit that works reliably and has 3 year warranty, than some unknown thing.Also, OP is in Europe. We said it many times before, but I will repeat.Those "great deals" don't exists in Europe, we don't have same instruments surplus that you have in USA.There are no good instruments to be had for 200 USD locally in EU. Period.Shipping of a 25 KG instrument from USA to EU cost 100-200 USD alone, and than that cost is added to instrument cost, and then you pay 22-25% VAT on whole sum. So your 200 USD scope become s 500 USD by the time it reaches EU.Also none of those instruments have 10% of capabilities even the cheapest new scope does.I know you mean well and just want to help. It's just it's not applicable outside USA.What I would do though is that rigol.eu right now has ex demo unit DS1054Z for sale for 290 € with 2 years warranty. Although, that is only 50 € less than brand new unit with 3 year warranty.....

author: Wigo
author_rank: Contributor
timestamp: June 29, 2019, 06:16:36 pm
content: Quote from: 2N3055 on June 29, 2019, 06:05:12 pmYou are totally right, the "nice, dirty and cheap" deals are not available in europe that often. But i made the experience myself that it is possible but it needs some time. I had been in nearly the same position as the OP and i told myself: Hey you do not need it right away. Have a look arround on various sites and platforms and wait. And in the same time save some more money to buy a decent new unit in a few months time. And what happened? I found an Agilent 56422D for 150€ pickup complete with all the probes including the logic probes and the manual in a nice used condition obly 30km away. The only two things to to on the scope where that i had to change the battery (which is easy doable if you have a little time to gather the information required) and second to fix a broken carrying handle.But i am in the situation now that i need to look at 3-4 analog signals at once and so i am taking the same approach with buying a "new" 4 channel scope.To conclude, it is doable in europe but it takes rime and luck.And for the rest read about the scopes you consider. Read tests on forums and watch videos and in the and answer the question how much am i willing to pay for a tool? Or is the tool i can afford the one that i need or do i need to save a little more money?

author: wraper
author_rank: Unknown
timestamp: June 29, 2019, 06:27:40 pm
content: Quote from: bob91343 on June 29, 2019, 05:42:47 pmThat's not a shortcut but a piece of trash for most uses. What's a point from having 500 MHz if it cannot do real time sampling? Those 500MHz are only good for very niche use. Also it's a boat anchor cluttering your bench. And as said above does not work for Europe.

author: 2N3055
author_rank: Super Contributor
timestamp: June 29, 2019, 06:39:49 pm
content: Quote from: Wigo on June 29, 2019, 06:16:36 pmAnd it's exactly what I'm saying. You spent 150 € on something that very soon became apparent that it's not good enough, and now you will have to buy a scope again, and you will have 150€ less to buy a good one... So you would have been better of just buying good one in a first place, and skip the old clunker.Don't get me wrong. Agilent 56422D has a special place in my heart, it was spectacular when new, back then. Today, it's an old clunker with a carburetor, tired and limited.....Also, any scope , ANY, is better than nothing. But for the same money, you get today's technology for today's problems..

author: bob91343
author_rank: Super Contributor
timestamp: June 29, 2019, 07:43:42 pm
content: As I said, my boat anchor may be inadequate for some modern applications but for what I need it works great. Its size isn't a problem and it shows me what I want to see in the stuff I probe. Certainly for the cost it's a bargain.I also have analog units that have their places as well. My entire workbench cost was very low and I can do everything I want with it.

author: GigaJoe
author_rank: Frequent Contributor
timestamp: July 01, 2019, 04:53:24 pm
content: 0.1 cent:having siglent, rigol, and boat anchor. anchor collecting dust - just laughing how little it can, most in use siglent, 2 ch mostly sufficient, rigol hesitating to sell, it has a diff options comparing to siglent, software better polished, and 4-ch.