Need recommendations for low end 4ch oscilloscope with signal generator  - Page 1
Forum section: electronics / testgear

author: imk
author_rank: Regular Contributor
timestamp: October 01, 2025, 03:31:14 pm
content: Hello,Currently have a Hantek DSO02D10 100mhz and it is ok for my modest electronic needs most of which are logic voltage microcontroller debugging.Yes it does have a few issues which are annoying at times like locking up and for example last night it decided that the signal generation maximum output voltage was 3.6v and not the 5v i needed, so powered it off and started again.Hence as my oscilloscope need are growing I think it is time to buy something better and have four channels.I don't need logic analyzer as have DSLogic Plus, but i do need a modest signal generator for audio sinewave and logic level square wave generation.What I don't like about the siglent rigol models is they have a single set of controls for the four channels and a button to select which channel you want to adjust. (this would drive me nuts)What I like about Hantek DSO400xx series is they have separate knobs for each channel, but do i need another Hantek set of issues.So recommendations/suggestions please for modest 4 channel 100mhz oscilloscope with modest Signal Generator function and UART/i2c/SPI trigger/decodingMany thanks in advance imk

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 03:58:57 pm
content: A budget would be helpful.Older scopes tend to have independent channel control more than modern scopes. It's not limited to Siglent/Rigol.You're better off budgeting a separate sig gen and scope. If you're doing audio work, Siglent is a good choice as they have great Bode plot and FFT implementation. You can get used to the channel switching easier than you think....or save up for a used SDS5034X.If budget is a limitation, and the sig gen is the higher priority, I would get that first and upgrade your scope later when your budget allows.Thanks,Josh

author: Aldo22
author_rank: Super Contributor
timestamp: October 01, 2025, 04:05:28 pm
content: Even an inexpensive FY3200S is more versatile than most signal generators built into oscilloscopes.The FY3200S is very simple, but has 2 channels and a maximum of 20Vpp.https://de.aliexpress.com/item/1005006994683337.html

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 04:10:20 pm
content: For audio work, I would personally prefer either a higher quality AWG or analog signal generator vs a DDS. DDS sig gens would be okay if that's all a budget allows for, but the waveforms aren't awesome.The attached is a decent example of a (ETA: cheap / budget) DDS sinewave.

author: Performa01
author_rank: Super Contributor
timestamp: October 01, 2025, 07:13:50 pm
content: Quote from: KungFuJosh on October 01, 2025, 04:10:20 pmSorry, but this claim is misleading. A properly processed and filtered DDS sine doesn’t have any defects.Attached is the example of a decent DDS sine, 1 kHz from the new Siglent SDG1062X Plus.Of course, we should avoid showing the quantization steps of the DSO by using a decent 16 bit DSO with 20 bit resolution enhancement. Yet even a humble 12 bit DSO can do a decent job with resolution enhancement techniques like ERES or Average.The distortion analysis shows a THD of 0.006% for the sinewave shown – that alone should be a dead giveaway that the sine is not too far from perfect 😉

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 08:05:18 pm
content: Quote from: Performa01 on October 01, 2025, 07:13:50 pmYou're right! I should have saidcheapDDS. That's what I meant anyway.

author: Martin72
author_rank: Super Contributor
timestamp: October 01, 2025, 09:37:48 pm
content: Hi,QuoteSo no scope.OK, that was mean...You specified “low end” in the title, which for some people means a scope for $400, and for others one for $4,000.The “truth” lies somewhere in between.When it comes to scopes with a 7“ screen and no integrated generator, the choice is clear: there are only two brands.The 12-bit models from Rigol and Siglent, with Siglent embodying more of a ”pro" scope feel.In my opinion*, the SDS800X HD from Siglent is the ultimate in terms of inexpensive but very good oscilloscopes.You can read the very informative thread on this topic in my signature.If the screen size (7") is sufficient for you, as is the maximum bandwidth (200 MHz, hackable), then there's no way around it—there's simply nothing better in this price range.Together with an external (but scope-controllable) generator (e.g., SDG1000X series), you have a combination that is hard to beat without spending a lot more money.If the planned budget is larger, I can provide further recommendations.One more thing about vertical channel control:Whether you can move each channel individually or only when you select it, it only takes a few seconds...You get used to it quickly, in my experience.*) =Scopes that I own/owned/have tested/use every day at work:Rigol DS1054Z, DS2072, MSO5034, DHO824, DHO 4034, MHO5034.Siglent SDS1104X-E, SDS2104Xplus, SDS2104X HD, SDS804X HD, SDS3034X HDLecroy 93XX, LT262, LTXXX, WS432, WR9054, HDO6034A, WS-Pro 254, WS3024Z, etc.Magnova BMO 350

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 01, 2025, 09:59:33 pm
content: You're missing at least one.

author: MarkF
author_rank: Super Contributor
timestamp: October 01, 2025, 10:02:55 pm
content: Quote from: KungFuJosh on October 01, 2025, 08:05:18 pmDepending on what your requirements are, a simple AD9834 DDS chip with minimal filtering can provide reasonable results.Here is a 1KHz sine and FFT from the generator I built:Additional waveforms and the circuit design can be foundhere.Scope captures from a Rigol DS1000Z.

author: Performa01
author_rank: Super Contributor
timestamp: October 02, 2025, 06:05:56 am
content: Quote from: imk on October 01, 2025, 03:31:14 pmSeparate vertical controls have been a thing for analog oscilloscopes and early DSOs, with huge dimensions and small screens (hence plenty of space on the front panel), that were primitive and only had to control two (sometimes four) input channels.Modern DSOs have a lot more channels and also a lot more parameters per channel to control.Do you really want 16 separate vertical controls for analog input, zoom, reference and math on a low end DSO? On a higher end DSO add another 4 channels for memory traces.Apart from that, to be consequent, you'd need separate controlts for channel input coupling, bandwidth limit, invert and trace visibility as well (plus 50 ohms input selection on higher end devices).

author: tautech
author_rank: Super Contributor
timestamp: October 02, 2025, 08:10:26 am
content: Quote from: imk on October 01, 2025, 03:31:14 pmSo you might imagine and that years back was my view too....clouded by misjudgement on just how well implemented multiplexed controls can be.Take a deep breath and put aside prejudices and come to the other side where in very short time outdated views should be forgotten.

author: sprit
author_rank: Regular Contributor
timestamp: October 02, 2025, 12:39:26 pm
content: What do you think about Keysight DSOX3000 series, i think its a good option too.

author: nctnico
author_rank: Super Contributor
timestamp: October 02, 2025, 12:47:56 pm
content: GW Instek's MDO-2104EG fits the bill if individual controls are required. But it looks like individual channel controls are getting more rare these days.

author: Martin72
author_rank: Super Contributor
timestamp: October 02, 2025, 09:29:02 pm
content: Quote from: KungFuJosh on October 01, 2025, 09:59:33 pmFixed...

author: edavid
author_rank: Super Contributor
timestamp: October 02, 2025, 09:50:20 pm
content: Quote from: nctnico on October 02, 2025, 12:47:56 pmI suspect that's way outside OP's price range. However, if he could find a used or NOS GDS-1054B or GDS-1104B, that would be a good choice. I don't know if he could find one in the UK.I recently got a cheap, new in box GDS-1054B, and despite years of getting used to/putting up with multiplexed vertical controls on other scopes, I find that I still like the individual controls much better.Quote from: Aldo22 on October 01, 2025, 04:05:28 pmThat's what I would suggest also, but for some reason these cheap DDS FGs use discrete resistor DACs, so the distortion can be worse than expected, and vary from sample to sample. I'd suggest using a sound card if low distortion audio is needed.

author: Aldo22
author_rank: Super Contributor
timestamp: October 03, 2025, 08:49:40 am
content: Quote from: edavid on October 02, 2025, 09:50:20 pmSure. I didn't mention the FY3224s because of its outstanding signal quality, but because it's one of the most affordable “real” signal generators.The OP wanted a “modest signal generator function.”I just wanted to point out that it could be difficult and expensive to find an oscilloscope with a built-in signal generator that even comes close to the FY3224s in certain aspects.And by that I mean primarily the amplitude and the two channels.Built-in generators often only go up to 5Vpp or 7Vpp (without load).Something like what is shown in the attached images is often not possible with built-in generators, or else quite expensive.In any case, I would not choose an oscilloscope based on whether it has a built-in signal generator.The rest of the FY3224s is specified and documented.Anindependent measurementindicates approximately 0.2% THD.Whether that is good enough certainly depends on the application.As I said, I just wanted to show that a standalone signal generator doesn't have to be expensive.Of course, there are many better ones out there.