Picoscope 2206B/2406B vs Rigol DHO804 vs others? - Page 1
Forum section: electronics / testgear

author: G-son
author_rank: Regular Contributor
timestamp: December 17, 2023, 09:56:32 am
content: I currently have a 15 year old Picoscope with a bit lower specs than their current bottom of the barrel model (2204A), in general I am very happy with it but in some ways it is a bit limited, more so with the "new" Pico 7 software as there is a bug limiting the memory usage while streaming and being an obsolete model it doesn't seem to be a priority to rectify.What I like about my current Picoscope are things like:Portability, I can throw it and a laptop in my backpack and use anywhere, runs off the laptop battery. Not fragile, no screen to scratch or exposed knobs to break off.Ease of sharing recorded data. Waveforms can be saved as images and shared anywhere online, or as data files where anyone still can zoom, apply math channels or do whatever, just like I could do right after capturing it. Great for help with analysis.Good user interface, lots of functions in the software.Reliability. As said, it's 15 years old and still going strong. No guarantee a new one will last as long of course, but it comes with a 5 year warranty and I haven't seen many complaints about Picos breaking randomly.What I'm missing:Memory. I have 8kS for high speed signals (rarely used) or 2*2MS per waveform in streaming mode (continuous transfer over the USB, not saving one at a time waveforms in the 8kS scope buffer) for lower speed signals (max 1MS/S, half that is the practical limit to avoid cutouts in the waveform), up until the total 100MS memory the Pico 6 software allows is full, so close to 25/50 waveforms @2MS per channel.Faster streaming, or equivalent results using other methods - streaming would be unique to USB scopes, I suppose, and not a limiting factor for bench scopes and such.More than 2 channels would be nice.DC offset. I'm currently stuck with voltage ranges centered around zero volts, i.e. -20 to +20V for example. A lot of wasted resolution when I'm just looking at a signal varying between +5 to +15V. Alternatively, better vertical resolution would work, so I could zoom in without losing too much detail.Upgrading to a Pico 2206B or 2406B would solve that. They have:32MS memory buffer in the scope.I think 9.6MS/S max in streaming mode, 100MS max in one waveform (shared) using Pico 6, the newer software Pico 7 is supposed to allow even more I think. I think the auto save feature in the new software would practically allow you to keep it going until the computer hard drive is full, should you have the need to.2 or 4 channels, depending on which model I choose. There's quite a price difference, and a Rigol DHO804 would cost somewhere between those options.DC offset.Reliability? As a lot of the hardware is in the laptop and the laptop is easily replaced, a USB scope can avoid worn switches, aging power supply capacitors, scratched screens and so on. Less parts to break.Continuous software development. The 15 year old scope works excellent with the last version of the Pico 6 software from a year ago or so, the current Pico 7 software has a bug for these obsolete models but itmostlyworks. Doesn't guarantee the same applying to the future, but seems promising.The possible downsides of 2206B/2406B:It's a relatively high price for the specifications, compared to for example the DHO804. Bought locally (not a fan of international shopping for expensive items with warranties) the 2 channel would end up about $100 cheaper, and the 4 channel $150-200 more expensive. Rough numbers, I haven't checked all possible sources.The Picos are only 8 bit vertical resolution. Good enough for just about everything I do, sure, especially using the DC offset, but when you compare it to 12 bit you kind of realize there is room for improvement.The Pico 2000B models have been around for a number of years now. On one hand that means tried and true, on the other hand it means old, and that usually says you'll pay a lot for limited function compared to newer tech.The Rigol DHO 804... Well, you guys probably know that far better than I do. When it comes to bench scopes I haven't used anything newer than 1990s analog scopes. Those were in no way suitable to throw in the backpack.The possibility to have a portable USB C power supply seems nice, that could suit me well.How practical is it to share collected data?What kind of life span should we expect out of it? I'd like something that'll last quite a while, when I spend several hundred dollars.Does the Rigol has the ability to use combinations of functions for math channels? For example, in the pico I have used frequency math channel to show an engine RPM, and then applied derivative to the rpm to get a curve of how rapidly the rpm changes (with low pass filtering to avoid the curve changing so much it 's hard to interpret).Are there other good options? I don't need much bandwidth, 2 channels may be okay, 4 is better. Math channels similar to the pico would be very helpful sometimes.

author: 2N3055
author_rank: Super Contributor
timestamp: December 17, 2023, 03:24:54 pm
content: As a long time Pico user myself, my advice to you would be to stick with the Pico.Apart from numerous bugs (which are because it is new) that will eventually go away, DHO800 will be frustratingly different and will miss many features Pico has. If dynamic range and 8bit resolution of Pico is sufficient to you, Pico is superior in its capabilities.My old ADS212/100 was supported for 20 years, until some version of V6. And even then it was problem with USB/parallel converter that was problematic.As long as your scope is of modern USB versions, I would think support will be long..

author: Fungus
author_rank: Super Contributor
timestamp: December 17, 2023, 05:28:18 pm
content: Quote from: G-son on December 17, 2023, 09:56:32 amCaptured data can be saved to USB stick or saved to internal memory then downloaded over Ethernet (via FTP - it has an FTP server to access files on the 'scope).It's also quite easy to download data directly to PC using a script.Quote from: G-son on December 17, 2023, 09:56:32 amThere's no reason it won't last as long as a Picosope.Quote from: G-son on December 17, 2023, 09:56:32 amYou can chain math channels together in a sequence but the range of operators is quite limited.You can download data and process it yourself.

author: 2N3055
author_rank: Super Contributor
timestamp: December 17, 2023, 08:21:27 pm
content: In comparison to Picoscope DHO800 math is just pathetic.Picoscope has both arbitrary math and NO LIMIT on number of channels.You have libraries of probes, that can not only be arbitrary but can be nonlinear..Any Pico decodes 23+ protocols..You can decode from math channels..Etc etc...There is no comparison to any scope until you get very high up the food chain.As I said, if he does not specifically need 12 bit and can give up all other features of Pico, I would stay with Pico...

author: Martin72
author_rank: Super Contributor
timestamp: December 17, 2023, 10:29:42 pm
content: Quote from: G-sonThis is a crystal ball question thatno onecan answer seriously, simply because the product is still too new for the relevant experience to be available.Then it depends on what the question refers to.Does this refer to the electrical service life or the service life of the support for this model?Only rigol itself knows the latter.As for the electric, well, it's a $400 cheap scope, so I'd be happy with it if it lasted a few years, because it didn't cost much money.But as already mentioned, time will tell, you have the warranty period for early failures.

author: G-son
author_rank: Regular Contributor
timestamp: December 18, 2023, 12:17:07 am
content: Quote from: Martin72 on December 17, 2023, 10:29:42 pmYes, agreed, it's impossible to know when it comes to a new model, only time will tell for sure.I was referring to electrical service life, as the scope will keep working just fine even if the support stops, if the firmware in it is working day one you should be good to go until whenever the magic smoke leaks out, no support required. I suppose updated programs/drivers for communicating with computers and such may be helpful as computers get new operating systems etc, but not absolutely required for the scope to work.I was mostly thinking if people have seen any life span issues in the previous Rigol low cost scopes, 1052 and 1054Z I think those are called. If they had a habit of giving up when a few years old and out of warranty that might be an indication of what to expect out of new models too. If on the other hand even most of the oldest ones still are going strong that would be very promising.Speaking of warranty, the Rigol seems to be 3 years, which isn't bad for electronics.Picoscope offers 5 years warranty for the entire test & measurement range, so they obviously have faith in their products too.It sounds like I was leaning in the right direction from the beginning; I already have a Picoscope that has done the job well, I'm used to using the software, and I'm overall quite happy with it except for a few limiting factors that mainly is due to it being a bottom end model, and old and obsolete at that. It makes sense to keep going with a better model Picoscope for the future. A 2206B/2406B will be a big step up now, and they have a range of even better models (including 12 bits resolution and 8 channels) should I have bigger needs and more money in the future.

author: Fungus
author_rank: Super Contributor
timestamp: December 18, 2023, 12:25:27 am
content: Quote from: G-son on December 18, 2023, 12:17:07 amAbsolutely not.

author: Martin72
author_rank: Super Contributor
timestamp: December 18, 2023, 12:36:43 am
content: QuoteUnfortunately, it is not possible to draw conclusions from one to the other if it is not known whether the same components are used.In today's world, the opposite is more likely to be the case, i.e. everything has to be as cheap as possible.However:Either something fails in very early times or it lasts beyond the general stated MTBF.This is why it is relatively easy for manufacturers to offer a longer warranty.Either it fails very early, or well after the warranty - if this were not the case, the warranty periods would be adjusted accordingly.For some projects, for example, we carry out so-called burn-in tests; if they survive this ordeal, they will also meet their MTBF.