Author Topic: Is the Rigol DS1054Z still the best buy for a cheap entry level oscilloscope?  (Read 17424 times)

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Offline JohnnyMalaria

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What's the purpose of old, failing hardware that isn't calibrated anymore? Training? Like, those toys you played with when you were 1-4? You can't trust what it tells you, so the only thing you can do with it is play.

Because old hardware such as analog CRT oscilloscopes can still blow modern DSOs out of the water in some regards, particular the budget DSOs.

I have a DS1104Z (100MHz version of DS1054Z) that I bought last year and a '74 Tektronix 475 CRT scope. For me, XY mode is essential so I can monitor my experiments properly. I don't care if it is "precise". As long as I'm within a couple of percent, that's more than sufficient. I was excited that the Rigol had XY mode - until I came to use it. Here are some short side-by-side video clips comparing the two.



I have yet to come across anything that beats the old CRT scope for this. I can tell at a glance if my equipment (or the thing it is testing) is behaving correctly. It's the best tool for that job. To dismiss something because it is old and analog is short-sighted. I'm all three.
Tell me it can't be done and I'll do it. Or give it a damned good try.
 
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Offline sibeen

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No, no, no, that can't be right, JM.

Nice video :)

I'd just find it strange that someone who doesn't own a cro (yep, I'm old) can be so dogmatic about the use and care of the beasts.
 

Offline rstofer

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I bought a Tek 485 from eBay about 12 years ago for around $200 and it still works fine.  It was well used when I got it and it served up until I bought my DS1054Z a while back.  It still has more bandwidth and it works well for things like X-Y mode.  No repairs but it probably isn't anywhere near in calibration.  I don't really care much about calibration, scopes are 'about' kinds of instruments.  It doesn't seem to get the wrong answer either so it's close enough.

I don't see the day when a DSO will replace entirely the capabilities of an analog scope - particularly in affordable bandwidth.  It's the same the other way too, I enjoy the measurement features of a DSO.

Both scopes will be staying right where they are.
 

Offline Old Printer

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I bought a Tek 485 from eBay about 12 years ago for around $200 and it still works fine.  It was well used when I got it and it served up until I bought my DS1054Z a while back.  It still has more bandwidth and it works well for things like X-Y mode.  No repairs but it probably isn't anywhere near in calibration.  I don't really care much about calibration, scopes are 'about' kinds of instruments.  It doesn't seem to get the wrong answer either so it's close enough.

I don't see the day when a DSO will replace entirely the capabilities of an analog scope - particularly in affordable bandwidth.  It's the same the other way too, I enjoy the measurement features of a DSO.

Both scopes will be staying right where they are.

Ditto on this. I have a 475 that I bought on ebay about 12 years ago as well. I worked fine then and does so now. I have  a 2225 that I paid $100 last year and it works great as well. I look forward to getting my first DSO soon, but these two "dinosaurs" are not going anywhere, and with full factory service manuals for both I will likely be able to keep them running for as long as I am. :)   For the price these things can be had for now I think it's silly not to have one.
 
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Offline IDEngineer

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I'll carefully tread into this whole "are analog scopes worth having anymore?" discussion.

This thread's originator said "I've never used an oscilloscope before." With that in mind, I recommend he START with an analog scope. You can often find them on Craigslist, eBay has lots of them, and (since his username looks like a ham call sign) hamfests commonly see a few and/or local hams may have one they're willing to part with. Plus he has an offer for a FREE one, doesn't get much better than that.

Don't view this as "No, I don't want it. It will set the day I get a proper scope back even further." Buy the digital scope on the same schedule you had planned. But LEARN about scopes by starting with the analog unit. Why? Because you will be "closer" to the signal with the analog scope. Digital scopes, with their sample memory and triggering that moves around within that memory, add layers of abstraction that you don't suffer with an analog. Analog scopes also have things I don't often see on digitals, like linearly variable amplitude and sweep. You won't spend lots of time on them but they are immensely valuable in acquiring a gut-level, intrinsic feel for how a scope actually works. The analog scope doesn't need to be in calibration. It doesn't even need fancy features. You need a horizontal sweep, a vertical amplifier, and a triggering circuit. Just those three things will teach you more than you realize, and all of that deep understanding will transfer directly to your new digital scope and make you far more proficient with it. Remember, you said "I've never used an oscilloscope before." The more, and easier, you learn about what a scope actually does, the better you will be at using ALL scopes.

If it were me, I'd fire up the analog scope, switch its trigger to Auto, and put some repeating signal on the input. Even just the scope's own integrated square wave (used for calibrating probes) will work. You'll see a scrolling waveform on the screen. Play with the vertical sensitivity and get a feel for what happens on the screen. Play with the variable sensitivity knob too.

Then play with the horizontal timebase. See how the waveform's visibility changes as you speed and slow the sweep rate. There will be a point where, perhaps with the help of the variable sweep knob, you can almost kinda sorta get the waveform "stable" and see its shape.

This is already more visibility than you had with no scope at all, and even if you don't realize it you're training yourself to treat the scope not as this discrete "tool" but as an extension of yourself. Like wearing glasses, eventually you don't think about the tool and the tool just becomes part of YOU. You're already using two of the main sections of the scope.

Now, it sure would be nice if you could stabilize that waveform on the screen, right? So it would stop moving around and you could really examine it. That's what the third main section, the triggering system, does. Switch the triggering system to Normal. If the screen went blank, don't panic... the triggering system will only let the trace move across the screen if the input voltage crosses the trigger level threshold. Now try varying the trigger level until the trace (re)appears. Note that it's stable now! The trigger system only lets the horizontal sweep occur when the input voltage crosses the trigger voltage level. You change that voltage with the trigger level knob.

If you have access to a sine wave (this example doesn't work well with a square wave - can you figure out why?), use that and vary the trigger level. You'll see the sine wave move left and right as you change the trigger level, because as you change the trigger level it matches the sine wave at different places. Also try inverting the trigger slope. See what happens to the waveform on the screen.

Now, find another signal source. Maybe a serial data stream, like RS-232 or CAN or USB or something. By using Normal trigger mode you will probably be able to get a psuedo-stable display, and by varying the horizontal timebase you should be able to fill the screen width with roughly one byte/packet. The waveform may be changing, but that's just the varying bits in the data stream.

Now, without changing anything else, switch to Auto trigger mode. Lots of horizontal scrolling now, right? Can you explain why? Hint: Auto mode just mindlessly starts the next horizontal sweep when the previous one finishes. How does Normal mode differ from that?

Play around - and I really do mean PLAY - with the analog scope like this, looking at every signal you can find. An hour or two of this and you'll develop an innate sense of how to tune the scope to the signal. You won't look for the "right" button or knob, your fingers will just go there. You'll stop thinking of the scope as separate from yourself, and start thinking more about the signal you're investigating. And all of this will transfer directly to your new digital scope. You'll be more proficient with it, faster, than without the analog scope experience.

Could you do this starting with a digital scope? Sure. But it is my humble opinion that it will take you longer to become equally proficient, and you miss out on the "scope zen" that you'll quickly develop with the analog scope.

I could go on and on, but hopefully you get the idea. Hope this helps!
 
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Offline JohnnyMalaria

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 :-+ :clap: Everything IDEngineer said.

My analog scope is still my "go to" - comes on in a matter of seconds and its so easy and quick to fiddle with the horizontal and vertical knobs to find what I need to know.
Tell me it can't be done and I'll do it. Or give it a damned good try.
 

Offline tautech

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IDE overlooks some very important points for someone getting their first scope.

Many of the points he makes are relevant and some aren't.
With a CRO you have to 'drive' it and to do so some understanding of the controls are needed but just like any scope ever made the owners manual has some form of basic instruction of rudimentary usage.
Engaging of the grey matter between ears yields more reward than twiddling with knobs.

A DSO on the other hand has Autoset in which the scope adjusts to give the user a basic waveform from the connected source. For the DSO novice this 'gets you going' from which you can make further control adjustments to look at the signal in greater detail. The best advice I had was to know of the expected waveform before connecting to the signal source. That was great advice !
Frequency is not so important as amplitude where mistakes can place you, the DUT, scope and probe at risk.

I was a beginner once too and although my first CRO use was over 45 years back at HS (no usage instruction other than what I'd read in books) it wasn't until in my 40's that I was given my first scope.....and that I had to fix first !
At that time I was well old and wise enough to accomplish the repairs with minimal risk and thereafter owned and repaired numerous CRO's and early Tek DSO's and that's when I recognized DSO's were the way of the future.
I still have 5 CRO's, some needing repair and I never use them.
In general my experience has shown me some parts of the circuitry in CRO's are under significant stresses, particularly the EHT (-1 to 3KV), vertical output amps (70-160 V) and PSU let alone the now aging electrolytic caps that are well past their 'best before' dates.

To advise a beginner to get, maintain and use a CRO today is foolhardy IMHO, in particular for the maintenance or repair of HV supplies, something a beginner in electronics has neither the experience or tools to perform repair to any sort of success.

Like buying an old car, if you have the tools and ability to keep it on the road then great, if you don't it could let you down and/or cost you money.
New on the other hand offers guaranteed performance and a calibration cert.
New gear also has a warranty so that additional $ can be well spent for piece of mind.

In the end available budget should dictate CRO or DSO purchase along with the buyers ability to keep an old scope going or not.

Edit to add.
Whatever scope a novice selects it is highly likely over time they'll grow out of it, that is the basic functionality won't be enough as skills and knowledge grows. Modern DSO's and their wide range of capabilities will serve a owner for many years.
« Last Edit: May 25, 2018, 10:43:10 pm by tautech »
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Offline JohnnyMalaria

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I think this comes down to the DSO itself. I have the 100MHz version of the one the OP is asking about. I bought it for portability. Having 4 channels is great and I use the FFT feature, crude as it is. But, I suspect because it is a budget DSO, some very simple things take unnecessary button pushes and knob twiddles. e.g., moving a trace up or down. It is slow to respond and not at all smooth. Not having things like the timebase or vertical gain actually on the knob is annoying, too. I have to think about the buttons I have to press rather than just turn the knob and this gets in the way of thinking about what I'm trying to do work-wise.

I haven't used a high-end DSO and I suspect the experience is much more gratifying. My CRO is almost as old as me and hasn't needed any repair (at least since I got it 15 years ago and according to the Boeing aerospace engineer who had it before me).

If budgetary constraints mean choose one over the other then, sure, the DSO makes sense. But if you can get a functioning CRO for $100 or less to learn the basics then it's a wise move. Or if you can find someone with one to show you.

To me, it's like learning to drive a car with an automatic transmission vs. a manual. Do you need a manual? Probably not. Does learning how to drive one make you understand what makes the car react to things the way it does and to understand the "feel", absolutely. The difference in this case is that learning the manual is harder whereas learn the basics of an oscilloscope with a CRO is much easier. I'd also say that when someone first learns to drive a car, they usual get an old one rather than a brand new one with all the last "features" that, to my mind, encourage lax/dangerous driving. At the end of the day, though, you have to ask yourself "why do I need an oscilloscope and what features are critical and which are just fluff?"
Tell me it can't be done and I'll do it. Or give it a damned good try.
 

Offline IDEngineer

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A DSO on the other hand has Autoset in which the scope adjusts to give the user a basic waveform from the connected source.
Sure, you can use a DSO's "AutoSet" feature. But you aren't learning nearly as much if you do.

It's all personal preference. If you just want to see a waveform, AutoSet gets you there quickly. But if you really want to understand how a scope can be an extension of your mind while you're Engineering something, AutoSet is a crutch.

Please note I encouraged our newbie to proceed with his DSO purchase. I just think he'll be a better DSO driver if he plays with an analog scope first. YMMV.
 

Offline tautech

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I think this comes down to the DSO itself. I have the 100MHz version of the one the OP is asking about. I bought it for portability. Having 4 channels is great and I use the FFT feature, crude as it is. But, I suspect because it is a budget DSO, some very simple things take unnecessary button pushes and knob twiddles. e.g., moving a trace up or down. It is slow to respond and not at all smooth. Not having things like the timebase or vertical gain actually on the knob is annoying, too. I have to think about the buttons I have to press rather than just turn the knob and this gets in the way of thinking about what I'm trying to do work-wise.
How so ?  :-//
Most DSO's have a 'Fine' function on the vertical attenuator. Not something I use a lot but occasionally it comes in handy. Variable timebase on the other hand is a feature I don't miss in a DSO as it's too easy for the novice to leave it in the UnCal (unlocked) position. Then any frequency measurement you're trying to read from the graticules is sure to be way off.
The modern DSO and even the old Tek ones I've had can be driven just as you would a CRO or manual car as the controls do the same actions, it's just there are more of them......something to grow into.
I've mentioned AutoSet, it's something that helps the novice, not something that replaces normal scope usage.
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Offline bd139

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When I had a DSO, which I don't now as I have minor tinnitus and the Rigol fan felt like someone shaking a can full of nuts in my ear, I shamelessly whacked auto most of the time and then tweaked the result.

IMHO I'd hit a digital one if you're a new user. Even as a relatively old timer who has just spent the entire evening dissecting bits of analogue oscilloscopes all over the living room, I've got to say that as a beginner you need something that you know (a) works and is (b) likely to remain working and (c) accurate. Learning with crap or uncertain tools is doing yourself a big injustice.

The only problems with budget DSOs is really a combination of soggy controls, incredibly overloaded functionality (each control does way more than N things you were expecting) and bugs.

Personally I like the mid-ground. In 1994, HP kicked out a line of oscilloscopes, the 546xx line, which felt like and performed like an analogue scope but was a digital unit. Very nice pieces of engineering and even 24 years later, I think from an interface perspective they are better than any DSO I've used from Rigol, Tek and Agilent.
 

Offline The_Boots

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I know I'm new at this, but not having used an oscilloscope since college, I got a Tek 475 off Craigslist as my very first scope. In the three hours where it worked (before it died in a POP), I think I learned more about oscilloscopes, how they work and what they're good for than in either of my electronics classes back over a decade ago. I don't think I could have gotten that insight from a digital device because there's a disconnect there. You aren't seeing the actual signal itself-- just a series of samples of it. There's a physical connection between the electricity being measured and the trace. Being closer to the raw waveforms really helped me learn. Honestly, when it died I was SUPER bummed, because I was just starting to understand just how amazing a piece of tech it still is. Tons of fun! Plus, now I have an aspirational repair project for when I feel ready. This is not to say that I don't have an order for an SDS1104X-E (backordered! 😢), but I don't regret getting that old Tek. If you have an offer for a FREE analog scope, I honestly think you'd be nuts not to jump on it. If not as a usable scope, then as a fun thing to play with and learn from!
 

Offline JohnnyMalaria

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I think this comes down to the DSO itself. I have the 100MHz version of the one the OP is asking about. I bought it for portability. Having 4 channels is great and I use the FFT feature, crude as it is. But, I suspect because it is a budget DSO, some very simple things take unnecessary button pushes and knob twiddles. e.g., moving a trace up or down. It is slow to respond and not at all smooth. Not having things like the timebase or vertical gain actually on the knob is annoying, too. I have to think about the buttons I have to press rather than just turn the knob and this gets in the way of thinking about what I'm trying to do work-wise.
How so ?  :-//
Most DSO's have a 'Fine' function on the vertical attenuator. Not something I use a lot but occasionally it comes in handy. Variable timebase on the other hand is a feature I don't miss in a DSO as it's too easy for the novice to leave it in the UnCal (unlocked) position. Then any frequency measurement you're trying to read from the graticules is sure to be way off.
The modern DSO and even the old Tek ones I've had can be driven just as you would a CRO or manual car as the controls do the same actions, it's just there are more of them......something to grow into.
I've mentioned AutoSet, it's something that helps the novice, not something that replaces normal scope usage.

For me, the frustrations of my budget DSO are: poor fluidity of the interface, overloaded buttons/knobs that mean simple changes require multiple actions, cluttered display without being unable to get rid of stuff I don't need, half-assed implementations of potentially useful functions (e.g., FFT). Nevertheless I'm glad I've got it and my CRO, too.
Tell me it can't be done and I'll do it. Or give it a damned good try.
 

Offline BravoV

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For me, the frustrations of my budget DSO are: poor fluidity of the interface, overloaded buttons/knobs that mean simple changes require multiple actions, cluttered display without being unable to get rid of stuff I don't need, half-assed implementations of potentially useful functions (e.g., FFT). Nevertheless I'm glad I've got it and my CRO, too.

The word "budget" as in the "budget DSO" exist for a reason.  ;)


Offline IDEngineer

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Quote
I'm glad I've got it and my CRO, too.
This is what all of us are saying. Not that an analog scope substitutes for a digital scope, but that they complement each other - particularly when an analog scope is used to gain a gut-level understanding of how an oscilloscope works. And given that an analog scope can be had today for next to nothing (or, in the original author's case in this thread, actually nothing!), there's really no reason not to give yourself the advantage of that education. Again, the analog scope doesn't have to be calibrated... doesn't need all of its features working... note in the recent post above how that author felt from just three hours of education on an analog scope. Why deny yourself that advantage when it costs (next to) nothing?
 

Offline Doctorandus_P

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I bought a Rigol DS1052E ... years ago, long before the the1054z was introduced.
It's an OK scope, and I do not really need a better scope, but I'm thinking of buying a Siglent as an upgrade "just for fun".

- Much bigger screen, more info, less zooming. (Always a bit of a struggle on the old DS1052E.)
- On the Rigol you always want to turn the menu's of, because of the small screen. (extra distraction).
- Higher vertical resolution on the monitor (Rigol has barely enough vertical pixels for the 8-bit resolution).
- Annoying rotary encoders on the Rigol. This is a very common point of failure. (Is that also true for the newer Rigol's?)
- Siglent has Ethernet, (but unfortunately very slow screen update over Ethernet).
- 4 channels, with protocol decoding can be used as mixed Scope / Logic Analyser.

As a Logic Analyser, I'm quite content with the cheap ( < EUR10) "24MHz 8ch" boxes from Ali / Ebay / China, with Sigrok / Pulseview.
But these lack the combination of Digital & Analog, which may be handy sometimes.
 

Offline IDEngineer

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One more thought....

Some kids like to claim that they don't need to "learn" math because their advanced calculator does everything for them. I'm reminded of that when I think about relying on a DSO's "Auto" function. You'll may get a stable display, just like the calculator may give you the correct numeric answer, but neither one means you understand what happened to get there.

YMMV, just my $0.02, etc.
 

Offline bd139

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Auto is no different to an auto ranging DMM IMHO. Use it all the time. Easier than pissing around in the layered controls.

Interestingly Philips did analogue scopes with auto.
 

Offline BravoV

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Auto is no different to an auto ranging DMM IMHO. Use it all the time. Easier than pissing around in the layered controls.

Interestingly Philips did analogue scopes with auto.

Same as the venerable Tek CROs.

Offline Dubbie

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I agree with Tautech,

I don't know that there is much educational value in starting out with a CRO.
I started with a digital scope and to be honest, I didn't take long to learn how to use it. By far the hard bit of electronics is knowing what you are looking at represents, not how to look at it.
I think the whole analog vs digital scope question is almost irrelevant for a beginner. Just get a digital scope, unless you really really have no choice but to use a CRO.

Using a CRO is NOT going to make you better at electronics despite what some posters would have you believe. You will only get better by making lots of projects and reading and applying theory.

A scope is not rocket science. You can become basically competent with one in an afternoon of playing around. learning to design good robust circuits can take a lot longer than that  :D
 
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Offline JS

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Auto is ok when trying to capture a steady square-wave, not so much for odd pulses like transmision line reflection or odd one offs events or one in a bunch of other stuff things. In that cases the auto function might (will) not know what do you want to see and what you don't

JS
If I don't know how it works, I prefer not to turn it on.
 

Offline IDEngineer

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Auto is no different to an auto ranging DMM IMHO. Use it all the time. Easier than pissing around in the layered controls.
Interestingly Philips did analogue scopes with auto.
Same as the venerable Tek CROs.

Yes, and I use a calculator these days to do math too. But I understand the concepts behind what the calculator is doing. Pressing the equal button on a calculator, or the Auto button on a scope, doesn't teach you anything. The example from JS about "not so much for odd pulses like transmision line reflection or odd one offs events or one in a bunch of other stuff" is a perfect example of what we're talking about.

I like to actually understand my R&D equipment. But hey, maybe that's just me. Maybe Auto is good enough for design work these days, and I'm just an old fuddy-dud. (Speaking of equal buttons, my calculators don't have them because I use nothing but HP RPN. Two strikes against this old fuddy-dud?  :))
 

Offline Dubbie

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Not sure I have ever used the Auto button on my scope.
 

Offline tautech

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Not sure I have ever used the Auto button on my scope.
Yep, the only time I ever use it is with a new model that I've not seen before....like, I wonder how good this works ?

Blindly connecting a scope and pressing AutoSet is demonstrating plainly you have no idea of the signal you expect to see or have no idea how to operate a scope !
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Offline IDEngineer

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Not sure I have ever used the Auto button on my scope.
I don't think I've ever intentionally used an Auto button. And I hate it when I do accidentially hit the Auto button, because I then have to go back and set everything to what I actually needed.  :rant:  There's no "undo" button. And Auto's idea of what I want to see is almost always wrong.
 


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