Rigol 'Scope(s)

[mhennessy]

Originally Posted by G0HZU_JMR

I'm less impressed with the Hameg HM1004-3 even though it appears to be spotless and is probably only a few years old. I wouldn't recommend the 1004-3 unless it is very cheap although it is quite a small scope.
http://www.hameg.com/hm1004-3.0.html

From a quick look on-line, it seems OK to me. Let me know if you ever decide to part with it...

Originally Posted by pwdrive

As said earlier I don't want to go the second hand route if at all possible.

In fairness, you didn't say that:

Originally Posted by pwdrive

Not interested at the moment in boat anchor 'scopes.

The Philips and Hamegs mentioned most certainly are not boat anchors. It would be different if people were suggesting 500-series Tek monsters, but no-one has because of what you said initially.

So what exactly is wrong with second-hand?

Personally, I think you'd be mad to spend £300+ on a brand new analogue 'scope from a third-rate OEM when you could have a Tek, Hameg, Philips, Hitachi, Iwatsui, etc, for a fraction of that. These units were built to last so will have plenty of life left in them. Plenty of them on the auction sites (ignore the ones with "optimistic" starting prices, as will everyone else!), and I bet that a "wanted" ad here would yield a result. You might even persuade me to part with my Philips PM3215 if it avoids you making an expensive mistake

EDIT: This crossed with your last, but while I hear what you're saying, I've bought a lot of test gear second-hand, and rarely have problems - as I say, this stuff is built to last. Mostly, people are selling their old analogue 'scopes because they've brought shiny new Rigol DS1054Zs. Obviously, there is a risk associated with transit, but that's easy to deal with. And if you bought something from a forum member, it'll be a low-risk transaction - no-one here is planning to rip you off!

[ms660]

I'll probably go analog first then maybe later get a digital one to play around with as well, if I buy new then that decision will have been based on the bath tub curve.

Lawrence.

[mhennessy]

Baths were much bigger back then

[ms660]

Mark, don't tell that to m'new Landrover

Lawrence.

[G0HZU_JMR]

From a quick look on-line, it seems OK to me. Let me know if you ever decide to part with it...

The specs for the HM1004-3 look fine but it's the user interface that lets it down. It really is quite annoying. Some features are shared on the numerous little push buttons and you have to press and hold the button for a certain time to select different modes.

It looks like the x10/x1 scope probe selection and the AC/DC/GND features are all crammed onto one tiny cheap/plastic push button.

I've already forgotten which one requires the push + hold + select rather than rapid push/select. The whole scope is like this with too many features crammed into too few buttons. It's obviously some designer's darling at Hameg but to most users it's going to be a fiddly and annoying mess. It does have full control via RS-232 and maybe this is a blessing because this way you don't have to endure the hoplessly annoying front panel user interface.

It has an overall feeling of cheapness and flimsiness that reminds me of the old Philips scopes of the 1980s. Probably the only reason it hasn't had any broken buttons is because it has probably spent almost all of its 12 year life on a shelf in the graveyard stores at work. Nobody at work would use this scope and it must have been purchased for a specific task back in 2003/4 and then thrown into storage. It has what looks like an 04/03 Hameg datecode on the back even though it still looks unmarked. So I assume it is about 12 years old.

To add to the overall feeling of poor quality, the CH2 volt/div encoder only has about an 80% success rate in deciding which way I turn it. So sometimes it turns up the volts/div rather than down (or vice versa) It's hard to understand how something this simple could be designed so badly.

[gingpeakin]

I've got something over 20 scopes. Sad I know but the best and easiest to use one I have is an HP54600B 100MHz 2 channel thing. It's quiet, very easy to understand and has a lovely big display. Nothing stunning performance-wise as it only does 20M samples/s but Stewart of Reading have some at a very cheap £ 195. I don't have anything to do with them other than been a happy customer in the past.

Ging

[mhennessy]

HP made nice gear, and I'd bet the UI on that one is lovely. I also bet there are no bugs in the firmware!

Early sampling 'scopes like this were OK with repetitive signals. They use a technique called "equivalent time sampling", which builds up the samples in memory from multiple "sweeps". It works well. My old Fluke Combiscope does that - you can turn it off if you wish (which limits how fast the timebase can be set).

However, in "single-shot" mode, where you are capturing a non-repetitive signal, they are seriously compromised.

If you come from a lifetime of using analogue 'scopes, you might think "so what?", because by definition, most applications of an analogue 'scope are about viewing repetitive signals. And that's fair enough. But the more you use digital 'scopes, the more you realise that they really come into their own when you capture non-repetitive signals. Especially modern ones - even budget models like the Rigol 1054Z. I really love the way I can set the timebase to something like 1ms/div and capture a single sweep - and then zoom right in and examine the detail of the trace. For looking at serial data, it's invaluable. I take mine to work so we can analyse AES digital audio (our Tek DSOs aren't in the game here!); I use it for capturing I2C and SPI serial data streams; I use it to capture glitches in logic signals; or looking at the start-up of a power supply to make sure there is no overshoot. Recently I was working on a frequency counter that had a problem with the gate signal intermittently being the wrong width - but the duty cycle was so very low that an analogue 'scope couldn't display it, even with all the lights out. Piece of cake for the Rigol - which then allowed you to make an accurate measurement of the pulse width, which then led me to the right part of the circuitry at fault. Basically, a modern DSO allows you to do a whole range of new things with your 'scope that were either very difficult indeed, or frankly impossible.

Also, watch out for aliasing with the older digital 'scopes - with such limited sample memory, they changed the speed of the ADC to match the sweep time. Some of the less-good modern DSOs can also suffer from this. With the Rigol, it seems to be a non-issue. I'm sure it can be made to alias, but I've not managed it yet.

Finally, older (and many cheaper) DSOs lack intensity grading (or DPO, as Tek called it). This means that every sample is displayed at the same intensity. But on an analogue 'scope, the brightness of the trace varies according to the repetition rate of that part of the trace. Think about analogue video as an example. There is a lot of information in the relative brightness of a scope trace, and that is lost on a lot of DSOs. To be honest, I wouldn't have bought the Rigol 1054Z if it lacked this feature. Having lived with it for a while, I'd say that it's essential. This point is reinforced every time I use my Fluke Combiscope in digital mode (I really love my Combiscope, despite the limitations of the digital side - it's such a shame no-one makes a modern equivalent with the power of a present-day DSO)

[Brian R Pateman]

Four posts discussing postage of old 'scopes deleted as off topic.

Please stick to the subject.

[ms660]

Does anyone know if these "problems" have been sorted or is it a case of operator error?

https://www.youtube.com/watch?v=Mzo7332nhu4

Lawrence.

[evingar]

1. I don't have a problem with the probes supplied - Maybe he has a very cold house .

2. One of the trace colours is cyan, the other a much darker (Royal) blue. (to my eyes). Personally I find this a non issue, they are quite different.

3. He appears very heavy handed with the controls, sure if you "whizz" them up and down the shaft encoders won't keep up.

IMHO this scope is in no way "unusable" - sure, it may not have the response of a multi thousand Pound instrument ..... but it costs low hundreds.

Bottom line, yes, the 'scope has oddities and, yes, most of his criticisms have an element of truth about them. As they say, "you pays your money and you takes yer choice". I spent a long time looking round for a digital 'scope and IMHO nothing comes close to this one at this price point.

[ms660]

Later on he does another video praising the 'scopes upper frequency response.

I'll probably end up getting one at some point, but I wouldn't mind an analog job first, 'tis a bit like me and meters I used the Avo 8 a lot but for some jobs the digital one came in handy, you can lodge/balance it in/on a chassis when doing certain measurements under certain conditions

Lawrence

[Radio Wrangler]

Prepare to part with some serious cash, then. If you opt for a digital scope then you have to leave the basic models before you get enough sampling rate for their foibles to stop being problems. And as for new analogue scopes, it's no longer seen as a serious market by any of the reputable manufacturers.

As far as my scopes go, I'm happy with second-hand scopes. I took care to pick ones in good condition and they're proving pretty reliable. The new digital ones are heavily dependent on custom or short production lifetime devices. They aren't perfectly reliable either, and they can be found to be irreparable.

Another trick I played involves HP scopes. They look a bit plainer than Tek, but their CRTs are excellent, they meet their specs and most don't run fans but the really really great bit is that everyone and their granny knows that HP scopes are useless at triggering and so nobody wants the things. This makes them very cheap if not free. There was one family where it was difficult (well, very difficult) to set up the trigger circuits and the reputation has lived on long after the cause was fixed. Bargains! You don't need to keep it a secret because the reputation is so well entrenched that no-one will believe you.

David

[mhennessy]

Originally Posted by Radio Wrangler

Prepare to part with some serious cash, then. If you opt for a digital scope then you have to leave the basic models before you get enough sampling rate for their foibles to stop being problems.

Until recently, I would have said very similar things myself. Certainly, on the strength of a few Tek 'scopes, and a truly horrid bargain-basement Owon, I wouldn't have recommended digital 'scopes - from any manufacturer - to anyone.

But a lot has changed in the last few years. The sample rates are very high today. The Rigol always displays the current sample rate on the screen, and you can see that it's basically as high as possible, given the user settings. Certainly, I've yet to seen mine alias as yet (unlike my Philips/Fluke Combiscope). Obviously, there are a lot of settings you can change - settings that don't exist on an analogue scope, so a learning curve is part of the deal - that allow you to balance capture rate against amount of samples captured against how much zooming in you can do on a captured trace. I'm still getting my head around some of those...

About a year ago, I surprised some recent graduates, who had gone through their electronics degrees only using DSOs. At no point did anyone explain about aliasing. 30 seconds with a 1kHz sine wave oscillator and that hateful Owon completely blew their minds!

Originally Posted by Radio Wrangler

The new digital ones are heavily dependent on custom or short production lifetime devices. They aren't perfectly reliable either, and they can be found to be irreparable.

Yes, I agree with that. I doubt my Rigol will last the 40 years that my Telequipment has. They are basically disposable, like everything else today. Doesn't matter who makes them either.

However, surely this is a reason to not "prepare to part with some serious cash" then?

About 12 years back, I decided to treat myself to a new Fluke. Before long, I'd talked myself up the product range, falling hook, line and sinker for the marketing traps, and I bought a 189. I've never, ever used the functionality that differentiates the 189 from the cheaper 187, but it was a present to myself, and "I'm worth it", right?

But that DMM will outlive me.

Unlike the Rigol.

I looked at the next models up in the range, but decided really early on that I was not going to invest any more than absolutely necessary in what is essentially an unknown. OK, the previous model enjoyed a long life and I believe it's been reliable, but as you say, they are unrepairable.

The market has changed, and Rigol are to be congratulated for that. Until the previous 1052E, cheap DSOs were just that. I present the Owon, m'lud. Now, everyone has seriously raised their game, and most manufacturers have an entry-level 'scope that competes with the Rigol on price, functionality or price. No-one has quite managed to match them yet. I think you'd be pleasantly surprised at the functionality - and the build quality (if not the Fisher Price styling, perhaps!).

Of course, it's probably best not to mention how Rigol acquired a lot of their expertise. Not to a HP man, at least

Originally Posted by Radio Wrangler

Another trick I played involves HP scopes...<snip>

Agree with all that. I have a lovely 1740A that is almost A1, apart from (I think) a faulty hybrid module. Sadly I've yet to find one in over 6 years of searching. To avoid going OT, send me a PM if you're able to advise...

All the best,

Mark

[Radio Wrangler]

Yesterday, I'd just spent an hour fighting with a 2 GS/s Tek scope looking at a waveform that was a series of bursts of half-microsecond pulses. When the timebase was slowed down enough to see the timing of the bursts, the scope had decimated its samples enough to make some of the bursts appear part-amplitude, some to disappear in a pattern-y sort of way. Very disquieting as we were looking for a power supply instability issue that would have put slow AM on the bursts. We had to muck about with the timebase settings to get different bursts to show while others disappeared and to deduce that all were present and correct. The PRF within the burst was very close to the DSO sample rate clock and changing sample rate in integer ratios meant that what fell into the cracks between the samples still kept doing so, and the slow beat between the signal component and the sampling rates looked like what we were looking for. Murphy!

I think a Tek rep would have suggested one of their DPO range because they don't just dump unused samples.

When I have to explain sampling to people, I find everyone's familiar with the effect on the spokes of John Wayne's stage coach in the westerns, and the series of snapshots projected as a movie analogy works.... but for how long before no one in the wild knows of celluloid?

The only source of hybrids for 1740 is from another 1740. Fortunately, because no HP scope has ever triggered, they're cheap ;-)

All that is gold does not glitter,
Not all those who wander are lost,
The old that is strong does not wither,
Deep roots are not reached by the frost.

[Radio Wrangler]

Oh, the HP undersampling scopes (500MHz 'bandwidth' and a 20MS/s ADC) used to pseudo-randomly jitter the sampling clock, and used an analogue high resolution timing measurement against a non-jittered clock to get the correct X-position for each sample. This avoided a lot of alias problems, but still left the one-shot performance limited by 20MS/s

David

[ms660]

Just an update, I said earlier that the Rapid Electronics 40 Mhz analog jobie with frequency counter was a re badged B&K, it appears now that that it started life out as a Pintek CS 406.

The Tenma one sold by Farnell is still looking like a GW Instek jobie, the GOS 630FC

Here's two video's showing the GW Instek GOS 630FC, he shows the difference between that and a DSO (Agilent)

https://www.youtube.com/watch?v=JwldEg1mrfc

https://www.youtube.com/watch?v=xEV5QYS22Ac

Here's another GW Instek one showing the internals of the GOS 620, It's a 20Mhz 'scope but might be from the same series.

https://www.youtube.com/watch?v=Dfl_K5McOF8

I could handle the layout of that one servicing wise.

Lawrence.

[mhennessy]

Originally Posted by Radio Wrangler

Yesterday, I'd just spent an hour fighting with a 2 GS/s Tek scope looking at a waveform that was a series of bursts of half-microsecond pulses. When the timebase was slowed down enough to see the timing of the bursts, the scope had decimated its samples enough to make some of the bursts appear part-amplitude, some to disappear in a pattern-y sort of way. Very disquieting as we were looking for a power supply instability issue that would have put slow AM on the bursts. We had to muck about with the timebase settings to get different bursts to show while others disappeared and to deduce that all were present and correct. The PRF within the burst was very close to the DSO sample rate clock and changing sample rate in integer ratios meant that what fell into the cracks between the samples still kept doing so, and the slow beat between the signal component and the sampling rates looked like what we were looking for. Murphy!

That's a good example of why older DSOs are to be avoided - the lack of sample memory forcing the sample rate down for a given timebase setting. The Rigol has 24Mpts, which ain't bad for an entry-level 'scope!

We have a Tek TDS3054 at work that is a 5GS/s unit. Higher BW aside, it can't do a fraction of what the Rigol can because it only has 10kpts. Yes, 10k vs 24M! Makes a massive difference... The capture-zoom-pan functionality is actually really addictive, and makes things so much easier.

My ancient Fluke Combiscope is only 4kpts. The default is 512 pts, and if you select 4k, the update rate drops like a stone - it's better to use 512 with averaging. That's another parameter that has to be learnt with DSOs - if you need a fast update rate, you might need to shorten the sample memory or reduce the sample rate. Things were so much easier in the analogue days!

Pan and zoom isn't really available with the Combiscope - the main value of the digital mode is for the measurements. But I didn't buy it for the digital section - that was a "bonus" - I needed a 100MHz analogue 'scope and wasn't having any joy finding a spare hybrid for that 1740A

Folk who have bought these Rigols as their first DSO really have no idea of how bad things were just a fews years back. But hopefully these discussions are useful for highlighting the extra "layers" that need to be mastered on top of the basic operation they already know from the analogue days - I've yet to find an article or video that clearly explains the relationship between sample rate, update rate, memory depth and acquisition mode, and the more this thread goes on, I'm getting closer to writing it myself

Cheers,

Mark

[ms660]

Mark wrote: ""I've yet to find an article or video that clearly explains the relationship between sample rate, update rate, memory depth and acquisition mode, and the more this thread goes on, I'm getting closer to writing it myself""

That would be good, it's clear that analog 'scopes are almost at the end of their production so for a new 'scope then digital it will be once existing analog stocks have dried up.

Lawrence.

[jez_145]

Right,

Top Line:-

Just buy a Rigol DS1054Z and I emphasize that particular model number "DS1054Z".

I'm sure you won't be disappointed. I'm convinced there's no scope on the market that currently offers more bang for the buck.

I've had a few scopes in my time including an analogue Tektronix 465B with integral DM44 multimeter for around 20 years. I thought it was the bees knees - a great scope. Anyway, it started playing up and I then acquired a Hewlett Packard 54502A digital scope. Being my first experience with a DSO, this was a revelation to me. The ability to capture waveforms and the automated measurements were fabulous and, over 8 years or so, I did a lot of work with that scope both developing new circuits and fault finding.

Just before Christmas, I decided I'd like a new scope capable of doing FFT spectrum analysis and a few other things my 25 year old HP scope couldn't muster. I'd done a lot of research first and was seriously considering one of the Picoscope USB scopes which are very highly rated but quite pricey. However, Rigol was in the running - mainly due to the success of their earlier DS1052E model and the general price/performance of their instruments. Anyway, I took the plunge and shelled out 300 quid on the DS1054Z. This is the first time I've ever owned a brand new scope and I was not disappointed.

If you're moving to digital from analogue scopes for the first time I think you're in for a treat. Automated measurements are fantastic and save a lot of time. But there are loads of other useful features too which have been mentioned in earlier replies. Screen shots are useful if/when you need to document your findings. However, the DS1054Z also allows many other things to be saved too. In particular, the waveform memory can be dumped to internal or USB stick memory. This not only allows you to reload the waveform but also make further measurements on it, including FFT, in the absence of the original signal(s). Great if you want to do further analysis when you return to base. The main features I like about this scope are:-

- Automated measurements (more than you can shake a stick at !)
- Cursors (manual and auto) to do your own measurements or follow automated ones.
- Maths functions - FFT in particular.
- Ability to capture relatively long waveform sequences for detailed review.
- Plenty of trigger options - useful when fault finding.
- Colour display. Different colours for each channel makes a big difference.
- Ability to interface with other equipment and programs such as Matlab.
- General ease of use. Menus are no problem once you get the hang of them.
- It's easy to upgrade it to a 100MHz model with all the bells an whistles
if you ever need to. The hardware/firmware already supports these features. They
just need to be unlocked.

If you do buy a digital scope (or any other item of test equipment for that matter) I highly recommend that you take the time to run through all of its features and master its operation. When I bought my scope, I had a couple of weeks off work before Christmas and plenty of time to do just this. I'm now at the point where I can navigate my way around the instrument easily without having to think about it. Unlike, the PC/USB scopes, the DS1054Z has plenty of buttons and knobs to twirl which I find much easier than using a mouse on a PC. Plug it into the mains, connect your probes and away you go. No PC, wall warts, USB cables etc. to mess about with before you start work. Sure, any digital scope is going to present you with menus but these really are pretty easy to master and there's no other way you could access all the functionality offered by these instruments - unless you had an 6 foot wide front panel !

My first job with my new scope was to analyse the pulse sequence from an infra red remote control used with a digital audio recorder. This turned out to be pretty non-standard but the scope allowed an entire pulse sequence to be captured, scrolled through, zoomed into and measured accurately. My earlier HP scope didn't have enough memory to do this. From the measurements, I was then able to program a microcontroller to control the recorder - for use with a timer application I'm working on. Last weekend I used the scope to study the characteristics of three audio filters in an old, valve driven, Lowrey organ. This involved over 750 measurements which would have taken a very long time with an analogue scope. Incidentally, unlike typical USB scopes with a 20-30Vpp input limit, the DS1054Z inputs are rated at 300Vrms which can be useful when working on some vintage equipment and you don't have x100 probes to hand. On a related note, a friend of mine blew the front end on one channel of his expensive USB scope a couple of days ago, simply monitoring the voltage across a small 12 volt motor. That's back emf for you! We'll wait and see how much the repair bill is.

I'm so impressed with my new scope that I've also purchased Rigol's DG1062Z arbitrary waveform generator. Not cheap but another excellent piece of kit. I particularly wanted the ability to transfer waveforms captured on the scope to the generator memory for subsequent output. Unfortunately this "seamless integration feature" didn't work with the DS1054Z scope so I contacted the supplier (Rigol UK - Telonic Instruments). They were very helpful and, after investigation, advised me that a firmware update would be available within a month. 21 days later they let me know that a new release was available. I downloaded it and seconds later my generator was working fine with the scope. I think this says a lot Rigol's customer care and after sales service. I see a few contributors feel that these scopes are not repairable. Maybe they are, maybe they're not. In any case, they do have a 3 year guarantee and, at this price, they're probably a lot less than the cost of a typical repair on a big name brand.

Bottom Line:-

You've guessed it. A big thumbs up from me.

I still have an old 2 channel Tektronix 60MHz analogue scope. I haven't used it in a very long time. I doubt I'll ever use it again !


Jerry

[evingar]

Originally Posted by jez_145

Right,

I see a few contributors feel that these scopes are not repairable. Maybe they are, maybe they're not. In any case, they do have a 3 year guarantee and, at this price, they're probably a lot less than the cost of a typical repair on a big name brand.

On the EEV Blog "Tear down" :-

https://www.youtube.com/watch?v=kb9P1Am9aFU

It seems that the input amps are constructed with discrete transistors - Dave reckons this is to help towards keeping the cost down. It means (to my mind) that repair of the circuitry could be contemplated by anyone willing to take on simple SM rework. One would think that the repair here (probably the most vulnerable part of the instrument) would actually be cheaper than on a high end instrument that uses custom chips or other esoteric components that are harder to obtain or rework.

The other vulnerable part of any instrument is the power supply. The tear down shows this is well constructed and well cooled (in contrast to the "high end" Agilent 'scope at work , where the PSU is badly cooled and constructed on cheapo resin board - guess how I know !)

As this is newly introduced instrument only time will tell with respect to reliability but the omens are good and this was one reason I decided to purchase the 'scope.