I love analog scopes. I even have, somewhere, a massive Tektronix storage scope which “works” but I sure wouldn’t want to try to use it if I had anything modern to choose.I have to disagree with the previous posters here, and strongly recommend you don't get an analog scope. Seriously. Just don't. Let me tell you why:
My first scope was an analog scope. It was a Tek. It failed shortly after I bought it. Luckily I was able to fix it (bad op amp). Fortunately it was not that difficult to do the actual repair. The chip was in a socket and it was in a place that was easily accessible. But that experience scared me. I saw how compact everything was. It is actually kind of fascinating that a group of engineers could design such a thing all before modern computers and design software.I have to disagree with some of the previous posters here, and strongly recommend you don't get an analog scope. Seriously. Just don't.
Let me tell you why:
First, any analog scope you can buy today will very likely be 25+ years old, a time after which it has long passed the zenith of its natural service life, i.e. it's very likely to fail on you sooner rather than later. If it breaks then you need at least another working scope to fix it. That of course assumes that there are no unobtainium parts in it, which many scopes have. The fact that switches are mechanical (which makes them less reliable) and that it's usually full fo ageing and drifting analog components isn't helpful either.
Then there's functionality. An analog scope shows you the signal in (somewhat) real-time. Unless you get one of the more rare analog scopes with storage tube (which comes with its own set of problems) then you have no way to record and store any events, short of you sitting in front of it with a photo camera (and then hope you press the shutter at the right time). On most analog scopesyYou get no measurement facilities (although some better ones had cursors with read-outs), you don't et any analysis tools like math or FFT, you don't get to decode serial data busses, and a range of other things that are common in digital scopes for over 2 decades now.
The worst thing however is that an analog scope teaches you outdated methodology which when used with a modern digital scope can be inefficient or even counterproductive. Unless you want to work as a curator of antique test equipment you should learn how to handle current equipment correctly, not yesteryear's.
Don't get me wrong, there's nothing against getting an analog scope as curiosity or collectors item, but even then it should be free or really really cheap (i.e. <50 bucks, everything else is money flushed down the drain). Still, spending big money on an antique boat anchor is ludicrous.
Made me laugh. That $50 must include free shipping, right?I echo @Wuerstchenhund and @Yaakov's comments on the matter, with one caveat: if you can get an analog scope in working condition for free or a very low price (<$50), then it is a good start - the problem is evaluating if it is in good working order.
Even if it is, you still end up memorizing outdated methodology.I echo @Wuerstchenhund and @Yaakov's comments on the matter, with one caveat: if you can get an analog scope in working condition for free or a very low price (<$50), then it is a good start - the problem is evaluating if it is in good working order.
I agree, a 2nd hand Rigol DS1000E Series could be an option if you can find one cheap (<$100), it's very limited in functionality but it's still a better buy than an analog scope. The same is true for Siglent old SDS1000CML/CNL Series (<$150).Another option that is still quite usable and, if you can get for a very cheap price (<$100), is the Rigol DS1052E, which has more modest features when compared to the other two models mentioned above but it is quite a solid product. I had one and it is quite a great beginner's digital oscilloscope on a budget.
Actually, this isn't true. I fixed a number of DSOs myself, and there are lots of people on the various forums repairing DSOs. It's not necessarily any more difficult than fixing an old analog clunker, just that some of the failures are different. Most of the problems in DSOs come from leaky caps, expiring backup batteries, defective encoders or a dim/dead backlight, usually all fixable with some soldering skills. But mostly, DSOs are very reliable, even the cheaper ones from Rigol and Siglent, all much more so than any analog scope.The bad news about a digital scope is that you will likely not able to fix it if it dies.
I think that Keysight entry level scopes like EDUX1002A is good choice if you want top brand and you are ok with 50Mhz.
https://www.amazon.com/KEYSIGHT-EDUX1002A-InfiniiVision-Digital-Oscilloscope/dp/B06XCY9YHZ
Ah yes, the 7000 Series of modular scopes. When they were current back in the days we had lots of them in various test sets, and while they were highly flexible they also were by far the most unreliable test instrument we had. The frames were fine but some of the modules spent more time in repair than in the scope.I would go with the Rigol, Siglent recommendations.
But I keep around, and occasionally use, a Tek 7000 mainframe scope.
It bridges analog to DSO, but more importantly for me its specialized plugins
make it a broad based instrument. Some of the plugins are -
1) uV differential preamp with selectable hi/lo cutoff filter
2) Several spectrum analyzer plugins (pricey on ebay, but amateur radio flea markets
I have gotten some very good deals), 70 db noise floor kind of capability. Audio thru
18 Ghz versions. 60 Ghz with external mixer.
3) Sampling plugins to 10 Ghz
4) Real time straight analog version to 1 Ghz
5) Basic curve tracer
6) Optical plugin
To name a few.
So if you can get it cheap worthwhile to keep around. But consider this secondary.
Well, free shipping or local, that would be my recommendation.Made me laugh. That $50 must include free shipping, right?
Wuerst, by that logic why have grids at all? Why actually show the waveform if you are only interested in the parameters? In my experience with new hires, dexterity with the menus and options is something much easier learned than actually having the critical thinking about a measurement gained by counting graticule subdivisions or using cursors. As the old saying goes: there are lies, damn lies, statistics and what is displayed in the screen of your oscilloscope.It got better now, but there was a time when a number of applicants for our junior EE positions were unable to use a DSO properly because the college they went to still clinged to their analog scopes. One of the aptitude test we used was sitting the applicant in front of a digital scope (usually an Agilent/Keysight, as they are the most widespread DSOs) which is showing a modestly complex waveform and asking them to provide the signal parameters. You could instantly recognize those that were taught on analog scopes because they would start looking for cursors or start counting bars in the graticule, instead of just using the measurement suite.
Our experience with them quite different than yours in terms of reliability.Ah yes, the 7000 Series of modular scopes. When they were current back in the days we had lots of them in various test sets, and while they were highly flexible they also were by far the most unreliable test instrument we had. The frames were fine but some of the modules spent more time in repair than in the scope.
But yes, you can definitely get a lot of functionality with the Tek 7000 Series analog scope. Most scope frames are pretty cheap as are the modules, although some of the more rare ones are still very pricey, as they seem to be picked up by collectors.
The Rigol and Siglent are, as you say, also “way outside what a beginner wants anyways”, But then that clearly states you and I know what the beginner wanted. That’s a stretch.But leaving aside for a second that most of the functionality on the list is way outside what a beginner wants anyways, the fact that the modules all go into an analog scope frame alone limits their usefulness.
The 7000 has measurement capability, 7854 extensive. And various plugins/frames allow for storage and digitization.For example, uV sensitivity is great, but it doesn't change the fact that the scope is still devoid of any of the very useful functionality of a DSO, like the one-shot capability, the storage, the ability to save a screenshot or waveform data, or the measurement, analysis and math tools. So while the plugin might help you to see a signal, it still can't be processed further as on a DSO.
The 7L18 have digital storage, as do several others. Basic spectral measurements also an inherent feature as well. I would suggest you read the operators manual before posting on this any further,. As well as the 7854 manual. I will have to read the 7L18 manual to look at sweep capabilities.Or the spectrum analyzer plugins. A technical marvel in the '70s. In today's standards, with plugins like the 7L18 you get a wonky spectrum analyzer with a truly horrible RF performance and inability to sweep through the full BW. And as before, the drawbacks of the analog scope frame, i.e. the absence of any analysis and real sensible storage function still remains.
And there is really not much use for a 10GHz sampling plugin, which is only useful for perfectly repetative waveforms or TDR, in an analog scope frame, and this not only because the limitations of the analog scope frame are also valid here. There isn't a lot of use for sampling scopes these days, and where there is there's also the necessity to perform some further analysis on the signal (i.e. jitter). Which you can't do on a 7000 Series analog scope.
Wrong again for all the prior reasons.The same is true for optical signals.
Curve tracer = device curve tracer like NPN, PNP, MOSFET, JFET…..that takes specific power capabilities and forcing functions not in typical DSOs.Every better DSO can act as a curve tracer, and scopes like the Siglent SDS1000X-E already come with a Bode plot function. Not to 1GHz, but for that you'd need a 7104 scope frame, which sometimes fetch up to $600 or more alone.
As stated in the post you have to buy carefully. As far as cost if I had to buy the equivalent of every specialized plugin in other instruments I would be able to pay off the debt of the EU…..In addition, while most 7000 Series plugins are somewhat cheap (although prices seem to be increasing), one or two 7000 scopes with all these plugins will still cost you a not insignificant amount of money, and you are still left with antiques that perform shoddily in most of today's applications, even when compared with gear from the '90s.
Not going to argue with you about utility of the 7A22 or the costs to buy active diff probes, I have them both, use them both.If you work with uV level signals then a pre-amp or an active differential probe together with a DSO with active probe interface will do what you need. And when buying 2nd hand even without breaking the bank.
I have 3 plugins, total of all 3 were $ 120. And I have HP, but as you say its probably wonky even though they all get frequent use. Challenge for you, go buy the range of capabilities and tell me what you purchased.If you really need a spectrum analyzer then there are many standalone units that easily outperform the wonky SA plugins for the 7000 Series, even new low-cost units like the Siglent SSA-X or the Rigol DSA800. On the 2nd hand market there are many SAs from HP, Anritsu, R&S or Advantek that offer solid RF performance with good analysis capabilities for not too much money. Not necessarily to 18GHz, but if you really need 18GHz BW then you will have the money to pay for it as pretty much everything from cables to attenuators and adapters is very expensive if rated to that frequency.
I have an HP54100 and think it sucks. About to literally dump it. I have one of their storage portables. It sucks. But did what I needed at the time.If you really need a sampling scope or TDR, the HP 54120A/B+54121T digitizing scopes can often be found for very little money and can even go to 20GHz, all while offering many of the advantages of a digital platform.
Yes, a nations GDP spent on test equipment will bring you everything. Clearly the type of design work and specifications drive test equipment needs. A 100 – 200 Mhz cheapy Rigol or Siglent is fine for some,. Not for others. A LeCroy LabMaster 10 Zi just barely adequate for others at $ 150 K, just the basics.So yes, the Tek 7000 Series of modular analog scopes may look like a good low-cost solution for many more niche tasks, however if you want to do serious work then the poor performance and the many limitations of that antique platform just won't cut it, and after having to spend money for a working chassis, all the plugins and maybe some spares the financial side may no longer look that attractive, too.
+1Well, free shipping or local, that would be my recommendation.
Wuerst, by that logic why have grids at all? Why actually show the waveform if you are only interested in the parameters? In my experience with new hires, dexterity with the menus and options is something much easier learned than actually having the critical thinking about a measurement gained by counting graticule subdivisions or using cursors. As the old saying goes: there are lies, damn lies, statistics and what is displayed in the screen of your oscilloscope.
Despite I agree with your assessment that we need to critically think about how we learn and teach more modern techniques and tools, I wouldn't go as far as saying this skill or its tools are useless as a lobotomy. It is a complementary skill that will still save your bacon in many situations. Obviously that, with such analog background, there is also a ramp to be learned to teach the discrete numeric approach of modern data acquisition systems.
The DSOX1102G is a nice scope for the money.Not that it's a bad scope (we have a few DSOX1102G which are the 'grown up' model of that scope and which we got for free when buying other Keysight gear), but with the Keysight DSO-X1000/EDUX1000 you are paying through the nosie for an underspec'd low end scope with the Keysight name on it.