Expensive lab gear vs cheap and cheerful page 3 electricity for dummies amazon

I like the old scopes for mostly one reason – nostalgia. I admit it. I like the smell, I like the razor this traces, I like the sounds, I like the knobs, I like the performance, I like the repairability. However, I would not buy a Tek 547 (the Jim Williams model*) brand new for any reason. Do I have one? Of course, but I don’t use it for any serious work. I guess if I really needed a very small noise floor or to trigger on a very low level signal, something DSO’s still don’t do well, I could do that with the 547. It should be pointed out that the noise floor problem could be solved with a better ADC, but even the high-end scopes I’ve used appear to have a 8bit ADC with ~2mV/div being their lowest usable attenuation scale which equates to 78.125 uV resolution (at 10 vertical divisions) – which is probably okay for most applications, but is really not great for many applications (ADC, DAC, low-level analog, power supply ripple, precision test measurement, etc). Even a 10 bit could get you down to about 2uV/div which will make the noise floor issue nearly non-existent.**

I’m spoiled. I’ve worked for companies that aren’t afraid to purchase equipment. I have used 1GHz DSO’s from Tek of several generations. I hate them for several reasons, but primarily refresh rate, sample depth, and poor menu layout (In that order). I’d much rather use my 200MHz Keysight MSO. Tek simply hasn’t kept up with Keysight especially in refresh rate. Which means you get more bang for your buck with the Keysight scope. Despite the the corny name.

Now to answer the question at hand, does spending more on equipment result in better equipment? Yes – unequivocally yes. I have a friend that keeps trying to get me to buy one of the Rigol 2054Z (I think I got that right). I would argue that they offer more functionality than my old analog scopes and are probably worth the few hundred extra bucks if you’re a budding hobbyist. But really, I can get a decent refurbished Keysight MSO for only 3x the price of the Rigol. The quality of a Keysight product is top notch and I know I won’t be fighting my equipment much if at all. I don’t particularly enjoy troubleshooting my equipment – I enjoy troubleshooting my designs and old scopes. Is it expensive? Yes, but if you do things right, it will pay off in short order. I would not recommend the Keysight to a beginning hobbyist however. But to a home-based professional or an advanced hobbyist, it’s worth certainly worth the extra money IMHO, YMMV.

* – I think the 547 was Jim Williams favorite scope, although I believed he used the 556 a lot for producing images for his app notes primarily because he could get 8 traces on the display at the same timebase. The 547 is capable of 8 waveforms, but only of 4 signals, each at 2 different time bases, if I’m not mistaken (I have not actually done this myself – as I don’t have the proper 4 channel plug-in).

** – I also think the noise floor issue is a bit of a misnomer. The razor thin traces of these scopes were also a function of their reduced bandwidth. Most of these scopes only had 20-50MHz bandwidth. Ever done the calculation on Johnson noise at 200MHz on a 1Meg input impedance vs 20MHz?

Is it? Considering that the DS1054z is only $399 (or sometimes even less) for a 4Ch 50MHz scope with 12Mpts memory which with a simple ‘hack’ (where you enter a code generated on a website) can be unlocked to 100MHz, 24Mpts sample memory, serial decode and advanced triggers, while the cheapest offer from Keysight is the EDU variant of the DSO-X1000 Series, the $450 EDUX1002A which is a 50MHz 2Ch scope with laughable 100kpts memory and which includes two really poorly made passive probes. To get at a comparable level to the unlocked Rigol you’d have to spend almost $1k to end up with a 100MHz DSOX1102A which still only has 1Mpts (which thanks to Keysight’s MegaZoom ASIC leaves you with half of that or even less of usable memory depending on what you do) and only 2Ch.

The thing is that if your budget is $500 or less then the Rigol DS1054z is the most you can get for that amount of money. And because it has been on the market since 2014 it’s now a pretty mature instrument. Not sure what decent refurbished Keysight MSO you can get for $1200 but my guess is that this will be a DSOX2000 Series scope, which like all Keysight scopes in the entry-level market comes with tiny memory (1Mpts per channel, again in reality you’l often end up with half or even less than that thanks to the ASIC).

There’s no secret sauce in such low-end scopes, and the hardware quality that Rigol and Siglent push out is comparable to what you get from the big names (and was good enough for Keysight and LeCroy to put their names on kit manufactured by Rigol and Siglent). After all, Agilent taught Rigol how to design proper scopes, and LeCroy is doing the same for Siglent (which in return manufactures the WaveSurfer 3000 for them). What traditionally has been a problem with B-brands is firmware/software, but in case of the DS1054z most bugs have long been fixed (while Keysight’s new entry-level scope EDUX1000/DSOX1000 still seem to suffer from a few bugs), and both Rigol and Siglent have made improvements to their development processes.

If we’re talking about investing a notable sum, say $5k+ then yes, you’re better off with the big brands, and for that money you want big brand support and service. For $1500 or less, the B-brands like Rigol, Siglent or GW Instek can offer a better equipped product at a lower price than the big brands, all while offering at least standard service (i.e. warranty and repairs). And the savings can be invested in other stuff, i.e. better probing (which can be expensive, too).