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Comment by tuetuopay | Hacker News Reader

Lots of sound advice, I especially like the mention of lead-free solder not being bad at all and the pencil soldering iron. Some surprises though:

- the multimeter should not be an afterthought like it seems to be in the article.

- I now tend to recommend buying a logic analyzer before buying an oscilloscope unless you're doing analog voodoo. Most of the time you're troubleshooting why is that darned peripheral over whatever bus is not reponding properly to your commands. Even a saleae clone is fine for most hobby work and won't break the bank if you're not happy (but please buy genuine ones if you can afford them!).

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I was a huge Saleae fan but with the last few projects I've been converted into a Digilent Analog Discovery 2 fan.

You get analog oscilloscope features, good enough for almost everything you will need on a typical project aside from RF or DRAM. Really good logic analyzer capabilities including protocol decoding and injection of signals - with analog waveform generation, digital protocols, and a small 5V voltage supply. Saleae still can't send a byte over UART.

And it's scriptable! Python, C++, and LabView. Again, something Logic can't do.

I'm not saying someone just getting started needs one, but if you've been in the business for a while and/or are working remote and need something on your bench, this can do almost everything in one go. The Pro model looks even more serious but I've never needed anything that powerful.

Yeah, those have been in my bucket list for a while, as they tick every box. Thanks for making me want one again!

I still think that Saleae clones are unbeatable for the price though and are the best investment someone getting started could want.

Yep - picked up one from eBay for $20 AUD. Fully compatible with their software. Amazing.

Hmm, but just a side note, one should not expect too much from it as a traditional analog scope. It's slow and its Achilles heel is the lack of an on board memory. It can neither cache more than 16k points, nor upload the samples through USB in real-time like a USB DAQ card. Today's sub-$1k Chinese scopes have few tens or hundreds of Mpts of sample memory, which turned out to be very helpful for my hobby.

Also it's quite overpriced now, unless one catch the $159 sale.

Slow? Perhaps. I don't know.

I was debugging a driver for those silly WS2812 RGB LEDs, the ones that are pretty picky about timing, and the AD2 could measure out edges in the 100 nSec range. Seemed pretty usable to me.

Recently being in the market for an oscilloscope, I was strongly considering the Digilent Analog Discovery 2, but I ended up going with the Siglent SDS1104X-E.

https://siglentna.com/digital-oscilloscopes/sds1000x-e-serie...

Just got it a day or so ago but am so far really impressed with it. It should be good until I hit some point where I need to upgrade. At that point, I should have a better idea of the exact features I need, although it was tempting to pre-upgrade to the SDS2000 series. The Rigol's seem great, especially the MSO5000 series with dedicated controls per channel, but I've seen a lot of complaints about noise levels and preferred the more featured and cheaper Siglent.

I'll probably get an Analog Discovery 2 or a Digital Discovery if I need some more digital logic stuff, although the Siglent can do some decoding.

I really dislike my Siglent. The measurement UI is horrible and the probes are iffy. I’m still mostly using a relatively ancient Agilent 546xx (can’t remember which model) and some decent Keysight probes and will probably sell the Siglent.

The Rigol UI is painfully slow. I didn’t buy one because of that.

I actually have the opposite feeling.

I have used quite a few low-end scopes at work, a new Siglent, Agilent DSO7034A, Tek DPO3054, some Tek TBS2000, some RS RTB2 and Keysight 3034T. I prefer the RS if my boss is paying for it, but there isn't too much to complain about the Siglent.

The DSO7000 series (and those other VxWorks infiniums) are the direct successor of 546xx, it always work and it's nice to have a few Mpts of memory. But the feature set is quite limited, no intensity grading display and the FFT looks so poor compared with more modern scopes. I'd be happy to replace that DSO7034A on our bench with a Siglent.

The KS3000T also have a laughably slow UI. The touch screen is supposed to make cursor measurements easier, but it doesn't. If one VNC to it (yes, running Windows CE), one can get miserably 1 fps.

That's a fair evaluation. I mostly do RF stuff these days (SA + VNA) so the scope use cases are fairly basic. Mine's a 54642D so 500MHz + LA. I don't want to put down at least 50x what I paid for it ($100 broken - $10 fix) for a new scope. The Siglent fills the feature gap and but I don't like it.

+1 for getting a LA for digital work. I started with a Saleae clone (dirt cheap and works), and loved it so much that I bought a Logic 8. They have a 50% discount for hobbyists which brought it down to an affordable luxury for me.

https://blog.saleae.com/saleae-discounts/

I just bought one of these and then realized the 10+ year old linksys router I wanted to reverse engineer uses an 80 mhz SPI bus, which is too fast for the entry level Salaea. Nice hardware if it works for your use case though.

For these (relatively) high speed serial interface, a scope with protocol decoding is actually more suitable.

Would you recommend something like a Rigol DS1104Z?

If it's really 80M, DS1104Z is still not fast enough. Maybe something with like 350M BW is required.

Also note that many modern scopes have software bandwidth limitation, and many of them are hackable. Rigol and Siglent are famous for making their scopes trivially hackable, that's a marketing point, but some Tek and Keysight's also.

The DS1104Z has a MSO option: if you add the RPL1116 logic probes, you can sample 8 channels at 1GSa/s, or 16 ch at 500MSa/s. That should be easily capable of capturing 80MHz SPI.

The downside to using a scope is it's much clunkier than using a LA on a PC. The decoder option it will give you the data, but if you're doing more than a handful of bytes, it gets tedious to scroll through hex dumps on screen and manually copying out the parts you want.

Saleae's software is delightful for this on their hardware. However, Sigrok is a decent alternative which supports a lot of devices. That includes the DS1000Z series, though I don't know if that includes the logic inputs. The OP might want to check them out.

https://sigrok.org/wiki/Supported_hardware

I spent around $500 for a used Logic Pro 16 and it’s easily my most valuable purchase. Even for analog voodoo it’s good enough most of the time as I’m debugging logic level signals. I have a very capable Tek scope with all the bells and whistles unlocked but only plug it in if I’m working at higher voltages than the saleae can handle.

Far too expensive.

Someone just setting up an elab is WAY better off buying one of the ubiquitous Chinesium 24MHz 8-channel USB logic analyzers. In addition, a newbie is way more likely to "just try it out" if the thing they can destroy is only $10.

I have lots of really nice equipment, but even I will pull the cheapass logic analyzers out when I'm doing something that has the possibility of destroying my more expensive stuff.

24MHz 8-ch is a bit insufficient for debugging most of real stuff which is when the real fun is.

Also IMO logical analyser and scope are two things where you want to spend money when you are starting with electronics. This is how you are going to learn stuff and how you are going to debug anything you do. You need good scope and analyser EXACTLY because you are a newb.

I am personally using DSLogic U3Pro16 which was $300 when I bought it and I can highly recommend it.

> 24MHz 8-ch is a bit insufficient for debugging most of real stuff which is when the real fun is.

And by that point you'll not be a newbie anymore and know you've outgrown your chinesium. But for most tasks, it is plenty enough. It's amazing how much you can do with so little.

> You need good scope and analyser EXACTLY because you are a newb.

I highly disagree. You need decent enough ones, not good ones. Want to decode that uart? Wanna know why that adafruit I²C sensor is not responding? Why this SPI thing sends garbled data? The logic analyzer will be the biggest help when working with digital electronics, which is what most people get started with.

You need good scope and analyser EXACTLY because you are a newb.

I have my doubts about this. I believe that many beginners will experience the "I'm scared to use this" effect if they buy something too "nice" (read: expensive). Hell, to this day, I still use my Rigol DS-1102e first for most things, in favor of breaking out the "nice" oscilloscope, because I have that faint murmuring of "if you're going to fry a scope, fry the cheap one" in the back of my head.

The cheapies are great. I will say that, of the modern USB based analyzers, DSLogic is the only affordable one with a compensation network in the probes similar to what benchtop analyzers used to have, shielded leads, and configurable comparator voltage. It isn't worth paying $500+ for something where they just wing it on the probe interface.

Depends on what just setting up means. Someone tinkering with their first ESP32? Sure have at it with Chinesium. If you're getting more serious I'd say my $500 Saleae is a more valuable purchase than a $350 rigol scope recommended in the article.

eeh the logic analyzer is nice when things work well enough, but many times I get nonsensical results from the LA and I have to go back to the scope to figure out what's exactly is going wrong.

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