MyE28.com

Who is using an oscilloscope and can you recommend one? 2 or 4 channel? Handheld or benchtop or a black box connected to a laptop?

I'm beginning to dive dive deeper into the details of Motronic while troubleshooting my 055 ECU, and thinking more and more about a 2022 standalone engine management in 2022. An oscilloscope would be a handy tool to make sure all the sensors that receive/generate variable signals are working as expected.

4 channel is useful, but generally you can get by with 2 channel. I think I've only ever used 4 channels for lab assignments, but it's very frustrating if you don't have all the channels you need.
I would get a benchtop personally, needing to have a laptop available and open can be annoying. I don't really trust handheld ones but that might just be superstition.
I own a couple older HP models and use tectronics a lot at school, the interfaces are different but either works well. Depends on what you like or are used to.
If I were going to buy something now, I'd get a 4 channel Rigol. They copy HP equipment and have really good performance for the price.

Thanks for the advice, Galahad. I wasn't warming to handheld but the PC-based is still a possibility. With a standalone system I'll have my laptop near the car anyway while I get the mapping and straight. I was leaning towards 4 channels and am now firmly in the 4-ch camp. I think that will come in handy--crank trigger, cam position, igniter pulse, injector pulse all at once might be handy. (Hmm... I'll have to figure out all the right probes for these.)

Certainly it'll be fun. I haven't used a o'scope since college engineering labs. It will be good to stretch those muscles again.

-Greg

If what you're doing is protocol decoding, reverse engineering, or some work that requires a long capture to figure something out, I'd recommend the laptop based ones (e.g. https://www.saleae.com/).

If you need to do some more basic work like look at the output of a hall effect sensor, then it's generally easier to just use a more traditional scope. The Rigol ones are pretty cost effective and for that kind of stuff, 50Mhz is plenty (https://www.amazon.com/Rigol-DS1054Z-Di ... B012938E76). Those do have protocol decoding too, but not the same sort of storage and mixed signal (digital and analog) that the laptop based ones do.

Thanks for the advice and recommendation. I will only be doing signal monitoring, sensor waveform checks, and DME troubleshooting. Nothing so advanced as trying to reverse engineer a digital system. I was wondering about the range so thank you for mentioning that 50MHz is sufficient. Looks like that Rigol 1000-series is the scope for me.

-Greg

Thanks for the advice and recommendation. I will only be doing signal monitoring, sensor waveform checks, and DME troubleshooting. Nothing so advanced as trying to reverse engineer a digital system. I was wondering about the range so thank you for mentioning that 50MHz is sufficient. Looks like that Rigol 1000-series is the scope for me.

-Greg

my snap on scope is great! does everything. auto and manual sets. has guided component testing built right in! no more trying to find pin out or wiring diagrams!
but it should have all that and more fore $2500....... -Paul

The big question with scopes is - how much do you want to spend?

I have 3 analog scopes that are 2 channel, 50 Mhz. I picked them up for around $25. They're good for general probing and sensor waveforms. If I destroy one in the garage, I won't cry. They are kinda big though with the CRT tube.
On the other hand, my serious scope is a RTB2004. That does protocol decoding and a lot more, but I'll never take that one outside as it cost more than my E28.

A good PC based scope is the pico-scope. It's in the $500 - $1k price range. You get a lot of bang for the buck with these and they're nice and small (i.e. portable) because the PC serves as the display. That's nice to have a big display.

I also have a scope similar to the Rigol (the Tektronics equivalent). I kinda wish I hadn't bought that one. Unless you really need to save waveforms, an analog scope will be cheaper and the waveforms will be crisp (not pixelated like those small digital scopes tend to be).

Good insight. Thank you.

THe serious digital diagnostic scopes do indeed require a substantial investment. I picked up a Rigol DS1074 (4 ch, 70 MHz) with a few probes from eBay that looks like it will serve well. Neither too large nor expensive to worry about garage use. Now I need to learn how to use it! The last time I turned one on was a few decades ago. Thank goodness nowadays we have YouTube instructional videos since my lab TA's office hours are long expired.

-Greg