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Ask Slashdot: What's On Your Hardware Lab Bench?
50000BTU_barbecue writes "I made a comment a few days ago in a story basically saying the oscilloscope is dead. While that's a bit dramatic, I've found that over the last 20 years my oscilloscopes have been 'on' less and less. Instead, I use a combination of judicious voltage measurements, a logic analyzer and a decent understanding of the documentation of the gadget I'm working on. Stuff is just more and more digital and microcontroller-based, or just so cheap yet incredibly integrated that there's no point in trying to work on it. (I'm thinking RC toys for example. Undocumented and very cheap. Doesn't work? Buy another.) While I still do old-school electronics like circuit-level troubleshooting (on old test gear), that's not where the majority of hobbyists seem to be. Yet one thing I keep hearing is how people want an oscilloscope to work on hardware. I think it's just not that necessary anymore. What I use most are two regulated DC lab supplies, a frequency counter, a USB logic analyzer, a USB I2C/SPI master, and a USB-RS-232 dongle. That covers a lot of modern electronics. I have two oscilloscopes, a 100MHz two-channel stand-alone USB unit and a 1960s analog plug-in-based mainframe that is a '70s hacker dream scope. But I rarely use them anymore. What equipment do hardware folks out there use the most? And would you tell someone trying to get into electronics that they need a scope?"
need a pullup? a scope will show you
have fighting drivers? insufficient path to ground? noise on the rails?
if you're doing anything aside from poking at other peoples stuff thats cheap and
disposable, you need a scope
If you're actually designing from scratch a new digital PCB, you can do without a lot of stuff but a 2GHz or faster O'scope is essential:
1) Debug of Switching Power Supplies [could get by with 100Mhz scope for this...]
2) Debug of high speed digital AC effects [line impendance, termination etc]
3) Verifying Setup / Hold of interface busses
4) Determining margin on variety of interfaces
Seriously. First tool a high speed scope... And Garmin International: 300MHz is for yesteryear, today most engineers need at least 1GHz to get by in digital design
2nd tool: a Good DMM
3rd tool: A thermal camera for when things go dreadfully wrong..
Other tools are gravy... [Though clearly a power supply is non-negotiable...]
Every conceivable adapter, gender-bender, splitter, and breakout box under the sun.
Guiding principle: For every connector form, there is an equal and opposite requirement.
Scruting the inscrutable for over 50 years.
10" table saw
craftsman drill press
Makita battery charger
2 vise, 1 with soft jaws
3 levels
bottle opener
I want to delete my account but Slashdot doesn't allow it.
you do use it, therefore it's dead.
I declare the Superbowl dead becasue I don't watch it anymore.
The Kruger Dunning explains most post on
On my office work bench:
Binocular microscope
soldering station
solder
flxes
large magnifying glass with light ring
project boxes full of SMD parts
tweezers
side cutters (dikes in the US)
scrap wire
storage scope/logic analyzer
power supply
In the other room:
cheap chinese reflow oven ,machine
cheap chinese stencil jig
(and if I can finally persuade my wife) cheap chinese pick and place
At this point I have to point out that almost all my best tools these days are cheap and from China, mostly bought off of aliexpress at prices maybe 10% of what I used to spend buying from the US - stuff I'd never ever have considered buying for myself 2-3 years ago. In this case being cheap and from China doesn't mean low quality or non-functional, quite the opposite.
Right behind a decent handheld DMM, a scope is about the second piece of bench gear I recommend to anyone. Old used digital scopes are so darn cheap anymore (my TDS340A that I've had for 18 years can now be had for $250-400 on eBay), and they really help you visualize what's going on in the circuit. I'd give up just about every other piece of real lab gear I own to keep my scope, because the rest is either for specific past projects, or is just nicer to work with, but could be substituted with lesser quality gear. There's no substitute for a decent scope in my opinion, but I do a lot of pure analog or serial stuff where being able to capture and stare at a waveform can go a long way towards finding a problem. Plus, all that digital eventually gets down to the real world, where ugly analog problems eventually rear their head again (slew rate, parasitics, transmission line uglies, etc.)
I'd bet I have my scope fired up 80% of the time that I'm not strictly working on firmware, and probably 20-30% of the time that I'm just working on code.
My main bench gear:
- Tektronix TDS340A scope
- HP 33401 bench DMM
- A couple various portable DMMs - one Fluke 87V, a couple cheapo Chinese, and a couple super cheapo Harbor Freight
- Saleae Logic16 logic analyzer (awesome tool, by the way...)
- Four old Lambda LLS lab power supplies
- Old HP 3310B function generator
- For soldering, a Hakko 936 iron, modified toaster oven for reflowing, and a hot air rework station
- a pile of other strippers, crimpers, pliers, screwdrivers, tweezers, magnifiers, and assorted hand tools including my favorite Xcelite MS-545-J cutters
- USBtinyISP for programming AVRs, Picstart 2 for programming PICs
- Mendelmax 3d printer for printing out parts and prototypes
- And a pile of other stuff to make the work more pleasant - my dev PC, a beer fridge, a TV, a Blu-ray player, a mythtv frontend box, a laser printer, bins of electrical and mechanical parts, datasheets I use frequently, etc.
I like all of the stuff, and wouldn't trade any of it, though I keep thinking about one of those new Agilent DSOX2024 scopes. I probably won't, though - my old Tek does well enough, and it has a great deal of sentimental value for all the years and projects we've done together. The only thing I'd really like is waveform capture on something that wasn't a 3.5" floppy...
I'm the author of Teensyduino, software for an Arduino compatible board.
I sometimes use my Agilent scope when developing or porting Arduino libraries. Sometimes I just want to check the relative timing of stuff, so I'll set a pin high or low at some point in the code, then capture with the scope to see if the code is taking a long time. Often it's surprising how fast, or how slow certain code can be, and pretty often it's relatively easy to discover and fix performance problems. You can do quite a lot by normal software debugging processes, but pretty much all those approaches involve running the code much slower. When you're debugging real-time code, like libraries that synthesize waveforms by bit-bashing or tricks with timers or DMA channels, there's really no substitute for a good scope.
But admittedly, this is a pretty narrow fringe. Most people probably don't do this sort of low-level coding.
PJRC: Electronic Projects, 8051 Microcontroller Tools
... when I am interested to know how one thing works
... when I just want to diagnose the inner-working of a gadget
I do not care how cheap that thing is, I'll power up my scopes
I do not care how cheap that thing is --- if I have to know I just have to know
I won't do the "oh, it's so cheap I'll buy a new one when this one conks", oh no, that's not the way I operate.
When my curiosity calls, I have to satisfy it.
Muchas Gracias, Señor Edward Snowden !
Heh. I've got an old SGI Octane running IRIX 6.5.30 UNIX. Great fun. With a buss that has ~3ms between any two I/O points and optical digital audio I/O, it's still quite useful for some audio recording/processing/storage tasks related to home recording studio work.
I also design and build vacuum tube guitar amplifiers, where my '70s-era two-channel analog 60mHz delayed-sweep Tektronix 453A 'scope still serves me well. It used to be used on avionics out on the tarmac in Nebraska and then Michigan, in winters & summers, baked and frozen, buried in snow and half-submerged in water, and has been blown hundreds of feet multiple times across the flightline tarmac from prop wash and jet exhaust and still functioned like a champ. Worst result was it lost some paint, gained some scuffs, and needed re-calibration. Not even the handle broke.
Many tens of thousands of years from now when humans are long gone and aliens are doing archaeological digs on Earth, they'll be shocked when they dig down, following a faint energy signal, only to find an old Tektronix 'scope still displaying a trace from when the tech left for the last time and forgot to turn it off. :)
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
but that's a fair accusation, because I don't really.
80-90% of things can be shipped off to software where it's delightfully easy to trace/probe/debug things, and you have a functional unit which is infinitely malleable. What you can't do in software most realistically ends up in an FPGA, where really you're just debugging your VHDL/Verilog, and the simulator is your new best friend for 80-90% of the cases. When the simulator is a lying piece of junk, 80-90% of the time all you need is a good logic analyzer...
But there's still that ~1% of the time where software and/or digital logic just didn't behave right. Something analog is either necessary (e.g. maybe you're doing something actually useful, like driving a motor, rather than just flipping bits), or analog is making your life miserable.
Even professionally, I've found a 2-channel 50 MHz analog scope to be a godsend in some cases; of course, I like my 4-channel 1GHz digital scope more :) If you end up interacting with anything real and physical, or if you you move beyond merely debugging black boxes and into building your own stuff, even a crappy scope can give you information you simply can't get any other way. Who cares if it is uncalibrated and wildly inaccurate if a surplus scope will still show you the shape of what is going on, with all of the noise and ringing and transient under-(and over-)voltages and double bounces and cross-talk and odd harmonics and wtf why was that capacitor in the wrong bin this RC constant is borked and yep that part's dead and oh shit bad solder job and all the other crap that makes me happy I get to spend most of my time in nice clean software?
If you're just putzing around, sure, a DMM will do ya. But if you're actually building something new (even something simple), you need a scope.