Ask Slashdot: What's On Your Hardware Lab Bench? 215
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?"
thats silly (Score:5, Informative)
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
Re:thats silly (Score:5, Insightful)
Indeed. If you do not need a scope, then you do not do any real electronics. For some debugging, there is no replacement. Especially for gaining understanding, nothing can replace it. And yes, mine is not on so often either, but for some things there is no replacement and I need it. Also, with a nice digital scope, you can document things by placing screen-shots on the web or into documents.
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For a lot of low-bandwidth work with I/O controllers (like I2C buses, SPI peripherals running at low clock, etc) - get a BitScope. I have a network attached one and it's very convenient and inexpensive. They have a way of doing plugins, so it should be possible for instance to do a plugin to decode captures of I2C. The nice thing is it sits right on a desktop display, next to the ICE/JTAG debugger so you can easily monitor signals in parallel with watching board console output (for instance).
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Did I code up my interrupt handler on my $2 microcontroller on a $20 dev board? Is it the right polarity? Is the rise time OK with the on-board driver or do I need a buffer IC? The list goes on.
I understand your point but those aren't very good examples. A logic analyzer will tell you if your polarity is correct. Unless I misunderstood you your interrupt handler is also a "square" wave. And if your rise times are questionable at all, you still don't need a scope because the answer is yes.
I suppose I don't do real electronics (Score:5, Insightful)
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.
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Well, yes. And you need to be pretty disciplined with buffer caps and clean power traces/leads to avoid problems where a scope is the only thing that allows you to debug them efficiently. But, yes, pure digital, wide within spec electronics can be done without any measurement equipment.
Re:thats silly (Score:5, Informative)
For most digital work these days, you really just need a logic analyzer.
Unless your logic analyzer can show you ringing or capacitance / inductance problems on the digital signal lines, this is not really true. "Digital" signals on a circuit board are analog after all, and are subject to a lot of the same gremlins that plague an all analog circuit. This sort of thing doesn't always matter in a digital circuit, but you need a good scope to find them when they cause problems.
Re:thats silly (Score:5, Insightful)
Obviously, anyone designing electronics and building prototypes needs a scope. How else would you know what the ground plane looks like? Clean or noisy? Even a cheap 20-40MHz scope will show dirty signals as "fussy", and will allow identification of beat patters and cyclic issues... I suspect the OP doesn't actually do any board design, because if he did he'd be using his scopes and spending big bucks on really good ones.
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I suspect the OP doesn't actually do any board design, because if he did he'd be using his scopes and spending big bucks on really good ones.
I suspect you mean me (GP), not OP, because OP said you absolutely must have a scope.
I done lots of boards... but just one-offs, not designing for production. Never needed a scope for any of it.
Don't misunderstand me though: as I wrote earlier, a scope is very valuable and great to have, even if you're doing digital. I was just saying you can do an awful lot of digital work without one. In particular, I was referring to basement projects, nothing like motherboard design.
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All I do are "basement projects" but I've found a 100MHz digital scope amazingly useful, even for stuff that's pure digital. And in any case "modern electronics" doesn't mean exclusively digital. A great deal of stuff a modern hobbyist does will include analogue (basically interfacing with most things in the outside world).
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It's fine for simple two level digital logic. You can get away with it if you're just diagnosing stuff you attach to an Arduino.
But modern digital electronics has a LOT of analog components. Heck, one interface I have has two modes - low speed and high speed. When in low-speed mode, it's a differential signal that goes between
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Low-speed 1.8V and high-speed 0.5V LVDS mode, 800MHz... a MIPI-DSI display [wikipedia.org]? :-)
Re:thats silly (Score:5, Insightful)
If you do not need a scope, then you do not do any real electronics.
I would say that's just a bit over-broad. For most digital work these days, you really just need a logic analyzer.
Having said that, if you are doing just about anything but "pure" digital work, do do pretty much need a scope.
I don 't think its a bit over-broad. I've had a scope probe in one hand since about 1950, and while you guys with the logic analysers will eventually find the problem IF you know what the signatures are telling you, some old fart like me with a scope probe in one or both hands, will find the problem and have it fixed while you are still consulting the schematic and hooking up your 16 channel logic analyser.
If you do not understand ALL the physics behind how all this stuff works, you are just a wannabe. Out in the real world, we are checking electrolytic caps for ESR first, then cracked "cold" solder joints or corroded IC pins. When you think you are good enough, go sit for a C.E.T. test, pass it with a 99% correct score, and then spend the next 40 years convincing the folks who write the checks that you can indeed walk on water. BTDT, still doing it occasionally at 79.
Cheap or not, that's not the criteria ... (Score:3, Insightful)
... 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.
Re:thats silly (Score:5, Insightful)
If only I had mod points...
Trust me on this one, you can spend your days in simulations all you want, but that >100Gb/s board isn't going to work if you can't check your rails and the jitter on your reference clocks.
If all you do is program other people's boards/systems, and they have enough shelf life already to be certified to work properly, then a scope isn't useful.
If you want to be near the cutting edge, you shouldn't fly blind.
Oscilloscope and DMM (Score:2)
On my lab bench for 15 years:
Oscilloscope and Multimeter
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Add a good soldering iron, PSUs for at least two adjustable voltages and you can do almost anything.
An O'Scope (Score:5, Insightful)
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...]
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But then again I work on custom FPGA-based mixed signal boards and therefore have a lot of custom interfaces to debug... For a micro-controller based project running on Linear regulators?? Yeah you could probably get by with a Logic Analyzer, but that isn't going to cut it for more complicated stuff like my project at work or even the design of a Video card or the main board of your Laptop.
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It's very useful in many ways. Certainly for a lot of digital logic you can get away with one of the cheaper USB based mini scopes, but very often you need something a bit better when things aren't perfect and you need to see rise and fall of signals that aren't the ideal square (which none actually are). Ie, the signal is coming over a long cable which adds resistance and capacitance. But even those mini scopes are still real oscilloscopes in many ways and very useful for many normal activities; if you
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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:
And Garmin International: 300MHz is for yesteryear, today most engineers need at least 1GHz to get by in digital design
Agreed if you're doing low speed stuff. But a 1GHz scope won't even do what you need for e.g. SATA. Better go up a bit more. For example, at work I've been measuring a DDR3 bus trying to track down some issues - nothing short of ~3GHz would be sufficient for that. And next year we'll be working with some 10Gbps signals which means our minimum high speed scope requirement is going to be 25GHz => equivalent to buying a decent house in most of the country(1). Of course that's a work project and the post sou
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3rd tool: A thermal camera for when things go dreadfully wrong..
When things go dreadfully wrong? I though that's what the extra cell phone with the fire department and ambulance dispatcher on speed dial was for.
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See if logic signals are wiggling when your code tries to activate them
Measure frequency and amplitude of AC signals
Look for transients (using the trigger)
We have a nice Tektronix that also has 16 logic inputs. You also need a good DMM, we have a couple of the Fluke 280 series that can record for hours. That's ver nice whne we're trying to see how long a battery wil
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You may not be working with a signal that is in the 1 GHz range, but your rise/fall times may be in that range and if you want to verify that you meet timing requirements, you will need a higher speed scope.
Re:An O'Scope (Score:4, Funny)
African or European?
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The MHz number on the box is the bandwidth, not the sample rate. The sample rate is measured in samples per second (GSps). A 100MHz scope is probably adequate for analog signals up to 100MHz. However, if you're debugging a digital signal, you want a scope that has 3x the bandwidth of your signal's base frequency or more, because square waves are composed of the base frequency and an infinite number of harmonics. If you only have bandwidth for the base frequency, your square wave will be distorted into a sin
Adapters. Lots of them. (Score:5, Insightful)
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.
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Every conceivable adapter, gender-bender, splitter, and breakout box under the sun.
Just get one of these [youtube.com]
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Almost everything is smt these days, even home stuff, for me.
You can solder using a heat gun, and 2 sided pcbs are cheap these days in proto.
A 10k piece roll of 0402 resistors are ~$30; cut tape of any size is cheap from digikey, lol.
A scope is a required piece of equipment, from my viewpoint; I haven't used mine this month; maybe in july, but nothing else works when you need one.
Car audio amplifiers are one of the big things "friends" ask you to look at; showing them on the scope why it wasted their $1000
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Curiously, I went through the heat gun phase with SMD but I've returned to using a soldering iron, I've found I get less bridges (jumpers) that way and I do it much neater and faster.
hardware (Score:5, Insightful)
10" table saw
craftsman drill press
Makita battery charger
2 vise, 1 with soft jaws
3 levels
bottle opener
Re:hardware (Score:5, Funny)
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Bottle openers are unitaskers, and Alton Brown would be ashamed of you.
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Alton Brown is generally down on unitaskers, but even he uses some unitaskers.
I think the rule is: either a device must have multiple uses, or if it has a single use it must be a very important use, one you will actually use frequently enough to justify the unitasker.
In Alton's 10th anniversary special, he used his fire extinguisher (which he famously mentioned was his kitchen's only unitasker) to make a fruit smoothie.
I'll miss that show. Cooking for engineers, for sure.
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I used a guard rail as a bottle opener once. It worked great, except that after taking a sip of Coke, I realized the neck of the bottle came off with the cap. About one inch broke clean off, leaving a flat surface.
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Oscilloscope is difficult to use as a bottle opener if you want it to keep working. Similarly I would not use an RF spectrum analyzer for this purpose. These really should come with built in metal tabs that can be used for opening beverages.
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Convert that table saw to a ( metal ) lathe, and the drill to a mill and that's mine...
And don't forget the welder, grinder..
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Cyclotron.
(Come on guys, it's the 21st Century)
on the same theme... (Score:2)
10" cabinet saw with 72" rails
18" bandsaw
8" jointer
15" planer with carbide cutterhead
16-speed drill press
1.5HP dust collector with micron filtering
the usual set of small power tools
pretty decent set of hand tools (full-sized saws, joinery saws, hand planes, several sets of different kinds of chisels, rasps, files, mallets, etc)
power-tool oriented workbench along the wall
hand-tool workbench in the center (2.5" thick maple slab top with twin-screw face vice and quick-release end vise)
clamps going up to 8-foot
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It is worth noting at this point that, much to the disdain of the other posters who responded: A bottle opener can be very useful for things other than opening bottles. It is not a single-task implement.
My own bottle opener is made by Bic in France.
It can open bottles just fine.
It can warm hands.
It can shrink shrink tubing.
It can light tobacco or other smoking medium.
It can start fires, using its own built-in ignition source and integral fuel supply.
It can also be a source of butane (which can be a very u
ah so (Score:4, Funny)
you do use it, therefore it's dead.
I declare the Superbowl dead becasue I don't watch it anymore.
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Much like I really wish they'd play a World Series sometime during my lifetime. But in my world, it's only a World Series if the Cubs are in it. Otherwise it's like it doesn't even exist.
At least a dozen unfinished projects (Score:3)
I feel pretty good about that.
Much better than I ever could if I had no unfinished projects or any to start.
The beauty of a pile of parts and doo-dads scattered among various boxes is you always have something you can do if you have nothing else to do.
And there's always room for one more.
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Brother PT65 label maker (Score:2)
One of the best designed devices I have ever used. It is simple to use, ergonomic, doesn't waste tape (like the new ones) and just plain works.
It grants this wonderful ability to be organized and to know what is what and that is what keeps the rest of my lab working. Without a good label maker your lab is chaos abd unusable, something I have seen time and again for years.
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Yup!
I've found the absolute keys to keeping everything organized are:
- everything has a place
- that place is labeled
- that place is easy to get to (soon as you have boxes with other boxes on top, it becomes a hassle to put things back where they belong and the mess begins to grow).
I've practically got a whole wall covered in those little mini-drawer organizer dealies for all my odd bits and pieces. Keeps everything tidy.
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It grants this wonderful ability to be organized and to know what is what and that is what keeps the rest of my lab working.
I prefer self-organizing chaos. I use hashed buckets . . . Least Recently Used stuff sinks to the bottom of the buckets. Stuff I need a lot floats on top. Plus, I have a concept of RAID . . . since I can never find stuff, I have at least two of everything.
And when I really need to dig deep . . . it's like Christmas! I find all kinds of stuff that I never knew I had or used! Wow, I should try out that PCMCIA Token Ring card, or that USBVGA adapter cable!
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Personally, I go with a roll of masking tape and a sharpie.
No typing, no wrangling with menus to get special characters or to switch fonts. No vendor consumables lock-in.
essential (Score:2)
Essential a super good voltmeter , 2 signal generators , a dusl input scope , a frequency counter and a lesser voltmeter , but still 4 digits.
I will pass along that i have a small secondary scope for audio work. It's called a DSO 201 , it's the sixe of a small player , has a decent probe . Goes to 1 mhz. The kit fits in a shirt pocket : note that if you have one check the upgrade to the 4.22 series firmware , it works a lot better. So for audio it all fits in my small case with the computer that is very c
My desktop (Score:5, Informative)
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.
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side cutters (dikes in the US)
In my experience this tool's name depends more on occupation than geography.
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cheap chinese reflow oven
Yep. Highly recommended.
oven cheap chinese stencil jig
Caan you recommend one?
(and if I can finally persuade my wife) cheap chinese pick and place ,machine
Does such a thing exist??
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I have a $40 digital microscope [ebay.com] from eBay.
It's top heavy, so I inserted a rare earth magnet in the base and covered over with felt. It now solidly sticks to metal surfaces. It's also manual aim and manual focus, with no staging. This can be a pain for certain applications.
I use it for surface examination when I'm experimenting with process - such as processes for making PCBs. Here's an example [dropbox.com]. I take pics of the final result and create a LibreOffice word page describing the details of the process and how w
Scope (Score:2)
And would you tell someone trying to get into electronics that they need a scope?"
For anything intended for wireless use or that processes analog signals, yes, absolutely. But for a lot of things, it's just digital; you don't need a scope for that. You need what you have already. So it all comes down to what you want to build.
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For digital, these sorts of devices are very nice, portable, inexpensive:
http://www.saleae.com/ [saleae.com]
http://www.bitscope.com/ [bitscope.com]
It depends on what I'm working on... (Score:2)
Yes we have scopes (Score:2)
Multiple scopes: cheap ones for general purpose, fast (>3GHz (20gs/s) single shot) for looking at high speed electronics (would like a 10GHz singl eshot but $$).
RF synthesizers, spectrum analyzers, signal source analyzer, RF power meter, picosecond impulse genrator,
Power supplies DVMs, precision voltmeters, TDRs, temperature measurement, accelerometers,
Transient digitizers, with A-D / D-A and instrument control for automated testing
Fiber power meters, polarization controllers, detectors, transmitters
A l
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And an intern.
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Often 2 interns, sometimes 3. We make them use an RF spectrum analyzer that dates from the Cretaceous to teach them character. (and because our "good" spectrum analyzer still dates from the Pliocene and is usually busy). Despite our best efforts at abuse, the last set of interns managed to measure timing noise down to a few femtoseconds.
My bench inventory (Score:5, Interesting)
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...
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I'm curious: what kind of features would you recommend I look for in a used oscilloscope? I'm a rank amateur, learning electronics as I go. Mostly doing small Arduino-based stuff (doing a bonsai plant watering system right now, that involves some easy motor control and making a moisture meter), though I have some robotics-related ideas as well.
I'm not all that concerned about cost - it's a hobby so ROI doesn't really apply - but there's a bewildering array of features on scopes I've looked at, and I don't k
Scope usage (Score:4, Insightful)
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.
I have 3 'scopes in the home lab at the moment.. (Score:2)
From newest to oldest:
Rigol DS1052E--A "cheap and cheerful" Chinese import 50 MHz 2 channel DSO. A good general hobby scope, easily upgradeable to 100MHz bandwidth with a simple reflash of the firmware. Has a sizable following in the hardware hacker community because of the high "bang for the buck" factor.
Tektronix 7623: A 3-slot mainframe with 75 MHz bandwidth An 1969 vintage analog storage scope, which accepts various interchangeable plug in units to give a huge range of features. Actually has an on-scree
A 'scope is useful when it is. (Score:2)
> a used 20Mhz Oscilloscope
>a +/- 15V 1A Power supply i built with lm335s
>A signal generator i build with an XR2206 (going to replace with a bunch of op amps)
> A few multimeters of varying quality
> A few arduino clones (works great) and a generic PIC programmer (it's cheap and shit).
> enough antennas on my roof to make the neighbours complain. I'm looking to build a transceiver soon.
> A raspberry pi and a bunch
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Your approach is a tad wrong. You won't ever know if you need to use it - how would you? You're not an oracle. What you do is you use it first, and only then you have proof that everything is peachy. My bet is that you have very poor idea as to how your circuits really perform. Just because it "works" doesn't mean it's anywhere near being properly engineered. Just look at transition times on modern micro controllers and on the discrete logic chips that you're using. If your scope won't let you see those tra
oscilloscope (Score:2)
I still use my oscilloscope, signal generator with trigger, variable power supply quite a bit. I guess it really depends on what you're building. If it's anything to do with audio there's no escaping the need for an oscilloscope.
People who discount O-scopes..... (Score:2)
....Dont really know anything about electronics. I suggest getting into analog and learning the other 60% of electronics. It's actually not hard when you figure it out. (Hint: use math) and you blow the minds of kids learning it when you can blink an LED with 3 discreete parts instead of needing to program an arduino or picaxe.
I rarely use my scope..but (Score:2)
When I need it, there is no substitute
One of my favorite tricks when working on digital/analog hybrid circuits is to use the microprocessor to set an output pin, then use the signal to trigger a scope
I have debugged lots of tricky interrupt driven realtime stuff with this approach
But yeah, it gets turned on about once every two months
A logic analyzer doesn't count? (Score:2)
If you have a device that performs most of the same functions as a scope for digital systems, and you mostly work on digital systems, then no, you probably don't need a scope. But a scope is sufficient for most tasks, easy to acquire, and has more educational value. If you ever want to try anything analog, even if it's just scoping a power outlet, you'll need one.
I recommend an auto-ranging multimeter, a three-output power supply, and a super-cheap scope to start with. For embedded systems, don't forget tha
Tektronix 545 Scope (Score:2)
Keeps my shop warm during the winter.
I use the scope as a logic analyzer (Score:2)
Sure it doesn't do what a good logic analyzer does, but it's fast. Current project: trying to get an Ohaus digital scale's RS232 output talking via an FTDI serial-to-usb to my computer. Scope-to-computer works great. Computer-to-scope doesn't work at all. Hook up probes to the TX and RX lines and I can immediately see that something's going from minicom to the Ohaus, and the voltage is roughly what I'd expect. On RS232 that's a serious question, and one that most of the usb logic analyzers I've worked
On my bench, yep an oscilloscope. (Score:3)
Because of the work I do I have a collection of test gear I've accumulated over the years. The things which get the most use? The variable DC power supplies, the multimeters, and yes, the oscilloscope.
The oscilloscope occupies the spot right above where the target sits most of the time. I find it to be very useful to troubleshoot digital realm issues, including things which one would seem to think a logic analyzer would be perfect for. If I'm having a hard time getting two things to talk, say over an I2C bus, I reach for the scope first, since I can see whether or not the lines are toggling as expected. And if they're at the right voltages, and so on. I can also tell if the clock edges are correct and similar. This accounts for like 99% of the problems I run into that I need an external test instrument for.
Yes, I do have various logic analyzers. Two USB ones, a big one I'm about to sell on ebay, and a few more specialized ones (serial protocol analyzer, USB protocol analyzer). Most of the time they sit in their cases on the shelf.
-forrest
My workbench (Score:2)
What's on my workbench?
1) A PC running VNC
2) A datacenter full of servers loaded with chip design tools
3) A 6 billion dollar fabrication plant.
Scope is dead? Ha ha ha. (Score:2)
If you're serious about your work, you need a scope that gets down to device parasitics. If you're putting together a tiny little app-circuit-based switching power supply that's uses 0402 and 0603 passives with their puny parasitic inductances and capacitances, you better be able to see those effects or else. I'd say that for modern mixed-signal work you need at least 1GHz bandwidth, 10GHz sampling rate oscilloscope (or an analog equivalent, but there's like two to choose from). Anything active that's not b
My lab (Score:3)
First of all what I'm doing: I'm designing industrial embedded hardware, using funky data busses and high-resolution ADC's. I do all the hardware design, layout, prototype fabrication, and *all* firmware and host-side software. I'm pretty much a one-stop shop for this project (and the only engineer on it...). The hardware is all "slow" stuff at this point, with the fastest clock being the 32MHz driving the 8-bit microcontrollers scattered throughout the system.
Panorama of my office [omegacs.net]
First off I've got my computer in the "middle", nothing special except the monitor's on an arm to free up desk space. A second monitor to the right is used for debugging consoles etc. (and WoW). Several USB hubs are scattered around (some mounted) for use by both tools and the product under development.
To my left up on a shelf I have a (rented...) Agilent MSO-X 3014A scope, 4-channels plus 16 digital, unfortunately only the 100MHz version. I have a second-hand cheapy 5MHz signal generator next to that for occasional use (impedance checking etc). A simple Protek 3006B power supply (Fry's?) handles everything I can't run off USB 5V or from an LDO.
A Saleae Logic and Logic16 do quite a bit of work for me, and there's the occasional use of a BusPirate. An AVR-ISP MkII handles direct programming of the microcontrollers when possible, while the vast majority of my programming and test jigs are built around my own STK500v2 implementation multiplexed with serial debug.
To my immediate left is the main project space, while to my right is space for whatever projects crop up and don't have to have direct access to the scope.
In the window against the desk would be one or both cats.
To the far left is my soldering environment, which includes a regular temp-controlled soldering iron as well as an Aoyue Int968 hot-air soldering station (with its own soldering iron). A $25 toaster oven is used for reflowing most simple boards. Bins of loose parts cover the shelving above.
Behind me is a desk that holds a "proper" reflow oven, albeit the cheapo $300 unit from eBay, as well as a rework station of the kind used for XBox repairs (some of my boards have a *lot* of thermal mass that hot air alone can't handle). Reels upon reels of SMT parts are piled under the desk...
Lighting is provided by 2x 60/meter LED strips that side-fire to each side along the camera-window axis, plus an overhead Ikea quint-MR12 set over the main workspace when needed.
One word: Analog (Score:3)
just like the desktop computer... (Score:2)
Crappy scope (Score:2)
Had a bad week... (Score:3)
On this bench (Score:2)
Here is what I have at this very moment:
An oscilloscope, even
Just one tool (Score:3)
Re: (Score:2)
I have a Bambleweeny 57 Submeson Brain, an atomic vector plotter and a nice hot cup of tea.
Re: (Score:2)
I have a towel.
lots of gear (Score:2)
almost everything used from ebay:
a few fluke 45 DMMs (dual display, nice fluorescent)
tek scope 2225 (very low noise, analog, fanless scope)
pair of digital scopes (B&K and the famous hackable rigol).
many many lab PSUs (my faves are the old HP 6236 and the mostly unknown but amazing PDI (power designs) 2005 style dial-direct-reading unit)
many signal generators/function generators (a few hp's and an old japanese leader brand).
many freq. counters (fluke, hp).
oh, and the old simpson 260 VOM (gotta have some
The most important thing is experience! (Score:3)
I think the primary thing being left out of all the lists is the knowledge gained by experience. If you don't have it, nothing will replace just doing it yourself. Good tools are nice- but face it- EVERY SINGLE PIECE OF TEST EQUIPMENT LIES. Or maybe just doesn't tell you everything. Experience helps in figuring out what really matters. A 100 MHz analog scope is nice, but useless when it comes to a parasitic 1GHz oscillation. A logic analyzer is great, but misses a lot if two outputs are in contention.
The tools I use depend on the job I'm doing. Debugging serial comms? I love my Saleae. Looking at a fast edge? DSA602A.
That said, here's some of my vital lab equipment:
Saleae Logic
Tektronix DSA602A
Temperature controlled soldering Iron
Stereo Microscope
Credit Card
ebay
Scope is still critical (Score:2)
The scope still does everything. Other tools may have taken over some jobs, and may even be better at some things. But nothing can do as many jobs as the scope does, and I'm not even sure that a collection of tools can replace it entirely.
Also, building accessories for your scope is FUN. Tempted by cheap 8-channel logic probes? Don't buy one until after you've built a multiplexer for your scope. Other good projects include function generators, trigger modules (delays, holdoffs, strobes, logic, etc).
Buy
Re: (Score:2)
. I prefer the glossy paper/clothes iron toner transfer method, but direct milling is easier if you have a CNC minimill.
I've not heard of this method. Can you give any extra info?
There are several services that do group buys on short runs and small pieces. They assemble a variety of designs, send them out for fabication, then split them out and mail them back to you. I've used dorkbotpdx quite a few times, but there are plenty of others.
Unaffiliated, but I've used hackvana. Pretty good price, very small run
To See what is really happening (Score:3)
I am an old geezer and have been doing electronics from the days of vacuum tubes and point to point wiring to the current world of processors, ASIC's, and FPGA's and any time the analog world meets the digital I wouldn't trust any instrument more than a good scope. Your mileage may vary.
Not much at present. (Score:2)
A work-grade Matter Compiler, an electron microscope, and a few loupes and precision drivers. Oh, and some prototypical mediatrons I've been compiling that can share a bus when the sheaf is arranged like a book...
On my bench .. (Score:2)
HP 3312A Sig Gen (bought broken off *bay, fixed it)
HP 5385A Frequency Meter (bought broken off *bay, fixed it)
HP 54502A 400Mhz dual trace digital scope (bought broken off *bay, fixed it)
Homebrew GPIB adapter!
dual PSU (bought broken off *bay, fixed it)
DVM (bought broken off *bay, fixed it)
Open Logic Sniffer for a logic analyser
Multiple small USB-based toys
multiple small multimeters, going from tiny hand-hel
It's the software, stupid (Score:2)
As an engineer for 25 years, I do find that I use 'scopes less and less. That's not because 'scopes are less useful today. It's because the ratio of hardware effort to software effort on the typical project has gone from 10:1 to 1:10 in that same time frame. Building circuits out of discrete TTL on PCBs made using Bishop tape and writing 500 bytes of assembly code is (was) a different world than slapping a Raspberry Pi on a quick-turn PCB with an I/O driver chip and then firing up the C++ compiler. When you
What I have on my desk? (Score:2)
- Micro grinding machine;
- Solder iron;
- Lots of wires: copper, cotton, plastic, etc;
- Many sandpapers;
- Various types of scalpels;
- Lots of paints of many, many types;
- Magnifiers and retainers;
- Lead in different shapes and sizes;
- Scrap metals;
- Scraps of plastics (many types);
- many types of glues;
- A ship (1902 steel-hulled five-masted ship-rigged windjammer);
Does anyone have any idea what I do with all this?
Re: (Score:2)
What's on my workbench? A bunch of dead computers. The quality of name brand PC's has gone into the toilet. Commodity quality served up to the mass markets leaves very little quality to be found.
What you need is a good ol' Sun SparcStation with an old release of Red Hat Linux installed on it. No end of fun. Really cool little computers, too and greased lightning with a tiny kernel. :)
Re: (Score:2)
Re:A Bunch ... (Score:5, Interesting)
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
Re: A Bunch ... (Score:2)
Re: (Score:3)
LAs have become too much.
Often I want a lot of channels, but to capture diagnostic data specifically formatted for output to a diagnostic port on the chip. So I don't need a $100K Agilent mainframe LA setup. I just need a synchronous FIFO that can be triggered that a PC can read.
Since such things are not really out there, you just hack it together with an FPGA. So it's product+FPGA dev board+a few wires+a usb PC connection.
The DFX circuitry is all on chip. You just want to get at it.