If there is one instrument that makes an electronic engineer’s bench, it is the oscilloscope. The ability to track voltages in the time domain and measure their period and amplitude is one akin to a light in the darkness, it turns a mere tinkerer with circuits into one in command of them. Straightforward add-on circuits can transform a basic oscilloscope into a curve tracer, frequency response display, and much more, and modern oscilloscopes offer a dizzying array of useful measurement features unimaginable to engineers only a few years ago. And I need your help to pick a new one.
How do you measure the value of an unknown inductor? If you have an LCR bridge or meter, you are probably going to use that. If not, there are many different techniques you can use. All of them rely on the same thing my Algebra teacher Mr. Harder used to say back in the 1970’s: you have to use what you know to get what you don’t know.
[Ronald Dekker] must think the same way. He took a 50-ohm signal generator and a scope. He puts the signal output to about 20kHz and adjusts for 1V peak-to-peak on the scope. Then he puts the unknown inductor across the signal and adjusts the frequency (and only the frequency) for an output of 1/2 volt peak-to-peak.
We love a good multitool. There’s something seductive about knowing that if, for some reason, you need to saw down a tree on a moment’s notice, you have a tiny saw in your pocket. We also like electronic versions of the multitool: gadgets that serve a lot of purposes as you develop and debug hardware. One of the most polished-looking ones we’ve seen is [Phillip Schuster’s] Little Helper.
The open source gadget looks like an iPod (if an iPod had header pins sticking out of it). It has basic analog I/O capability, can generate PWM pulses, sniff I2C traffic, and do lots of other features. It is open source, so you can always add more capabilities if you need them.
Sometimes when a project is coming together, you need to cobble a tool together to get it completed. Whether it’s something very involved, like building a 3D printer to fabricate custom parts, or something relatively simple, like wiring a lightbulb and a battery together to create a simple continuity checker, we’ve all had to come up with something on the fly. Despite having access to an oscilloscope, [Brian] aka [schoolie] has come up with his own method for measuring PWM period and duty cycle without a scope, just in case there’s ever a PWM emergency!
The system he has come up with is so simple it’s borderline genius. The PWM signal in question is fed through a piezo speaker in parallel with a resistor. The output from the speaker is then sent to an FFT (fast fourier transform) app for Android devices, which produces a picture of a waveform. [schoolie] then opens the picture in MS Paint and uses the coordinates of the cursor and a little arithmetic to compute the period and the duty cycle.
For not using a scope, this method is pretty accurate, and only uses two discrete circuit components (the resistor and the speaker). If you’re ever in a pinch with PWM, this is sure to help, and be a whole lot cheaper than finding an oscilloscope!
[Chris] has been spending a lot of time in the wife’s sewing room lately, and things got pretty serious late last night as he hacked his shiny new Rigol DS1054Z to unlock the 1104Z capabilities lurking within.
The rumors are true, and ungoverning the software is as simple as looking up your serial number and knowing the right URL for generating a valid license. [Chris] ran into a dud site, but that’s the price of doing business in the shadowy parking garage basements of the interwebs. Once he knocked on the right door and uttered the secret word, however, he became the proud owner of 50MHz additional bandwidth, decoders for SPI, I²C, and RS-232, twice the storage depth, and all teh triggers that ship with the 1104Z.
Stick around for [Chris]’s video walk-through. Can’t rationalize the purchase even at the ridiculously low price point? Here’s one way to make it happen. You’ll laugh, you’ll cry, you’ll learn some French.
Want a new scope for your hacking pleasures? How about one that rings in at $3650? That price tag makes us cringe, which is why we’re working on our 1k word essay to win one. The Tektronix MSO2024B pictured above is the top scope in its family and there’s more than enough features to start the drool flowing. Need more motivation? Check out the demo/advertising video below which walks through an overview of what the scope has to offer.
The contest — sponsored by EETimes and Tektronix — seeks to reward the best story about fixing a product that was disappointing on delivery but awesome when you got done hacking on it. Your thousand words or less are due by October 26th along with a fifty word bio about yourself, with the winner announced on Halloween. Be warned, you must register an account to qualify But we hit their daily article viewing limit while writing this post so you may need to log in just to read about the contest. Or clear their cookies… we are a hacking website after all.
They’re only giving away one scope. So don’t put this one off. Start polishing your totally
bogus legit story about how you fixed something using mad engineering skills.
[Snypercat] makes no bones about the fact that she despises rats, and does everything in her power to keep them off her farm. We can’t blame her though – they spread disease, eat other animals’ food, and can get your farm shut down if there are too many running about. While most of us might hire an exterminator or set out a ton of traps, she chooses to take a far more hands-on approach, hunting down each and every one of those little buggers with an air rifle.
If you’ve ever gone rat hunting in the dark (and who hasn’t?), you know that it can be difficult to aim in the dead of night. Night vision scopes can be expensive, but [Snypercat] shows how you can make your own scope that gives you the added benefit of recording your kills along the way. She happened to have a Sony camcorder with built-in night vision capabilities, and with a bit of tweaking she was able to mount it on her rifle’s scope. An IR flashlight was mounted on the rifle as well, giving her enhanced visibility without spooking her prey.
Be sure to check out the pair of videos below to see how [Snypercat] attached the camcorder to the scope, along with how well it works in the field.