A set of three stacked oscilloscopes is shown. The lower two oscilloscopes have screens and input pins visible, and the top oscilloscope is reversed, with a printed back plate visible.

A Higher-End Pico-Based Oscilloscope

Hackers have been building their own basic oscilloscopes out of inexpensive MCUs and cheap LCD screens for some years now, but microcontrollers have recently become fast enough to actually make such ‘scopes useful. [NJJ], for example, used a pair of Raspberry Pi Picos to build Picotronix, an extensible combined oscilloscope and logic analyzer.

This isn’t an open-source project, but it is quite well-documented, and the general design logic and workings of the device are freely available. The main board holds two Picos, one for data sampling and one to handle control, display, and external communication. The control unit is made out of stacked PCBs surrounded by a 3D-printed housing; the pinout diagrams printed on the back panel are a helpful touch. One interesting technique was to use a trimmed length of clear 3D printer filament as a light pipe for an indicator LED.

Even the protocol used to communicate between the Picos is documented; the datagrams are rather reminiscent of Ethernet frames, and can originate either from one of the Picos or from a host computer. This lets the control board operate as an automatic testing station reporting data over a wireless or USB-connected network. The display module is therefore optional hardware, and a variety of other boards (called picoPods) can be connected to the Picotronix control board. These include a faster ADC, adapters for various analog input spans, a differential analog input probe, a 12-bit logic state analyzer, and a DAC for signal generation.

If this project inspired you to make your own, we’ve also seen other Pico-based oscilloscopes before, including one that used a phone for the display.

A browser window is shown, in which a web page is displaying a green trace of a square wave.

A Compact, Browser-Based ESP32 Oscilloscope

An oscilloscope is usually the most sensitive, and arguably most versatile, tool on a hacker’s workbench, often taking billions of samples per second to produce an accurate and informative representation of a signal. This vast processing power, however, often goes well beyond the needs of the signals in question, at which point it makes sense to use a less powerful and expensive device, such as [MatAtBread]’s ESP32 oscilloscope.

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How Do The Normal People Survive?

It was one of those weeks last week at Hackaday’s home office. My mother-in-law handed me her favorite power bank and said “it’s not charging”. She had every expectation that I’ll open it up, desolder the weary pouch inside, scrounge a LiPo out of some corner of the basement, and have it back up and running before the weekend. And of course that’s what happened, although maybe it looks a little worse for wear because it was hard to open the sealed case without excessive force. Sorry about that!

Then on the weekend, I finally got fed up with the decomposing foam on the face seal on my FPV goggles. It was leaking light all over the place. Of course I could have bought a new seal, but then I’d have to wait a week or so for delivery. So I pulled the velcro backing off, tossed it in the bed scanner, pulled the image up in Inkscape, converted it to Gcode, and cut out a couple seals out of EVA foam on the laser. Not only are they essentially indestructible, but I was able to customize them a little bit, and the fit is now better than ever.

And then, one of our neighbors bought a new garage door fob, flipped the DIP switches into the right configuration, and couldn’t figure out why it wouldn’t open the garage door. Knock knock knock. Using the tried-and-true RF probe that everyone with a scope probe has sitting around, namely hooking the ground pin to the tip and putting the radio device in the loop, it was clear that the sense of the DIP switches was inverted from what it said in the instructions. That was a fun little puzzle.

It was the garage door opener that triggered me to think about how normal people would handle any of these situations. “How do the normies even get by?” were the exact words that went through my head. And let’s face it: we’re not entirely normal. Normal people don’t have a soldering setup just sitting around ready to get hot 24/7, or a scope to diagnose a garage door RF transmitter at the drop of a hat. But these things seem to happen to me all the time. How do the normal people survive? Maybe they all know someone with a scope?

I take it as my service to the world to be “that guy” for most of our friends and family, and I pretty much do it without complaint. “With great power” and all that. My wife is just about as gracious when she’s stuck debugging a parent’s Windows setup, so I’m not saying I’m the only saint in the world, either. Surely you have similar stories.

But last week it made me reflect on how good we’ve got it, and that does make me want to pay it forward a little bit. If you’re one of the people who can, try to help out those who can’t.

Active Probe Reaches 3 GHz

When you think of a scope probe, you usually think of what is basically a wire with a spring hook and an attenuator. Those are passive probes. [Kerry Wong] shows off a pre-release active probe that sidesteps some problems with those ordinary passive probes.

The trick is that passive probes have input capacitance that interferes with very high-frequency signals. They also tend to have less noise. Although the probe isn’t on the market yet, it is set to debut at a price lower than competitive probes. Still, be warned. The reason you don’t see them more often is that $1,000 is relatively inexpensive for an active probe.

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The (RF) Sniff Test

Sometimes the old tricks are the best. [Kevin] learned an old trick about using a ‘scope to sniff RF noise and pays it forward by sharing it in a recent video. He uses an oscilloscope. But does he need some special probe setup? Nope. He quickly makes a little RF pickup probe, and if you have a ‘scope, we’re pretty sure you can make one in a few seconds, too.

Of course, you can get probes made for that, and there are advantages to using them. But the quick trick of quickly and non-destructively modifying the existing probe to pick up RF means you always have a way to make these measurements.

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The Oscilloscope From 1943

[Thomas] comes up with some unusual gear. In his latest teardown and repair video, he has a vintage 1943 Danish oscilloscope,  a Radiometer OSG32 on the bench. It isn’t lightweight, and it certainly looks its age with a vintage cracked finish on the case. You can check out the tubes and high-voltage circuitry in the video below.

If you’ve only seen the inside of a modern scope, you’ll want to check this out with giant condensers (capacitors) and a slew of tubes. We love seeing the workmanship on these old chassis.

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DHO800 function generator

Budget Brilliance: DHO800 Function Generator

The Rigol oscilloscopes have a long history of modifications and hacks, and this latest from [Matthias] is an impressive addition; he’s been working on adding a function generator to the DHO800 line of scopes.

The DHO800 series offers many great features: it’s highly portable with a large 7-inch touchscreen, powered by USB-C, and includes plenty of other goodies. However, there’s room for enhancements. [Matthias] realized that while software mods exist to increase bandwidth or unlock logic analyzer functions, the hardware needed to implement the function generator—available in the more expensive DHO900 series—was missing.

To address this, he designed a daughterboard to serve as the function generator hardware, enabling features that software tweaks can unlock. His goal was to create an affordable, easy-to-produce, and easy-to-assemble interface board that fits in the space reserved for the official daughterboard in higher-end scopes.

Once the board is installed and the software is updated, the new functionality becomes available. [Matthias] clearly explains some limitations of his implementation. However, these shortcomings are outweighed by the tremendous value this mod provides. A 4-channel, 200 MHz oscilloscope with function generator capabilities for under $500 is a significant achievement. We love seeing these Rigol mods enhance tool functionality. Thanks, [Matthias], for sharing this project—great job bringing even more features to this popular scope.