oscilloscope

299 Articles

Active Probe Reaches 3 GHz

September 26, 2025 by 6 Comments

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

August 29, 2025 by 12 Comments

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

August 23, 2025 by 4 Comments

[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

July 8, 2025 by 1 Comment

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.

Tektronix TDS8000 banner

Repairing An Old Tektronix TDS8000 Scope

June 22, 2025 by 3 Comments

Over on his YouTube channel our hacker [CircuitValley] repairs an old TDS8000 scope.

The TDS8000 was manufactured by Tektronix circa 2001 and was also marketed as the CSA8000 Communications Signal Analyzer as well as the TDS8000 Digital Sampling Oscilloscope. Tektronix is no longer manufacturing and selling these scopes but the documentation is still available from their website, including the User Manual (268 page PDF), the Service Manual (198 page PDF), and some basic specs (in HTML).

You can do a lot of things with a TDS8000 scope but particularly its use case was Time-Domain Reflectometry (TDR). A TDR scope is the time-domain equivalent of a Vector Network Analyzer (VNA) which operates in the frequency-domain.

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Capturing Screenshots Using A Fake Printer

June 17, 2025 by 16 Comments

If you have very old pieces of analogue test equipment with CRTs on your bench, the chances are they will all have surprisingly similar surrounds to their screens. Back when they were made it was common to record oscilloscope screens with a Polaroid camera, that would have a front fitting for just this purpose.

More recent instruments are computerized so taking a screen shot should be easier, but that’s still not easy if the machine can’t save to a handy disk. Along comes [Tom] with a solution, to hook up a fake printer, and grab the screen from a print.

Old instruments come with a variety of ports, serial, IEE-488, or parallel, but they should usually have the ability to print a screen. Then capturing that is a case of capturing an interpreting the print data, be it ESC/P, PCL5, Postscript, or whatever. The linked page takes us through a variety of techniques, and should be of help to anyone who’s picked up a bargain in the flea market.

This isn’t the only time we’ve touched on the subject of bringing older computerized equipment into the present, we’ve also shown you a disk drive emulator.

Thanks [JohnU] for the tip.

Two Bits, Four Bits, A Twelve-bit Oscilloscope

June 10, 2025 by 4 Comments

Until recently, hobby-grade digital oscilloscopes were mostly, at most, 8-bit sampling. However, newer devices offer 12-bit conversion. Does it matter? Depends. [Kiss Analog] shows where a 12-bit scope may outperform an 8-bit one.

It may seem obvious, of course. When you store data in 8-bit resolution and zoom in on it, you simply have less resolution. However, seeing the difference on real data is enlightening.

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