Fixing A Malfunctioning Keithley Model 179 Digital Multimeter

February 2, 2024 by 7 Comments

Inspired by electronics repair videos on YouTube, [Steven Leibson] recently found himself hunting down something to fix on eBay. This ‘something’ ended up being a  certified classic: a Keithley Model 179 digital multimeter from 1978. Listed as non-functional, the unit arrived at his door for less than $50. There weren’t any exciting pops or smoke when he powered it on, but the display seemed to be showing nothing but random nonsense.

The Keithley Model 179 multimeter has a convenient calibration sequence printed on its electrostatic shield cover and a deadly exposed ac line fuse in the upper left part of the photo. (Image credit: Steven Leibson)
The meter has a convenient calibration sequence printed on its electrostatic shield cover and a deadly exposed AC line fuse in the upper left part of the photo.

Ultimately reviving this little piece of history was quite simple, with the main issue turning out to be a dodgy inter-board connector between the main and display boards. After admiring an old repair attempt made on the component, he removed both the male and female connectors, replacing them with new ones.

This uncovered issues with the PCB, as the FR4 material and the traces on it had begun to delaminate, probably due to the old adhesive giving up due to age. With pretty low trace density this wasn’t anything that a bit of care couldn’t work around, fortunately.

Before finding this dodgy connector, [Steven] first tried to clean the front mechanical connectors, which took multiple sessions. This was followed up by oiling the mechanism. With the connector fixed and some cleaning, the meter’s display now read correctly. It still has some issues with starting up though, which [Steven] reckons are due to the old capacitors in the device.

Presumably some recapping will round off this fun device revival experience, but for the time being a Keithley Model 179 has been saved from e-waste, to inspire generations to come.

Multi-way Capacitor Replacement Without The Pain

February 1, 2024 by 20 Comments

Anyone who’s worked with older tube-based equipment will be familiar with the type of vintage electrolytic capacitor which integrated several capacitors into one can. Long obsolete, they can be bought as reproduction, but unfortunately at an eye-watering price. [D-Lab Electronics] introduces us to a solution using a very useful kit, that it’s worth sharing.

The piece of equipment in the video below the break is a rather lovely Heathkit oscillator, following the familiar phase shift model with a light bulb in its feedback loop. It’s a piece of test equipment that produces a low-distortion sine wave output, and would still be of use to an audio engineer today. He replaces the capacitor with two modern ones on a multi-cap board from [W8AOR], who sells a variety of these kits for different configurations.

We’ve done this very repair more than once, and it has usually involved wiring, heatshrink sleeving, hot glue, and cable ties, looking very messy indeed. It’s not that often that a kit catches our eye as this one has, but we know we’ll be finding it useful here some time in the future. Meanwhile if you’d like to know why this oscillator has a light bulb, take a look at our piece on distortion.

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Navigate Burning Man With Ease With This Custom Tool

February 1, 2024 by 7 Comments

When setting up a city in the desert, the team behind Burning Man does its best to lay things out in an ordered fashion. Even still, getting around at ground level can be a challenge at times, and it’s easy to get lost. To help get around easier, [Zach] developed a nifty GPS device built specifically for navigating the ephemeral clock-like city.

The device is built for a few simple purposes. It shows where you are, it helps you navigate somewhere you’ve been before, and it helps you navigate to portable toilets. It’s set up to be usable both on bike and on foot, the typical ways of getting around the playa. Since Black Rock City is fairly simple, it uses an arrow to point to a desired waypoint, and is capable of storing up to five points of interest. It’s built using a cheap GNSS receiver and transflective LCD screen, and a Pi Pico is the brains of the operation.

The value of the device is obvious, particularly when exploring deeper areas of the playa, or after the road signs have been removed or structures have been taken down or burnt to ashes. We’ve seen some other great projects from the desert festival before, too. If you’ve got your own playa-spec hacks, don’t hesitate to let us know!

Eliminate That Pesky Power-Only USB Cable With This Cable Tester

February 1, 2024 by 13 Comments

Ever wondered why your Arduino wasn’t programming, only to find out that the cable doesn’t have any data conductors? Worry not, [Spencer Maroukis] has got you covered with the USB Sleuth Cable Tester!

The cable tester is a beautiful black circular PCB, with USB ports of nearly every type on the edges. It works partially through passive detection with LEDs and otherwise through active detection of things like the orientation with an STM32 powered by a coin cell battery. But it gets better: There are disconnect switches and exposed pads to test some of the conductors with a digital multimeter!

It may not be necessary for all of us, but one thing is clear: When you needed a good USB cable, you wished you had this to actually test it. The design is open-source too, which is definitely nice if you want one for yourself.

Meanwhile this isn’t the first USB cable tester we’ve seen here.

Flat-Pack Multi-Tool Has Many Dimensions

February 1, 2024 by 4 Comments

Sometimes, you just have to see whether something can be done. Such is the case with [ToolTechGeek]’s flat-pack metal multi-tool build. Can an entire multi-tool be made with only flat pieces of laser-cut metal and fasteners? It would seem so, yes. And quite nicely, too, as you’ll see in the video after the break.

[ToolTechGeek] started by designing all the parts in Inkscape, and then made a few 3D printed versions to check fitment before committing to laser-cut metal. Once they had the pieces cut, everything came together nicely except for a few tabs that connect some of the parts together. These just had to be filed down a bit.

So now, [ToolTechGeek] has a handy set of pliers, flat- and Phillips-head screwdrivers, a knife, and a bottle opener all in one place. Although the pliers don’t have teeth, they still do a fine job of removing nuts and the like. Be sure to check out the final product and see it get put to the test.

No use for such a thing? Maybe you’d prefer an NFC multi-tool.

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How Much Longer Will Cars Have Cigarette Lighter Ports?

February 1, 2024 by 106 Comments

Depending on the age of your car, it might contain a round 12 V power outlet in the dash, or possibly in the elbow compartment. And depending on your own age, you might know that as the cigarette lighter port. Whereas this thing used to have a single purpose — lighting cigars and cigarettes via hot coil — there are myriad uses today, from charging a phone to powering a dash camera to running one of those tire-inflating machines in a roadside emergency.

But how did it come to be a power source inside the vehicle? And how long will it stick around? With smoking on the decline for several decades, fewer and fewer people have the need for a cigarette lighter than do, say, a way to charge their phone. How long will the power source survive in this configuration?

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This Time It’s Toyota: Takata Airbag Recalls Continue

February 1, 2024 by 23 Comments

The automotive industry is subject to frequent product recalls, as manufacturers correct defects in their vehicles that reveal themselves only after some use. While such events may be embarrassing for a marque, it’s not necessarily a bad thing — after all, we would rather put our trust in a carmaker prepared to own up and fix things rather than sweep their woes under the carpet.

There’s one recall that’s been going on for years which isn’t the vehicle manufacturer’s fault though, and now it seems Toyota are the latest to be hit, with some vehicles as old as two decades being part of it. Long time Hackaday readers will probably recognize where this is going as we’ve covered it before; at its centre are faulty airbag charges from Takata, and the result has been one of the largest safety related recalls in automotive history.

An automotive airbag is a fabric structure inflated at high speed by a small explosive charge when triggered by the sharp deceleration of an incident. It is intended to cushion any impact the occupant might make upon the car’s interior. The problem with the faulty Takata units is that moisture ingress could alter the properties of the charge, and this along with corrosion could increase its power and produce a hail of metal fragments on detonation.

Our colleague [Lewin Day] has penned a series of informative and insightful investigations of the technology behind the Takata scandal, going back quite a few years. With such relatively ancient vehicles now being recalled we can’t help wondering whether it would be easier for Toyota to run a buyback scheme and take the cars off the road rather than fix them in this case, but we’re curious as non automotive safety engineers why the automotive airbag has evolved in this manner. Why is one of very few consumer explosive devices not better regulated, why is it sold with an unlimited lifetime, and why are they not standardized for routine replacement on a regular schedule just like any other vehicle consumable?

2003-2004 Toyota Corolla: IFCAR, Public domain.