Restoring A 1924 Frigidaire B-9 Refrigerator Back To Working Condition

January 26, 2026 by Maya Posch 14 Comments

Before the refrigerator became a normal part of any kitchen, those with enough money to throw around could get an icebox, which used melting ice to cool food and drinks in a second compartment. As refrigerators became available for sale in the 1920s, this created somewhat awkward transition models, like the 1924 Frigidaire B-9 that [David Allen] recently got offered for a restoration. This was part of the restoration of a 1926 house, which foresaw putting this venerable unit back into operation.

As [David] explains, this refrigerator was still in use until about 1970 when it broke down, and repairs proved tricky. Clearly, the fault wasn’t that severe as [David] got it working again after a number of small repairs and a lot of maintenance. The running unit with its basic elements can be seen purring away in the completion video, with the journey to get there covered in a video series starting with the first episode.

What’s fascinating is that during this aforementioned transition period, the vapor compression electric cooling system was an optional extra, meaning that the basic layout is still that of an icebox. Correspondingly, instead of ice in the ice compartment, you find the low-side float evaporator, with the basement section containing the condensing unit, motor, and compressor. The temperature sensor is also a miracle of simplicity, using bellows that respond to the temperature and thus volume of the evaporator coolant, which trigger a switch that turns on the compressor.

Despite a hundred years having passed since this refrigerator was constructed, at its core it works exactly the same as the unit we have in our kitchens today, albeit with higher efficiency, more electronics, and with the sulfur dioxide refrigerant replaced with something less toxic to us humans.

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Repair And Reverse-Engineering Of Nespresso Vertuo Next Coffee Machines

January 21, 2026 by Maya Posch 35 Comments

Well there’s your problem. (Credit: Mark Funeaux, YouTube)

Akin to the razor-and-blades model, capsule-based coffee machines are an endless grind of overpriced pods and cheaply made machines that you’re supposed to throw out and buy a new one of, just so that you don’t waste all the proprietary pods you still have at home. What this also means is a seemingly endless supply of free broken capsule coffee makers that might be repairable. This is roughly how [Mark Furneaux] got into the habit of obtaining various Nespresso VertuoLine machines for attempted repairs.

The VirtuoLine machines feature the capsule with a bar code printed on the bottom of the lip, requiring the capsule to be spun around so that it can be read by the optical reader. Upon successful reading, the code is passed to the MCU after which the brewing process is either commenced or cruelly halted if the code fails. Two of the Vertuo Next machines that [Mark] got had such capsule reading errors, leading to a full teardown of the first after the scanner board turned out to work fine.

Long story short and many hours of scrubbed footage later, one machine was apparently missing the lens assembly on top of the photo diode and IR LED, while the other simply had these lenses gunked up with spilled coffee. Of course, getting to this lens assembly still required a full machine teardown, making cleaning it an arduous task.

Unfortunately the machine that had the missing lens assembly turned out to have another fault which even after hours of debugging remained elusive, but at least there was one working coffee machine afterwards to make a cup of joe to make [Mark] feel slightly better about his life choices. As for why the lens assembly was missing, it’s quite possible that someone else tried to repair the original fault, didn’t find it, and reassembled the machine without the lens before passing the problem on to the next victim.

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The Shelly 2.5 Smart Relay Design Flaw Killing Capacitors

January 17, 2026 by Maya Posch 33 Comments

Part of any self-respecting Smart Home, smart relays are useful for switching and monitoring loads that do not plug into an outlet. This also makes them a lot more integrated, and thus, a long lifespan is very welcome. Unfortunately, the popular Shelly 2.5 smart relays seem to be having a bit of a design flaw as they’re dying in droves once their 2-year warranty period is up. The cause and repair are covered in a recent [VoltLog] video on YouTube.

As noted in the Shelly documentation for the device, it’s a very compact form factor device, with screw terminals, two relays, and three fairly large electrolytic capacitors sharing very little space with the rest of the components. The apparent flaw comes in the form of these capacitors failing, with the video showing that one 100 µF capacitor has a massively increased ESR, likely due to electrolyte venting. This results in the observed symptoms, such as WiFi connectivity issues and audible hissing, the latter of which is demonstrated in the video.

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A New Life For An Old Amplifier

January 14, 2026 by Jenny List 23 Comments

An audio amplifier was once a fairly simple analogue device, but in recent decades a typical home entertainment amplifier will have expanded to include many digital functions. When these break they are often proprietary and not easy to repair, as was the case with a broken Pioneer surround-sound device given to [Boz]. It sat on the shelf for a few years until he had the idea of a jukebox for his ripped CDs, and his returning it to life with a new main board is something to behold.

Internally it’s a surprisingly modular design, meaning that the front panel with its VFD display and driver were intact and working, as were the class AB amplifier and its power supply. He had the service manual so reverse engineering was straightforward, thus out came the main board in favor of a replacement. He took the original connectors and a few other components, then designed a PCB to take them and a Raspberry Pi Pico and DAC. With appropriate MMBASIC firmware it looks as though it was originally made this way, a sense heightened by a look at the motherboard inside (ignoring a couple of bodges).

We like seeing projects like this one which revive broken devices, and this one is particularly special quality wise. We’re more used to seeing it with gaming hardware though.

Fixing A KS Jive DAB Radio With A Dash Of Fake ICs

January 13, 2026 by Maya Posch 14 Comments

The radio unit after a successful repair. (Credit: Buy it Fix it, YouTube)

The exciting part about repairing consumer electronics is that you are never quite sure what you are going to find. In a recent video by [Mick] of Buy it Fix it on YouTube the subject is a KS Jive radio that throws a few curve balls along the way. After initially seeing the unit not power on with either batteries or external power, opening it up revealed a few loose wires that gave the false hope that it would be an easy fix.

As is typical, the cause of the unit failing appears to have been a power surge that burned out a trace and obliterated the 3.3V LDO and ST TDA7266P amplifier. While the trace was easily fixed, and AMS1117 LDOs are cheap and plentiful, the amplifier chip turned out to be the real challenge on account of being an EOL chip.

The typical response here is to waddle over to purveyors of scrap hardware, like AliExpress sellers. Here [Mick] bought a ‘new’ TDA7266P, but upon receiving his order, he got suspicious after comparing it with the busted original. As can be seen in the top image, the markings, logo and even typeface are wildly different. Thus [Mick] did what any reasonable person does and x-rayed both chips to compare their internals.

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Repairing Brittle Plastic Retro Computer Cases

January 8, 2026 by Maya Posch 20 Comments

Using UV resin as glue for new case clips. (Credit: More Fun Making It, YouTube)

As computers like the venerable breadbox Commodore 64 age, their plastic doesn’t just turn increasing shades of yellow and brown, the ABS plastic also tends to get brittle. This is a problem that seems to plague many plastic cases and enclosures, but fortunately there are some ways to halt or even reverse the heavy toll of time, with the [More Fun Making It] YouTube channel exploring a number of methods, including UV-curable resin, PETG 3D-printed clips and silicone molds.

Aside from large-scale damage, screw posts tend to snap off a lot, either during shipping or when merely trying to open the case. The same is true for the clips around the edge of the C64 case, which rarely survive that long. Gluing a case clip back on with epoxy or such somewhat works, but is messy and not that durable.

Instead UV resin is used, together with newly printed clips in translucent PETG. The remnants of the old clips are removed, followed by the application of the resin. The clips are actually a modified version of a VIC-20 case clip design by [Ken Mills]. With the UV resin as glue, curing is almost instant with a UV lamp unlike the tedious process with epoxy.

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DIY Grid Dip Meter Teardown

January 7, 2026 by Al Williams 5 Comments

You don’t see them much anymore, but there was a time when any hobbyist who dealt with RF probably had a grid dip meter. The idea was to have an oscillator and measure the grid current as it coupled to external circuits. At resonance, the grid current would go down or dip, hence the name. In the hands of someone who knew how to use it, the meter could measure inductance, capacitance, tuned circuits, antennas, and more. [Thomas] takes a peek inside a homebrew unit from the 1950s in a recent video you can see below.

These meters often have a few things in common. They usually have a plug-in coil near the top and a big tuning capacitor. Of course, there’s also a meter. You have to pick the right coil for the frequency of interest, which both sets the oscillator frequency range and couples to the circuit under test.

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