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BNCs For An Old Instrument

Back in the summer our eye was caught by [Jazzy Jane]’s new signal generator, or perhaps we should say her new-to-her signal generator. It’s an Advance E1 from around 1950, and it was particularly interesting from here because it matches the model on the shelf above this bench. She’s back with a new video on the E1, allowing us a further look inside it as she replaces a dead capacitor, gets its audio oscillator working, and upgrades its sockets.

Treating us to a further peek inside the unit, first up is a leaky capacitor. Then a knotty question for old tech enthusiasts, to upgrade or not? The ancient co-ax connectors are out of place on a modern bench, so does originality matter enough to give it a set of BNC sockets? We’d tend to agree; just because we have some adapters for the unit here doesn’t mean it’s convenient. Following on from that is a period variable frequency audio mod which has failed, so out that comes and a little fault-finding is required to get the wiring of the audio transformer.

These instruments are not by any means compact, but they do have the advantage of being exceptionally well-built and above all cheap. We hope readers appreciate videos like the one below the break, and that you’re encouraged not to be scared of diving in to older items like this one to fix them. Meanwhile the first installment is here.

Apple iOS 18’s New Repair Assistant: Easier Parts Pairing Yet With Many Limitations

A stack of Activation Locked MacBooks destined for the shredder in refurbisher [John Bumstead]’s workshop.

Over the years, Apple has gone all-in on parts pairing. Virtually every component in an iPhone and iPad has a unique ID that’s kept in a big database over at Apple, which limits replacement parts to only those which have their pairing with the host system officially sanctified by Apple. With iOS 18 there seems to be somewhat of a change in how difficult getting a pairing approved, in the form of Apple’s new Repair Assistant. According to early responses by [iFixit] and in a video by [Hugh Jeffreys] the experience is ‘promising but flawed’.

As noted in the official Apple support page, the Repair Assistant is limited to the iPhone 15+, iPad Pro (M4) and iPad Air (M2), which still leaves many devices unable to make use of this feature. For the lucky few, however, this theoretically means that you can forego having to contact Apple directly to approve new parts. Instead the assistant will boot into its own environment, perform the pairing and calibration and allow you to go on your merry way with (theoretically) all functionality fully accessible.

The bad news here is that parts whose IDs show up as being locked (Activation Lock) are ineligible, which is something you cannot tell when you’re buying replacement parts. During [iFixit]’s testing involving swapping logic boards between two iPhone 15 Pros they found many issues, ranging from sudden reboots during calibration and boot looping. Some of these issues were due to the captive-portal-based WiFi network at [iFixit] HQ, but after eliminating that variable features like Face ID still refused to calibrate among other issues.

Meanwhile [Hugh]’s experiences have been more positive, but the limited nature of this feature, and the issues surrounding used and third-party parts, mean that the practical use of this Repair Assistant will remain limited, with tons of perfectly fine Activation Locked parts scrapped each year and third-party parts requiring pairing hacks to make basic features work, even on Apple’s MacBooks.

IOS 18 also adds battery monitoring for third-party batteries, which is a nice touch, but one cannot help but get the feeling that Apple is being dragged kicking and screaming into the age of easy repairs and replacements with Apple devices.


Featured image: A stack of Activation Locked MacBooks destined for the shredder in refurbisher [John Bumstead]’s workshop.

McDonalds Ice Cream Machines Gain A DMCA Exemption

Sad clown holding melted ice cream cone

An unlikely theatre for an act in the right-to-repair saga came last year in the form of McDonalds restaurants, whose McFlurry ice cream machines are prone to breakdown. The manufacturer had locked them down, and a franchisee with a broken machine had no option but to call them for an expensive repair job. iFixit and Public Knowledge challenged this with a request for a DMCA exemption from the Copyright Office, and now news emerges that this has been granted.

The exemption in question isn’t specific to McDonalds, instead it applies to retail food preparation equipment in general, which includes ice-cream machines. We’re guessing that franchisees won’t be breaking out the screwdrivers either, instead it’s likely to lower significantly the cost of a service contract for them and any other food industry operators hit with the same problem. Meanwhile any hackers who’ve picked up an old machine can now fix it themselves without breaking the law, and maybe the chances of your local Mickey D’s having no McFlurries have gone down.

This story has featured more than once on these pages, so catch up here, and here.

Simple PCB Repairs Keep Old Vehicle Out of the Crusher

For those of us devoted to keeping an older vehicle on the road, the struggle is real. We know that at some point, a part will go bad and we’ll learn that it’s no longer available from the dealer or in the aftermarket, at least at a reasonable cost. We might get lucky and find a replacement at the boneyard, but if not — well, it was nice knowing ya, faithful chariot.

It doesn’t have to be that way, though, at least if the wonky part is one of the many computer modules found in most cars made in the last few decades. Sometimes they can be repaired, as with this engine control module from a Ford F350 pickup. Admittedly, [jeffescortlx] got pretty lucky with this module, which with its trio of obviously defective electrolytics practically diagnosed itself. He also had the advantage of the module’s mid-90s technology, which still relied heavily on through-hole parts, making the repair easier.

Unfortunately, his luck stopped there, as the caps had released the schmoo and corroded quite a few traces on the PCB. Complicating the repair was the conformal coating on everything, a common problem on any electronics used in rough environments. It took a bit of probing and poking to locate all the open traces, which included a mystery trace far away from any of the leaky caps. Magnet wire was used to repair the damaged traces, the caps were replaced with new ones, and everything got a fresh coat of brush-on conformal coating.

Simple though they may be, we really enjoy these successful vehicle module repairs because they give us hope that when the day eventually comes, we’ll stand a chance of being able to perform some repair heroics. And it’s nice to know that something as simple as fixing a dead dashboard cluster can keep a car out of the crusher.

Heathkit Signal Generator Gets an Update

[DTSS_Smudge] correctly intuits that if you are interested in an old Heathkit signal generator, you probably already know how to solder. So, in a recent video, he focused on the components he decided to update for safety and other reasons. Meanwhile, we get treated to a nice teardown of this iconic piece of test gear.

If you didn’t grow up in the 1960s, it seems strange that the device has a polarized line cord with one end connected to the chassis. But that used to be quite common, just like kids didn’t wear helmets on bikes in those days.

A lot of TVs were “hot chassis” back then, too. We were always taught to touch the chassis with the back of your hand first. That way, if you get a shock, the associated muscle contraction will pull your hand away from the electricity. Touching it normally will make you grip the offending chassis hard, and you probably won’t be able to let go until someone kindly pulls the plug or a fuse blows.

These signal generators were very common back in the day. A lot of Heathkit gear was very serviceable and more affordable than the commercial alternatives. In 1970, these cost about $32 as a kit or $60 already built. While $32 doesn’t sound like much, it is equivalent to $260 today, so not an impulse buy.

Some of the parts are simply irreplaceable. The variable capacitor would be tough to source since it is a special type. The coils would also be tough to find replacements, although you might have luck rewinding them if it were necessary.

We are spoiled today with so many cheap quality instruments available. However, there was something satisfying about building your own gear and it certainly helped if you ever had to fix it.

There was so much Heathkit gear around that even though they’ve been gone for years, you still see quite a few units in use. Not all of their gear had tubes, but some of our favorite ones did.

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