[Adrian] has a lot of retrocomputers, so he uses an RGB to HDMI converter to drive modern monitors. In particular, he has a box that uses a programmable logic chip to read various RGB signals and ships them to a Raspberry Pi Zero to drive the HDMI output. Sounds great until, of course, something goes wrong.
A converter that had worked stopped working due to a bad board with the programmable logic chip on it. Unlike the retrocomputers, this board has little tiny surface mount components. A little analysis suggested that some of the chip pins were not accepting inputs.
[Johnny] had a monitor that he was particularly fond of. The whole monitor appeared dead, and he decided to open it up and find out what could be wrong. He wound up fixing it — sort of — using a hairdryer. While we think his explanation of the problem is unlikely, we hate to armchair quarterback, and we applaud that he opened it up and got it working.
When something is dead, it is always a good idea to check the power and power supply, but that didn’t pan out in this case. In fact, the power supply board inside had what looked like reasonable voltage values throughout. The problem had to be something more subtle.
We’ve all marveled at the videos of SpaceX rockets returning to their point of origin and landing on their spindly deployable legs, looking for all the world like something pulled from a 1950s science fiction film. On countless occasions founder Elon Musk and president Gwynne Shotwell have extolled the virtues of reusable rockets, such as lower operating cost and the higher reliability that comes with each booster having a flight heritage. At this point, even NASA feels confident enough to fly their missions and astronauts on reused SpaceX hardware.
Even so, SpaceX’s reusability program has remained an outlier, as all other launch providers have stayed the course and continue to offer only expendable booster rockets. Competitors such as United Launch Alliance and Blue Origin have teased varying degrees of reusability for their future vehicles, but to date have nothing to show for it beyond some flashy computer-generated imagery. All the while SpaceX continues to streamline their process, reducing turnaround time and refurbishment costs with each successful reuse of a Falcon 9 booster.
When a treasure of retrotechnology fails to work, the natural next step is to have a go at repairing it. [Adam Wilson] found himself in this position when he acquired a 1974 Sinclair Cambridge Scientific calculator, and his progress with the device makes for an interesting read.
First up is something of value to all old Sinclair enthusiasts, he’s found a solution to the original battery connectors being prone to failure. A couple of parts stocked by RS can be used as replacements, which should save quite a lot of Sinclairs with crusty connectors.
Saving the connectors should have fixed the calculator, but only served to reveal that it had an electronic fault. Some detective work traced this to the power supply, which is a small switching circuit. The 1974 chip and associated coil had both failed, which rather drew the project to a halt. A second repair-or-spares Cambridge Scientific was sourced, and by good luck it happened to have a working PCB. So [Adam] got a working calculator, and we hope he’ll succumb to the temptation to shoehorn in a PSU from 2022 to get the other one working.
Join Hackaday Editor-in-Chief Elliot Williams and Managing Editor Tom Nardi for a review of all the tech that’s fit to print. Things kick off with an update about the Hackaday Prize and a brief account of the 2022 Vintage Computer Festival East. Then we’ll talk about an exceptionally dangerous art project that’s been making the rounds on social media, a smart tea kettle that gave its life so that others can hack their device’s firmware, some suspiciously effective plant grow lights, and the slippery slope of remote manufacturer kill switches. We’ll wrap things up with some thought provoking discussion about personal liability as it pertains to community repair groups, and a close look at what makes synthetic oil worth spending extra on.
Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments below!
When you’ve gone to the trouble of building your own backyard railway, chances are pretty good that at some point, you’re going to want to add a locomotive of some sort. After all, nobody wants to be stuck using muscle power to move carts around. But what exactly are you going to power your locomotive with? And will it be up to the tasks you envision it handling?
Answering such questions calls for rigorous calculations using established engineering principles — or, if you’re [Tim] from the Way Out West channel on YouTube, just throwing a pneumatic engine on wheels and seeing what happens. The railway that [Tim] built is for his farm in County Cork, where he plans to use it to haul wood that he’ll make charcoal from. We’ve seen a little about his rails and rolling stock before, which has been a low-budget and delightfully homebrewed undertaking. So too with his pneumatic engine, seen in the video below, which uses cam-operated valves to control a pair of repurposed hydraulic cylinders to turn a big flywheel.
Using scuba tanks, [Tim] was able to power the engine for a full fourteen minutes — very encouraging. But would the engine have the oomph needed for real farm work? To answer that, [Tim] plunked the engine on a spare bogie, connected the engine shaft to one of the axles with a length of rope, and let it go. Even with no optimization and zero mechanical advantage, the engine was easily able to move a heavy load of sleepers. The makeshift pneumatic railway even managed to carry its first passenger, [Tim]’s very trusting wife [Sandra].
There’s clearly more work to do here, and many problems to overcome. But we really appreciate the “just try it” approach [Tim] employed here, and with a lot of what he does.
A huge part of the work our community does, aside from making things and doing a lot of talking about the things we’d like to make, involves repair. We have the skills to fix our own stuff when it breaks, we can fix broken stuff that other people throw out when it breaks, and we can fix broken stuff belonging to other people. As our consumer society has evolved around products designed to frustrate repairs and facilitate instead the sale of new replacements for broken items this is an essential skill to keep alive; both to escape having to incessantly replace our possessions at the whim of corporate overlords, and to fight the never-ending tide of waste.
So we repair things that are broken, for example on my bench in front of me is a formerly-broken camera I’ve given a new life, on the wall in one of my hackerspaces is a large screen TV saved from a dumpster where it lay with a broken PSU, and in another hackerspace a capsule coffee machine serves drinks through a plastic manifold held together with cable ties.
We do it for ourselves, we do it within our communities, and increasingly, we do it for the wider community at large. The Repair Café movement is one of local groups who host sessions at which they repair broken items brought in by members of the public, for free. Their work encompasses almost anything you’d find in a home, from textiles and furniture to electronics, and they are an extremely good cause that should be encouraged at all costs.
For all my admiration for the Repair Café movement though, I have chosen not to involve myself in my local one. Not because they aren’t a fine bunch of people or because they don’t do an exceptionally good job, but for a different reason. And it symbolically comes back to an afternoon over thirty years ago, when sitting in a university lab in Hull, I was taught how to wire a British mains plug. Continue reading “Ask Hackaday: Repair Café Or Not?”→
