Classic Amp Revived With A Pi

July 5, 2022 by 4 Comments

Guitar amplifiers have a hard life, and as anyone who’s run a venue can tell you, they often have significant electrical issues after a life on the road. [Dsagman] had a Vox amplifier with fried internals, and rather than repair the original he rebuilt it with a Raspberry Pi inside to provide a fully-loaded array of effects.

Though the subject is the Vox, it’s best to see this as more a tale of how to create a guitar effect array in a Pi than specifically put it in an amplifier. The Pi has an audio board and an MCP3008 ADC added to it, and using those two it takes its inputs from a series of potentiometers and process the audio passing through the audio board. In addition there are a series of LED indicators and an LED bar graph to keep the user in touch with what’s going on.

The whole lot is nicely integrated in the VOX case with all the potentiometers on an aluminium panel. He discusses amplifier choice, but as you might expect the final choice is a Class D module. All in all an amp many readers would probably go for.

As long-time readers will remember, guitar effects have made quite a few appearances around here. Continue reading “Classic Amp Revived With A Pi” →

A clock with a VFD display in an orange TV-like case

Never Miss An Email With This 1970s Style Desktop Notifier

July 5, 2022 by 12 Comments

If you like the 1970s aesthetic but think bell-bottoms, big hair and psychedelic wallpaper are a bit too much in this day and age, you might want to have a look at [Pierre Muth]’s latest build, The Absurd Notifier. It’s a useful desk accessory that adds just a little bit of ’70s flair to your office: housed inside what looks like an orange TV standing on shiny metal feet is a little gadget that can tell you if you’ve got important email messages waiting or an appointment coming up.

[Pierre] built the system around a Garmin Vivosmart 3 smartwatch that he bought very cheaply because it had a broken display. The display’s pinout and protocol were of course undocumented, so [Pierre] hooked up his logic analyzer to try and figure out how it worked. It turned out to be a simple SPI setup, and with a bit of trial and error he was able to extract the images that the watch was sending out.

To replace the broken screen, [Pierre] turned to some 128×64 pixel VFD displays that he had left over from an earlier project. Their resolution was exactly the same as the Garmin’s original OLED display, but their interface wasn’t: the VFDs expected 115k2 serial data. Programming a PIC microcontroller with an SPI port on one side and a UART port on the other made for a simple bridge between the two.

[Pierre] then designed and 3D printed a case reminiscent of a 1970s TV, with matching bright orange color. The end result is a funky little retro clock that shows notifications on a vintage green display. If you like desktop notifiers, we seen several neat ones alerting their owners about things ranging from new YouTube subscribers to the ISS passing by.

Continue reading “Never Miss An Email With This 1970s Style Desktop Notifier” →

New Gear Saves Old Printer

July 5, 2022 by 18 Comments

As the digital photographic revolution took off, and everyone bought a shiny new film-less camera, there was a brief fad for photo printers. The idea was you’d have the same prints you’d always had from film, but the media for these printers would invariably cost a fortune so consumers moved on pretty quickly.

Now the pop up in second-hand stores and the like, which is how [Amen] acquired a Canon Selphy 740. It didn’t work, and on investigation it was found that a particularly tiny plastic gear had failed. Most people would have tossed the printer in the trash, but they instead opted to CNC-machine a new gear. It’s not everyday you tackle a job this small, so it makes for an interesting tale.

While the first instinct might be to reach reach for a CAD package, [Amen] instead wrote a script to create the raw GCode. The machining is done with a 0.2 mm bit ground to the desired profile. The result: a gear that gets the printer working again. It’s a dye-sublimation printer that leaves a negative image in the cartridge, allowing negative prints to be made with a bit of cartridge rewinding. And for those who might have ended up with a Selphy of their own, there’s a further post about using cheaper aftermarket cartridges.

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The Warm Glow Of A Luminous Clock

July 5, 2022 by 8 Comments

It seems there will never be an end to the number of ways to show the time. The latest is the LumiClock from [UK4dshouse], and it uses the seldom-seen approach of a sheet of luminous paper excited by a strip of UV LEDs that pass over it guided by a lead screw.

At its heart is a micro:bit, which generates the time in dot-matrix digital form as the LEDs are moved across the sheet. It in turn has a real-time-clock module to keep it on time, and it drives a little DC motor via a robotics driver board. The appearance of the whole devices is similar to an X-Y plotter without the Y axis, as a 3D-printed carrier is moved by the lead screw and slides along a pair of stainless steel tubes. The result is an unusual and eye-catching timepiece, whose retro dot-matrix numerals fade away and are refreshed with the new time.

We’ve had a bit of a play ourselves with UV luminous materials, and we can confirm they make an interesting alternative to some other display ideas in dimmer environments. This isn’t the first such clock we’ve shown you.

Hacker Camps Post-Pandemic, Electromagnetic Field 2022

July 5, 2022 by 21 Comments

After a four-year hiatus and a cancelled event, it was time earlier this month for British and European hackers to return to their field in Herefordshire. A special field, Eastnor Castle Deer Park, venue for the Electromagnetic Field 2022 hacker camp. I packed up an oversized rucksack and my folding bike, and set off to enjoy a few days in the company of my fellow geeks.

As the first of the large European hacker camps since 2019 there was both an excitement and a slight trepidation in finally hanging out with several thousand people, even if mostly outdoors. The UK has a good COVID vaccine uptake and the camp organisers requested that attendees test themselves before travelling to Eastnor, but after two years of precautions and the pandemic still being with us there’s still some risk to take into account. Happily they were able to strike a decent balance between precautions and event progress, and we were able to proceed with a fairly normal hacker camp.

Plenty Of Talks, But They’re Not Online Yet

Sadly the extensive programme of talks has yet to make it onto YouTube or media.ccc.de at the time of writing, so the section I’d normally devote to them may have to wait for another time. Thus this write-up is more about the social aspect than the action.

Eastnor Castle Deer Park lies in a secluded Herefordshire valley, and the entry is vla a small estate road that treats you to an unfolding vista as you approach, of the marquees and other structures nestled among the trees. The usual queue for a wristband and you’re in, with the minor inconvenience of a trek trough the site to wherever your village lies. This year I was with my hackerspace in the Milton Keynes Makerspace village, next to one of the estate roads at the side of the valley and clustered round a tent with the commendable purpose of distributing free cups of very high quality tea. My tent up, I was ready to tour the site, and renew some friendships after so long apart. Continue reading “Hacker Camps Post-Pandemic, Electromagnetic Field 2022” →

A wristwatch similar to the Berlin Uhr, with the actual Berlin Urh in the background

Tiny Berlin Clock Replica Also Counts Seconds

July 5, 2022 by 7 Comments

If you’re a clock aficionado and have ever visited Berlin, you’re probably familiar with the Berlin Clock on Budapester Straße: a minimalist design of yellow and orange lights that displays the time in a base-5 number system. This clock has been telling the time to the few that can read it since 1975, and is but one of several unusual clocks that can be found in the city.

Berlin resident [jjoeff] decided to make a miniature replica, appropriately called the Berlin Uhr Nano, in order to watch the unusual display at any time of day. Built around a Wemos D1 Mini, it connects to WiFi in order to synchronize its internal clock to an NTP time server. It then drives a custom PCB that holds 39 WS2812 LEDs to display the time in its proper format. Unlike the original though, it also includes a full counter to tell the number of seconds; the bigger clock just flashes a single lamp to show the seconds passing.

Powered by a 500 mAh lithium battery, it can be converted into a wristwatch by simply threading a strap through slots in the PCB. With no buttons for adjustment or any functionality other than displaying the time, it serves the same purpose as the original, just in a portable format. We’ve seen a slightly larger Berlin Clock replica made of wood before, as well as a round one that uses the same base-5 encoding scheme. Continue reading “Tiny Berlin Clock Replica Also Counts Seconds” →

Companies Rumored To Harvest Washing Machines For ICs

July 5, 2022 by 162 Comments

Wired and SCMP are reporting on interesting trivia from the realm of chip shortages. Apparently, some large conglomerate out there is buying new washing machines and scavenging the chips they can’t obtain otherwise. My imagination pictures skilled engineers in a production room, heavy-duty electric screwdrivers and desoldering toolkits on the floor next to them, and a half-torn-down washing machine about to reveal its control board with an STM32 right in the middle. This might not be the most skilled job, but it’s a change of pace, and hey, as long as the rate stays the same?

Whichever company is doing this, they’re in a conundrum for sure. One of the articles offers an example of a $350,000 spectrometer manufacturing being stalled by lack of a $0.50 part – while this feels exaggerated, it’s within the realm of possibility. For car manufacturers, the difference isn’t as dire, but still severe enough, and not meeting the production targets has ramifications other than the financial ones. It might indeed make sense to buy a $150 washing machine in order to finally be able to move a $30,000 car off the assembly line.
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