There seem to be two schools of thought when it comes to picking an enclosure for your cyberdeck project: you either repurpose the carcass of some commercially produced gadget, or you build a new case yourself. The former can lead to some very impressive results, especially if your donor device is suitably vintage, but the latter is far more flexible as the design will be based on your specific parameters.
But for the CyberTapeDeck, [Matthew] decided to take a hybrid approach. The final product certainly looks like it’s built into a 1980s portable tape deck, but on closer inspection, you’ll note that the whole thing is actually 3D printed. The replica doesn’t just nail the aesthetics — it also includes the features you’d expect from the real thing, including an extendable handle and functional buttons which the internal Raspberry Pi 3 sees as a macropad thanks to an Arduino Pro Micro.
A seven inch LCD stands in for the tape door, and while it unfortunately doesn’t look like [Matthew] was able to replicate the opening mechanism to angle the display, you can at least stand the whole thing on its end to provide a more comfortable viewing experience.
[Matthew] says one of the intended purposes for this cyberdeck is to get his son excited about working with electronics and programming, so in a particularly nice touch, he’s mounted a terminal block over the “speaker” that ties into the Pi’s GPIO pins. This provides a convenient interface for experimenting on the go, without getting tangled up in exposed wiring.
Back in the early days of the home computer revolution, data was commonly saved on tape. Even better, those tapes would make an almighty racket if you played them on a stereo, because the data was stored in an audio format. The Simple Universal Modem from [Anders Nielsen] is built to work in a similar way, turning data into audio and vice versa.
The project consists of a circuit for modulating data into audio, and demodulating audio back into data. It’s “universal” because [Anders] has designed it to be as format-agnostic as possible. It doesn’t matter whether you want to store data on a digital voice recorder, a cassette deck, or an old reel-to-reel. This build should work fairly well on all of them!
On the modulation side of things, it’s designed to be as analog-friendly as possible. Rather than just spitting out rough square waves, it modulates them into nice smooth sine waves with fewer harmonics. On the demodulation side, it’s got an LM393 comparator which can read data on tape and spit out a clean square wave for easy decoding by digital circuitry.
If you find yourself trying to recover old data off tapes, or writing to them for a retrocomputing project, this build might be just what you need. [Anders] even goes as far as demonstrating its use with an old reel-to-reel deck in a helpful YouTube video.
There really were some weird ways of storing data way back when. Just ask IBM. Video after the break.
The build uses a Raspberry Pi Pico, which employs PWM to control the speed of the tape drive’s motor. This is achieved with the use of an NPN transistor driven by the PWM output of the Pico. This allows accurate control of motor speed, and thus pitch.
With that sorted out, the project was fleshed out with an OLED screen and a rotary encoder. These allow various patches or scripts to be run on the Pico, controlling the motor speed of the tape player in various ways. With a bit of work, [Issac] was also able to create a function that converted MIDI note values into PWM values that determine various motor speeds.
The natural thing to do next was to put in a tape with a looping sample at a set pitch, and then vary it in a sequence controlled by the Pico. The 8 steps of the sequence can be manually set with the rotary control, and in future, [Issac] even plans to add a real MIDI input, allowing the system to act as a monophonic synth.
In our no-nonsense journey through the world of audio technology we’ve so far have looked at digital audio and the vinyl disk recording. What’s missing? Magnetic tape, the once-ubiquitous recording medium that first revolutionised the broadcast and recording industries in the mid-20th-century, and went on to be a mainstay of home audio before spawning the entire field of personal audio. Unless you’re an enthusiast or collector, it’s likely you won’t have a tape deck in your audio setup here in 2021 and you’ll probably be loading your 8-bit games from SD card rather than cassette, but surprisingly there are still plenty of audio cassettes released as novelties or ephemeral collectables.
The Device That Made The Sound Of The Latter Half Of The 20th Century
The first magnetic recordings were made directly on metal wires, but metal fatigues as it bends. By coating a flexible plastic tape in ferrous particles, the same simple technique of laying down an audio signal as variations in the magnetic field could be made smaller, lighter, and more robust. But the key to the format’s runaway success is the technical advancements that differentiate those 1950s machines from their wire recorder ancestors.
Whether it is a humble cassette recorder or a top-end studio multitrack, all tape recorders are very similar. There are two reels that hold the tape: the playback reel that houses the recording, and the take-up reel that stores the tape as it plays in the machine. The take-up reel is lightly driven to run faster than the tape speed, and the playback reel has a slight braking force to keep the tape under tension at all times. Continue reading “Know Audio: Mixtapes, Tape Loops, And Razor Blades”→
Way back in the previous century, people used to use magnetized strips of tape to play music. It might be hard to believe in today’s digital world, but these “cassette” tapes were once all the rage. [Steve] aka [pinter75] recently found a Bang & Olufsen stereo with this exact type of antequated audio playback device, and decided to upgrade it with something a little more modern.
Once the unit arrived from eBay and got an electronic tune-up, [pinter75] grabbed a Galaxy S3 out of his parts drawer and got to work installing it in the old cassette deck location. He used a laser cutter to make a faceplate for the phone so it could be easily installed (and removed if he decides to put the tape deck back in the future).
The next step was wiring up power and soldering the audio output directly to the AUX pins on the stereo. Once everything was buttoned up [pinter75] found that everything worked perfectly, and mounted the stereo prominently on his wall. It’s always great when equipment like this is upgraded and repaired rather than thrown out.
The retro boombox was delivered with a few scratches and a broken radio, but the tape decks were still in decent shape so it was ready to be hacked. [speedfox] tied the Bluetooth audio output to the tape reader on one of the boombox’s tape decks, but this revealed a problem: the bass was overwhelming the rest of the sound. [speedfox] fixed this by adding a filter which worked until the power was tied in to the Bluetooth module and produced a lot of RF noise in the audio output. THIS problem was finally resolved with an audio transformer on both sides of the stereo signal. Finally!
After putting all of the new electronics in the case (and safely out of the way of the 120V AC input!) [speedfox] now has a classy stereo that’s ready to rock some Run-D.M.C. or Heavy D. He notes that the audio filter could use a little tweaking, and he’d also like to restore the functionality of the original buttons on the boombox, but it’s a great start with more functionality than he’d get from something off-the-shelf!
[Mattias] brings the awesome once more with his LEGO robot that sets up dominoes. You’ll remember his work from the wooden keyboard case and the mechanical binary adder. This time around he’s still exercising those woodworking skills by making his own domino tiles, but it’s the robot that makes this interesting. In the must-see video after the break the device lays perfectly straight, perfectly spaced dominoes just begging to be upset by a spoiled toddler. The robot is nothing more than handful of LEGO parts powered by a tape deck motor. The parts may be meager, but there’s an abundance of ingenuity tied up in the design.