MIDI And Vintage FM Synthesis


Before the days when computers could play and record audio that far surpassed the quality of CDs, sound cards were very, very cool. Most audio chips from the 80s, from the Commodore SID is pretty much a synth on a chip, but you can also find similar setups in ancient ISA sound cards. [Emilio] pulled one of these cards with an ADLIB OPL2 chip on it, and used a PIC micro to create his very own FM synthesis synth (IT, translatatron, although Google is screwing up the formatting).

The Yamaha YM3812 chip, otherwise known as the OPL2, was a fairly complete synthesizer in a very tiny package using FM synthesis for some very unique sounds. Once [Emilio] had the PIC sending commands to the sound chip, he added MIDI support, allowing him to play this vintage ‘synth on a chip’ with a keyboard instead of a tracker.

Judging from the video below, it sounds great, and that’s with [Emilio] mashing the keys for a simple demo.

[Read more...]

Ask Hackaday: Global Energy Transmission – Can It Work?

global transmission logo with earth in the background

Atop a small mountain in Colorado Springs sat the small, makeshift laboratory of Nikola Tesla. He chose this location because the air was thinner, and therefor more conductive. Tesla had come to believe that he could use the Earth as a conductor, and use it to send electrical power without the need for wires. Though some facts are forever lost, it is said that on a clear, moonless night, Tesla flipped the switch that fed millions of volts into a large coil that towered high into the air. He cackled maniacally as an eerie blue corona formed around the crackling instruments, while some 200 florescent bulbs began to glow over 25 miles away.

A magnificent feat took place in the hills of Colorado that night. A feat that surely would change the world in how it harnessed electricity. A feat that if brought to its full potential, could provide wireless power to every point on the globe. A feat that took place almost one hundred and twenty years ago…


[Read more...]

The Raspi GameBoy For The Rest Of Us

We’ve seen quite a few casemods that stuff a Raspberry Pi into a Game Boy with all the required to turn it into a very cool portable Pi and retro gaming device. Most of these builds use a modified 20-year-old Game Boy for the enclosure, and if you have an attachment to your old green screened friend, you might not want to cut it up for a Pi project. [Noe] over at Adafruit has a solution – a 3D printed Game Boy enclosure that turns a Pi and TFT screen into a barely pocketable Raspberry Pi, with all the buttons and batteries required for taking an installation of RetroPi on the road.

The PiGRRL, as this build is called, uses the Adafruit touchscreen TFT kit for the Pi, effectively turning the Pi into a very tiny tablet. This allows for normal desktop interaction with the Pi, and it’s also small enough to fit in the smallest of enclosures.

The 3D printed enclosure is the star of the show here, allowing complete access to most of the Pi’s ports, while allowing enough space in the rest of the enclosure for a largish battery, charging circuit, and buttons taken from an SNES controller.

The end result is a very usable portable Pi that just happens to be in the perfect form factor for loading up a few ROMs and playing some classic video games. Video below.

[Read more...]

C64 Emulator For The Arduino Due


Almost a year ago, [miker00lz] started a thread on the Arduino forums telling everyone about a 6502 emulator and BASIC interpreter he wrote for an Arduino Uno. The chip inside the Uno isn’t a powerhouse by any means, and with only 2KB of RAM it’s far less capable than just about any computer from the 70s. Arduino works on a lot of different chips, though, and after a few months, [Jan] turned an Arduino Due into a Commodore 64 emulator.

[Jan]‘s code isn’t limited to the DUE, and can be used with any chip with enough memory. If you’re feeling fancy, you can connect a TFT display for all the vintage goodness of PETSCII graphics, all while running a faster BASIC than the very stripped down EHBASIC.

Because the emulator is using software to talk to the outside world, it should be possible to use this project to interface with the cooler chips found in Commodore machines – SIDs for one, but also the cartridge port for some vintage Ethernet goodness. It’s not even limited to Commodore machines, either: the POKEY chips found in Atari 8-bit micros are seriously underutilized in the chiptune and demoscene, and having modern hardware to play with these chips couldn’t hurt in the slightest.

[Read more...]

XOXO for the OCXO


[Kerry Wong] recently got himself a frequency counter. Not just any counter, a classic Hewlett-Packard 5350B Microwave Counter. This baby will go 10Hz all the way up to 20GHz with only one input shift. A true fan of Hackaday Prize judge [Dave Jones], [Kerry] didn’t turn it on, he took it apart. In the process, he gave us some great pictures of late 80’s vintage HP iron.

Everything seemed to be in relatively good working order, with the exception of the oven indicator, which never turned off. The 5350B had three time bases available: a Thermally Compensated Crystal Oscillator (TCXO),  an Oven Controlled Crystal Oscillator (OCXO), and a high stability OCXO. [Kerry's] 5350B had option 001, the OCXO. Considering it was only a $750 USD upgrade to the 5350B’s $5500 USD base price, it’s not surprising that many 5350B’s in the wild have this option.

[Kerry] checked the wattage of his 5350B, and determined that it pulled about 27 watts at power up and stayed there. If the OCXO was working, wattage would have dropped after about 10 minutes when the oven came up to temperature. Time to tear open an oven!

Armed with a copy of the 5350B service manual from HP’s website, [Kerry] opened up his OCXO. The Darlington transistors used as heaters were fine. The control circuit was fine. The problem turned out to be a simple thermal fuse. The service manual recommended jumping out the fuse for testing. With the fuse jumped, the oven came to life. One more piece of classic (and still very useful) test equipment brought back to full operation.

[via Dangerous Prototypes]

The Old Ping-Pong Ball Levitation Trick


[Jacob] has put a slightly new twist on the levitating ball trick with his ping-pong ball levitation machine. We’ve all seen magnetic levitation systems before. Here on Hackaday, [Caleb] built a Portal gun which levitated a Companion Cube. Rather than go the magnetic route, [Jacob] levitated a ping-pong ball on a cushion of air.

Now, it would be possible to cheat here, anyone who’s seen a demonstration of Bernoulli’s principle knows that the ball will remain stable in a stream of air. [Jacob] proves that his system is actually working by levitating ping-pong balls with different weights.

A Parallax Ping style ultrasonic sensor measures the distance between the top of the rig and the levitating ball. If the ball gets above a set distance, [Jacob's] chipKit based processor throttles down his fans. If the ball gets too low, the fans are throttled up. A software based Proportional Integral Derivative (PID) loop keeps the system under control. A graph of the ball distance vs fan speed is displayed on an Android tablet connected to the controller via USB.

When [Jacob] switches a heavy ball for a light one, the lighter ball is pushed beyond the pre-programmed height. The controller responds by reducing the fan speed and the ball falls back. Who said you can’t do anything good with a box of corn dogs?

[Read more...]

Pocket Calculator Emulates Pocket Calculator

msp430 Calc Emu

[Chris] has built a pocket calculator that emulates… a pocket calculator. Two pocket calculators, in fact. Inspired by [Ken Shirriff's] incredible reverse engineering of the Sinclair scientific calculator, [Chris] decided to bring [Ken's] Sinclair and TI Datamath 2500II simulators to the physical world.

Both of these classic 70’s calculators are based on the TMS0805 processor. The 0805 ran with 320 11-bit words of ROM and only three storage registers. Sinclair’s [Nigel Searle] performed the real hack by implementing scientific calculator operations on a chip designed to be a four function calculator.

[Chris] decided to keep everything in the family by using a Texas Instruments msp430 microcontroller for emulation. He adapted [Ken's] simulator code to run on a MSP430G2452. 256 bytes of RAM and a whopping 8KB of flash made things almost too easy.[Chris'] includes ROMs for both the TI and the Sinclair calculators. The TI Datamath ROM is default, but by holding the 7 key down during boot, the Sinclair ROM is loaded. The silk screen includes key icons for both calculators, as well as some Doge-inspired wisdom on the back.

All joking aside, these really are amazing little calculators. Children of the 60’s and 70’s will be taken back when they see the LEDs flash as the emulated TMS0805 performs algorithmic arithmetic. [Chris'] code is up on Github. While he hasn’t released gerbers yet, he does have images of his PCB layout on the 43oh.com forums.

[Read more...]