USB Hub Used For In System Programming

Did you order that 4-port USB hub because it was almost free but now it’s just sitting in your junk box? Why not turn it into an In System Programmer for AVR chips? [Paul] came up with HUB ISP as an answer to the chicken-or-egg problem we’ve seen with other diy programmers. It uses the data wires from four different USB cables to program AVR chips, enlisting the help of a 74HC00 NAND gate along the way. You do not need to have a programmed microcontroller as all the magic happens on the software end of things. The one caveat is that [Paul’s] method currently only works on Linux machines.

Color Clock Makes Telling Time Impossible

[Bogdan] set out to build the all-too-familiar binary clock. But, he didn’t want to be ordinary, and set the goal of making the clock as hard to read as possible. What he ended up with is a clock that is almost impossible to read correctly.
He’s using colors to tell the time. We immediately thought this might make use of resistor codes as the display but it doesn’t. Red shows the hours, green for minutes, and blue for seconds. Now stack all of them on top of each other in binary and you’ve got the time. That means you’ve got to know all of your color combinations, plus read the binary value correctly, to decipher the time. Add to that the display changing every second and we’re in trouble.
Aside from the user difficulty level, this is a really clean build. It uses an ATmega8535 in conjunction with our favorite DS3232 RTC chip. The etched board is nice and clean, making for an aesthetically pleasing clock.

Drawbot Produces Portraits… Very Slowly

This robot artist, the Drawbot, produces images using an Arduino and Processing. A piece of paper is attached to a wall as a stylus connected to a couple of stepper motors scribbles out patterns that gradually become the image seen above. Each drawing is different and can take several weeks of constant operation to finish. That must have made debugging a real problem for [Harvey] during development. We wonder if this would work with homemade pencils?

Adding Compact Flash To An Old Sequencer

[Shoji] has a beloved sequencer that went out of production ten years ago. Unfortunately the storage options are also 10 year out-of-date as SCSI is the stock option for storing his loops. Using a series of adapters he added Compact Flash storage to his Akai MPC-2000 Classic. The board has a connector for 25-pin SCSI which he wired to a 25-pin to 50-pin SCSI adapter. From there he connects a SCSI to IDE board, and then an IDE to CF. Subsequent versions of the Akai Classic have floppy drives in the front left corner so he used this method to mount he CF slot. Now he’s got plenty of storage with very little change to the appearance of the looper.

Motorcycle Current Gear Indicator

[Vassilis Papanikolaou] just finished building a gear indicator for a motorcycle. This quite a simple implementation compared to some of the other vehicle information displays we’ve taken a look at. You should be able to build and install your own without breaking the bank. An ATtiny25 microcontroller reads data from a couple of hall effect sensors and the neutral switch, then displays the current gear on a 7-segment display.

There’s a magnet on the shifter and two hall effect sensors at the position for ‘gear up’ and ‘gear down’ shifting. The AVR chip keeps track of these and even stores the last position in EEPROM when you shut the bike off. If the device somehow gets off track, it will automatically recalibrate itself next time you shift into neutral, thanks to the bike’s neutral sensor switch.

1000W Induction Heater

[Tim Williams] likes to heat things up with this induction heater he built. At peak it can use 1000W and as you can see in the video, that’s more than enough power to heat, burn, and melt a plethora of different objects. The case design uses a center divider to isolate switching noise from the magnetic field with the whole unit housed in aluminum because it won’t heat up from stray magnetic fields. He’s selling plans and kits in case you want one, but we just don’t know what we’d use it for.

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