Austin is whirling with South by Southwest excitement, so why not make some swirly radio noises?

Yes, Handmade Music Austin does have a big blowout party in the midst of South by, with a huge music lineup. Wish I could be there, gang, but I’ll be staying here in NYC.

On the docket:

FREE performances starting at noon by Florene, The Hearts & the Minds, WHITE, The Loud Objects, Bodytronix

$10 for a workshop

Registration and details:
Handmade Music Austin #6 Super Show + update

Eric Archer writes:

I’m rolling out a new kit for HMA#6. Its called Tune In Tokyo and makes swirly noises like tuning an old fashioned short wave radio. Its just a cartoonish version of the real thing, but when I hear it I think OLD RADIO!! As some of the boys have pointed out, there was an .. um .. playground game by the same name, which is explained fully in urbandictionary for the curious. That’s Mt. Fuji on the board art.

The circuit has three square wave oscillators made from a 4584 (same as 40106), and an LFO. The LFO sweeps the frequency of a fourth oscillator made with 74HC4046. These frequencies drive the inputs of a 74HC594 shift register. Its outputs are sent thru a network of specially weighted resistors, which are designed to convert 1’s and 0’s into a sine wave. This digital sinewave generator recipe is an interesting shortcut to sine wave generation and I’ve only seen it in Don Lancaster’s CMOS cookbook (1977). The opamp at the end of the resistor net is just there as a buffer. This circuit gets its sound by abusing the properties of the digital sine wave generator via decimation and aliasing effects.

This is only one of the kits we’ll teach at HMA6; we decided to create a free-for-all where folks can select from a menu of kits and seat themselves at a table where others are building the same kit. We’ll also be offering the Autonomous Bassline, Nebulophone, and some of our beginner kits as well. Should be crazy enough to fit with the SXSW insanity that pervades Austin this time of year!

If you make it and record some of the action, do share!

This board makes swirly whirly noises.