Curiously Strong Power Supply Design

18VAC dual secondary 160VA toroid into a full wave rectifier with 32*470uF caps, for about 5.5Vpp ripple at 10A. Rectified output is fed into four MC34063 based SMPS supplies, three step-down and one inverting. The outputs of the SMPS are fed into 5 linear regulators, for a 15V bipolar rails, 15V power amp rail, 10V small amp rail, and 6V shifty VU rail. Designs are compatible with non through hole plate boards. All boards will be fabricated on a Taig 2019CR CNC mill.

cs_regulators_schema.png

Posted by rmrubin Posted in: Make2008, Electronics Comments Off April 2008

ATTiny44 Based Shifty VU Meter Controller (MAKE2008)

Schematic and circuit board design for the Shifty VU Controller. Designed for an Altoids tin chassis, the analog section includes a stereo full-wave rectifier made with a quad rail-to-rail opamp, with logic FET switched capacitors to adjust the rectifier output’s rolloff delay.

shifty_vu_controller_schema.png

Posted by rmrubin Posted in: Make2008, Electronics Comments Off April 2008

Curiously Strong TriAmp Speaker Selection

Tang Band drivers from Parts Express. 300Hz and 5KHz look good for crossover. $2 Goldwood tweeters. Not worth posting (even if they did have specs, which they don’t). Chassis is planned to be laser cut acrylic (!) courtesy of macetech and Techshop. A high density cardboard concrete/plaster casting tube may be integrated into the design as a waveguide for the 5″ driver. Open Baffle mid drivers are also being considered.

Posted by rmrubin Posted in: Make2008, Electronics Comments Off April 2008