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Re: [yamahacs80] Rogoffs' voice trigger LED board schematic?

2014-11-05 by David Rogoff

Hi.

The schematic is in the same photo group on the site:

It’s basically the same circuit that’s on the output of the KAS board.  If GATE is -6.5v (or around that - which is a “1”), the transistor is off so the 12k resistor pulls one side the LED to a positive voltage. The other side of the LED is ground, so this lights one of the two colored LEDs in the package.  If GATE is +8.5v (which is “0”), the transistor is on, pulling the LED to a negative voltage which lights the other color LED.  Or maybe I got it backwards.  Anyway, if it’s the other way, just flip the wires from the LED around :)

 David



On Nov 5, 2014, at 12:41 PM, r_j_d_2.phila@... [yamahacs80] <yamahacs80@yahoogroups.com> wrote:

hi all, so i was looking over the data on the rogoffs.com, and found images for the KAS wiring for the trigger LED, which i'm thinking of tackling. however, does anyone have the schematics/layout of the breadboard? thanks much, RJ

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