The Luxaura LEDs are all connected in
parallel with the positive connection wired to the “C” terminal of the transistor.
There is data around that says a resistor
should be used in this connection with the transistor to limit current. This was calculated to be 180k but when I did tests the
LEDs did not light up very brightly. After some trial and error a 10k resistor worked best, the brightness was excellent and
nothing blew up or got hot even over extended tests. So that is really all there is to it.
Note: The Luxaura LED’s have
current limiting resistors built into
they can operate at 12 vdc. Normal LEDs can
this, they need correctly sized
current limiting resistors. Since
VU meter operates from 12 vdc it is simpler to have LEDs
use 12vdc. Current limiting resistors
must be calculated to take all
this into account.
When the first LED comes on it (remember
the first ones goes to the transistor) it turns on the Big Honkin transistor that switches on power for all 14 Luxura
LED’s. As an adjustment any LED could be removed and a wire connected up in its place.
For the small cost and effort required
this circuit works surprisingly well. The parts cost around $30, considerably less then the $80 or so for the Tech 22 Neon
music interface and transformer.
Here is a test with everything set up
on the table before installation in the torso: