Main Features
Full
digital design using a DSP microcontroller (dsPIC)
Powered
from 230-240VAC or 115-120VAC mains with auto-detection of mains
frequency
Four
phase-controlled output channels (8-bit resolution)
Optocoupled Triac triggering for complete isolation of control circuitry
from output circuitry
Zero
voltage switching of Triacs for minimum RF interference
Four
mains outputs rated at 800W each (240VAC) or 400W (120VAC)
Selectable gain plus selectable minimum and maximum frequencies for each
output channel
Selectable filament preheat current for each output
channel
Persistent software settings
Self-diagnostics
Chaser
modes
Direct
stereo inputs for audio modulation of lights
Microphone input/third channel input for audio modulation of
lights
7x15
pixel dot-matrix LED display for menus
Dot-matrix display can function as a spectrum analyser, screen saver or
VU meter
Software-controlled input selection with software mixing
Adaptive
potentiometer control for software settings
Optional provision
for ICSP (in-circuit serial programming)
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In presenting this brand new project, we are reviving a name
which became synonymous with party light shows in the 1970s and 1980s. Long time
readers will be familiar with the "Musicolour" light shows which were presented
in "Electronics Australia", the last one being the Musicolour IV in the August
1981 issue.
SILICON CHIP magazine followed the same
theme with the Discolight project in the July & August 1988 issues and
produced a 12V version called the "Lightshow" in the January & February 1998
issues.
This photo and the photo on the facing page show the completed DSP Musicolour boards fitted to the case. The displays have been lit by temporarily powering the Display Board using an external DC supply.
All of these projects were analog designs based on op amps and
logic ICs. The audio was passed through different pass-band filters for each
channel and the filtered outputs were used to drive either phase-controlled
Triacs in the Musicolour and Discolight circuits or power Mosfets in switchmode
in the case of the 12V Lightshow.
The logic ICs were used in the Discolight and 12V Lightshow to
produce the chaser modes, which were alternating patterns controlling the output
channels in the absence of an audio input. These chaser modes meant that you
could have pleasing lighting effects without any music.
Two decades on from the Discolight we now present the brand new
DSP Musicolour, a full digital design using DSP (digital signal processing). It
is based on a single DSP microcontroller to produce a comprehensive list of
features that were simply not possible with previous analog designs.
The DSP Musicolour operates from 230-240VAC or 115-120VAC mains
(detecting the 50Hz or 60Hz mains frequency automatically) and drives four
channels of incandescent lights. The total power output rating is 2400W for the
230-240VAC 10A version and 1600W for the 115-120VAC 15A version. For the 240VAC
version, each channel is rated at 800W maximum (as long as total power is less
than 2400W). For the 120V version, each channel is rated at 400W.
