This is the name of an interesting lighting effects device for discos, ballrooms or even shop windows. This device with only 3 control circuits and lamps of only three basic colors, operating by the same principle as the color TV, allows to obtain 7 different colors in a panel. It is an optical cannon, which directly projects light onto a screen and whose color depends on the lamps that are lit at a certain moment. Using the SCR MCR106 load current of the order of 4 A, it is possible to control several different projectors, built in the same way and connected in parallel, so that they can be installed throughout the room to be lit. In each projector using 100 W lamps, you can control 4 units in the 110 V network and 8 units in the 220 V network. The colors are obtained by the positions of the excitation potentiometers R16, R17 and R18, while the adjustment cycles are achieved in potentiometers R4, R9 and R14. These cycles are also determined by the astable multivibrators, formed by the 6 transistors. The frequency of these can be changed by changing the value of capacitors from C1 to C6.
