IC1 TEA2000 (PAL/NTSC Colour Encoder supporting 64 colours)
RV1 variable resistor - turning this controls brightness
VC1 variable resistor - turning this controls colour (too far to the left or right and you get black/white, when colour appears, turning it can result incolour movement in one direction, then stable and then in the other direction).
L1 variable resistor - unknown operation. it doesn't seem to do anything.