The DGX-202, while not featuring dedicated 1/4" line outputs (S03 does!!!), it does have a 1/4" stereo headphone output which you could use. You'll want to get a 1/4" stereo-to-2x1/4" mono Y-cable, and preferably either 2 amps or some sort of line mixer that can properly sum the 2 mono channels into one mono channel. You could plug a regular 1/4" mono guitar cable directly into the DGX headphone socket, and plug it into the amp, but the sound quality may suffer a bit.