In this video the man describes of the circuit bending of Yamaha pss 140 synthesizer. This is a good model it's a FM synthesizers. It got many songs , many cool rhythms,nice trumpets and it is working real nice.Here he states that it is important for power supply or else we don't need batteries.First thing we have to do is open the case and we can see the wires related to battery supply but he doesn't need batteries. Keep the case aside so that you can get free space. Remove the screws so that we can insert cables. we can see main chips, voice chips,you can see data lines on the main processor of the chip. Here he had to cut the data lines and solder the pavement here and put there. He also had 8 switches .Here you can see 8 data lines from the main chip in which 6 go to one point and two more go to another point.And when you see in the back side you can see two bridges. You have to cut the two bridges. You can see all data lines and now ill search some cables.