In this video I replace the Yamaha DX7 power cable with a IEC C8 socket (If you are going to do this please be VERY careful as this is 110/220V and it can be very dangerous). It seems to be quite common in the DX7 that the cable, which is mounted directly in the chassis, gets broken at the case due to being bent. This is especially true if the unit has been carried in a flight case/bag. In this unit someone had replaced the cable earlier in a very poor manner and they did not mount the strain relief. This had caused the cable to scrape against the metal and the copper in the 220V cable was exposed! I had replaced this cable earlier and created a strain relief using vulcnanizing tape and some zip ties. But I thought it would be nice to replace the cable with a IEC C8 socket so the cable can be removed if it needs to be transported. I also removed the 110/220V switch as as this fell apart when removed the screws. I hardwired it to 220-240V.
I bought this DX7 as a repair project and it is pretty banged up due to having been used in a touring band so I didn’t bother very much about making an extremely clean mod.