Adventures in creating and destroying sounds
RSS icon Home icon
  • Installing a New Battery in a Yamaha DX7

    Posted on September 26th, 2009 Bob 36 comments

    I recently had the chance to replace the battery in a Yamaha DX7 Synthesizer. The manual for the DX7 states that the battery should last for 3 to 5 years and it was well past that time. I first thought that I could just run down to Walgreens and pick up a “button” style battery and pop it in but after poking around on the Web, I found out that the DX7 uses a special kind of CR2032 battery with solder leads mounted on it. I found a suitable battery through Mouser (part number 614-CR2032FH-MFR). To replace the battery you basically have to take the whole synth apart, but Yamaha tries to make the procedure as painless as possible.

    I found some very helpful instructions through Dave Benson’s DX7 Page (also archived here) for replacing the battery. These instructions were spot-on!

    There were a couple of things I noticed while disassembling the synth.

    1. The connector labeled C6 on the main board is not connected to anything.
    2. The main board was a little difficult to remove from the chassis after all screws and connectors were out. There are two tabs that are used to mount keyboard. You have to angle the main board between these tabs and the back of the chassis to lift the board out. Be careful when doing this!
    3. To remove the old battery, I used a solder sucker to get rid of most of the old solder which makes it easier for the old battery to pry up and out.
    4. The battery evidently had been replaced before. There was a service sticker from some repair shop on the back of the unit. The trace between the battery’s positive lead and the next component (which is a diode) had been severed. I had to solder in a short jumper over the trace to fix it.

    Overall, replacing the battery was not a difficult task but somewhat time consuming. Have fun!

    You can click on the images below to get a larger image:

    Yamaha DX7 open with keyboard in place

    Yamaha DX7 open with keyboard in place

    Yamaha DX7 close-up of connector C6

    Yamaha DX7 close-up of connector C6

    Yamaha DX7 open with keyboard removed

    Yamaha DX7 open with keyboard removed

    Yamaha DX7 main board

    Yamaha DX7 main board

    Yamaha DX7 solder side of main board near battery

    Yamaha DX7 solder side of main board near battery