Sunday, 24 January 2010
Replace Ram battery Resurrection...Yamaha DX11
I got given this synth a while ago (thats right for free!) in a non working state...when I turned it on it proclaimed on its little LCD "cng ram bat"..so thats what I did. I've had to do this on a couple of old bits of kit in my arsenal now and invariably when you find the ram backup battery it is soldered to the pcb via solder tags that are spot welded to the battery..no exception in this case (see pic below). It's sometimes hard to find the required battery with the solder tags welded on so most of the time a better option is to wire a small battery holder to the original pcb points that can hold a comparable battery.
So this battery is a cr2032 which is pretty common but I've still soldered in a battery holder so that in ten years time when I need to do this again I can just clip a battery in without breaking out the soldering iron. For those who may need to do this job in the future and stumble here...it's not immediately apparent where the ram battery is once you get the back off of this synth...this picture shows the board (big green tick) and the corner (green spot) where it is..you need to remove the six screws holding this board to the frame and I found I didn't have to undo all the connectors to the board just the one labelled "cnd1"..that allowed me to lift the board to a workable angle
That last pic shows how I attached a couple of short leads to the points where I'd removed the old battery and connected the new battery holder (actually one I'de scavenged from an old computer motherboard.. most of these use cr2032 to backup the bios ram in battery holders) I taped this into a little space I found so it wouldn't rattle and then put it all back together.
Then I've got nothing else done apart from playing around with it all afternoon! It's a great synth..people overlook them as they are interested in the DX7 which has 6 operators instead of the DX11's 4 but then the DX11 has 6 different waveforms available for each operator (the DX7 only has sin waves) so it's a pretty even match in my humble opinion and can with experimentation create some glorious digital fm goodness.