> I need to know the exact type of Ni-cad battery (volts, milliamps,
> etc) to use and how does it draw power to recharge. Let me know if
> this is what your battery looks like: it is wrapped in white plastic
> with a white plastic cap. There are 2 posts that slot into the PCB
> and then another arm that comes out of the PCB that extends over the
> top of the battery. I had to dig under the arm to free it from the
> battery. I also had to pry the 2 posts from the PCB (I'm afraid that
> I may have left a little piece of the post in the PCB). The battery
> itself is made up of 2 separate cells that are soldered together.
> Does this sound right?
It might not be a Ni-Cad, it might be a Lithium battery or similar. I
know that Lithium batteries seem to be far more common in synthss.
Lithium batteries seem to have a cell voltage of around 2v - more than
normal alkaline batteries which are around 1.6-1.7 volts. Basically you
want to keep the power to the memory ICs somewhere about 3-5 volts. I
found that three AA-size alkaline batteries keep the memory up just nicely
in my SDS-7.
The power will be fed through two diodes - one to stop the batteries
trying to power the whole +5 line, and one to stop the +5 line trying to
charge the batteries.
> Also, maybe somebody can help with THIS problem: When I turn the
> unit on, all of the drums start playing by themselves simultaneously
> as fast as they can go. I've taken the battery out and it is still
> happening. There is nothing I've found that will stop this. At
> this point, the unit is still great for MIDI but I can't use the
> internal sounds at all. Also, is it right that the unit really
> heats up after being on for 1/2 hour? Any help would be appreciated.
I have no idea about this triggering thing, but it may be something to do
with the trigger inputs. Possibly severe ripple from the PSU outputs, but
I'd expect that to cause other problems (loud hum on output).
My SPM8:2 gets incredibly hot after being on for an hour or so.
Gordon.