Any AA size "old school" nicad will do. You'll need 3 and a soldering iron to do it. The reason for old generation nicad is that the cart has no fancy charging circuit (as most new types need to charge properly) just an 18ohm resistor to restrict current and a diode. When fitting the new ones make sure you check the polarity as you connect them. Take note that Simmons recommended you plug the cart in once a month for a few hours to recharge the battery.
--- In Simmons_Drums@yahoogroups.com, Chris Cronin <gushi1@...> wrote:
>
> Whilst we're on the subject of the memory cart, I happen to have picked up an original over the past few weeks. I need to change the batteries, can anyone recommend a suitable replacement?
>
> Thanks
>
>
> ________________________________
> From: philmurr <philmurr@...>
> To: Simmons_Drums@yahoogroups.com
> Sent: Tuesday, 13 August 2013, 12:50
> Subject: [Simmons Drums] Re: Memory cart clone update.
>
>
>
> Â
> A schoolboy error :-(
>
> I think there are many reasons for errors on schematics:-
>
> 1) As a company they were very experimental, and didn't always follow best practice updating documents (how many of them that you've seen have hand-drawn/unreadable changes on them?)
>
> 2) Some of the schematics that are out there have come from various sources, and there's nothing to say that they're the most up to date ones, or ones that match the hardware we have. Even the SDS3 schematics are full of errors, and that's a very simple circuit !
>
> 3) As you say, most bits of Simmons kit have wire / component mods (for example I've an internal service note that says the latest pcb design for the SDE has a chip laid out backwards, that meant they had to make a piggy-back board to make it work !). These guys weren't using foolproof CAD tools to design the stuff !
>
> It makes it a little more of a "challenge" to get stuff working again. I don't think there was anyone genuinely incompetent or out to ruin his business. It's just one of the problems you get when you leave Engineers in charge of products (and that's not meant to be rude about Engineers, after all, I'm one...)
>
> Good luck with the memory cart, at least it will look like a genuine Simmons product with all its mods :-)
>
> --- In Simmons_Drums@yahoogroups.com, "Richard" <warlandr63@> wrote:
> >
> > Well, I'll start by simply saying I have committed the cardinal sin when dealing with the technical side of Simmons gear....DON'T ASSUME ANYTHING IS AS IT IS DRAWN. Once again, the schematics simply don't match what is layed out on the original PCB. I'm kicking myself at the moment, need to alter a few things and work out if I can change the boards I have (ie cut a track or 2 and add some connections....those who have ever looked inside Simmons gear will know what I mean..lol)or get some more run.
> >
> > Dave Simmons (if he ever visits and reads this stuff) I have come to the conclusion either;
> >
> > 1) Someone inside your old business was out to ruin you...or
> >
> > 2) You were paying for some engineering staff who were verging on incompetent!!
> >
> > I have worked on enough of this gear to know just how bad some of the designs are. Don't get me wrong, the concepts and sound are second to none but the implementation of the hardware is truly bad in some cases. The SDS7 is probably the worst example. They are SO temperamental I can't believe they were built the way they were with the intention they would be carted around and gigged. You just have to look at them the wrong way and they stop working. The sockets for the cards are simply atrocious. God help anyone who has lost the little plastic card key in any slots...the board can misalign when plugged in or moved (vibration) and it WILL kill the board. The case design is not very rigid, all the cards use this non rigid case for support. Mis-handle the unit and you apply stress to all the PCB's leading to track/connection fractures. Simply wrong!!
> >
> > Well now I've got that off my chest I'll go back to burying my boot up my own arse.
> >
> > Be patient, I'll have a look at what I can do then get back to you.
> >
> > --- In Simmons_Drums@yahoogroups.com, "Richard" <warlandr63@> wrote:
> > >
> > > Added a couple of extra pics as I put together the first unit so I can test it is all good.
> >
>
>
>
>
> [Non-text portions of this message have been removed]
>