Vintage Simmons Drums (UK) Users Group

Hi look info at simmonsmuseum web site ..

Inviato da iPhone

> Il giorno 09 dic 2017, alle ore 17:48, sjgallos@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> ha scritto:
> 
> Can anyone tell me if the memory backup battery is a rechargeable battery or a primary cell?
> I need to replace it and the old battery doesn't have any markings on it that indicate the type. I wouldn't want to put a lithium battery in there if the board will try to charge it. I used to have a schematic but after 2 moves, I can't locate it.
> I know there are members that have schematics for the SDS9. I would be willing to buy a copy if anyone is interested.
> Also, back in 2013 "philmurr" posted a message about replacing batteries and said that for his SDS9, he replaced the RAM with an NVM version from Dallas semi but didn't provide a part number. Has anyone else done this?
> 
> Thanks,
> Steve
> 
> 
> 
>

Hi,
this a rechargeable battery 3,3V for the RAM(IC48).I have the schematic from a friend, but there is not the detail of the battery.
Regards.
Yves
    Le jeudi 14 décembre 2017 à 14:45:53 UTC+1, Cristiano Dal Cin cdalcin@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> a écrit :  
 
     
Hi look info at simmonsmuseum web site ..

Inviato da iPhone
Il giorno 09 dic 2017, alle ore 17:48, sjgallos@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> ha scritto:


    
Can anyone tell me if the memory backup battery is a rechargeable battery or a primary cell?
I need to replace it and the old battery doesn't have any markings on it that indicate the type. I wouldn't want to put a lithium battery in there if the board will try to charge it. I used to have a schematic but after 2 moves, I can't locate it.
I know there are members that have schematics for the SDS9. I would be willing to buy a copy if anyone is interested.
Also, back in 2013 "philmurr" posted a message about replacing batteries and said that for his SDS9, he replaced the RAM with an NVM version from Dallas semi but didn't provide a part number. Has anyone else done this?

Thanks,
Steve

The problem with replacing a NiCad battery with a NiMh battery is the charge circuit would be designed to provide a trickle charge of 1/10C. If you charge a NiMH battery at that rate for prolonged periods after it is fully charged, you will damage it (https://en.wikipedia.org/wiki/Nickel%E2%80%93metal_hydride_battery).
In this case, the charge circuit is an 18 ohm resistor tied to 5V. Assuming a fully charged cell floats to 1.4V, the battery pack will end up at 4.2V which will yield a charge current of ~44mA. So, at a minimum,  if the battery capacity is 440mAh or less, consider replacing it.
I would not recommend leaving you unit on for prolonged periods (10- 20 hours)
I ended up replacing mine with a NiCad battery from a phone I no longer use.


--------------------------------------------
On Mon, 12/18/17, Ewan Colsell ewanuno@... [Simmons_Drums] <Simmons_Drums@yahoogroups.com> wrote:

 Subject: Re: [Simmons Drums] Re: SDS9 backup battery and schematic.
 To: Simmons_Drums@yahoogroups.com
 Date: Monday, December 18, 2017, 6:14 PM
     
       
       
       i replaced the battery in my
 sds9 with a 3.6v nimh battery. the original was a nicad, but
 the nimh is fine.
 the battery i used was a
 replacement for a wireless phone if i remember correctly.
 
 ewan.
 On 16 December 2017 at
 07:04, Realm Steel realmsteel@...
 [Simmons_Drums] <Simmons_Drums@yahoogroups.com>
 wrote:
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
  
 
 
 
   
 
 
     
       
       
       I replaced my battery about 5
 years ago.Do a google search for "NI-MH 3.6
 V/80mAh".I may have bought from
 Newark.
 Thank
 you,
 Realm
 Steel
 
 
 
     
      
 
     
     
 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
     
      
 
     
     
 
 
 
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