Vintage Simmons Drums (UK) Users Group

The first thing I look @ is the output jack  on the pads. They might be 
dirty. Use some contact cleaner like DeOxit or Blue  Shower w/ a cottom swap to 
clean them. Double triggering sometimes indicates  that something is loose. Open 
your pads and check their piezo disc. It might not  be glued in place anymore. 
You may even have a detached wire that is just  resting where it was once 
soldered. When you strike a pad in this condition the  wire jumps off the piezo 
and triggers numerous times. The malfunction in the  brain is probably from a 
faulty memory backup  battery. Ni-cad batteries usually last 15 years. If  you 
got 20, consider yourself lucky. But beware. Cycling power through a worn  PCB 
mounted battery may cause it to explode and damage the board it's soldered  
to. This is something I learned the hard way w/ an SDS-7. As for your shells, 
it  sounds like you have some worn or broken plastic. Shells appear on Ebay US 
from  time to time. Senso may have a few in stock. He's a member of this 
groups so  contact him or check the links for his URL.


[Non-text portions of this message have been removed]

Thanks for your help with this!  I've never been inside the unit 
before and I don't want to mess it up worse than it already is.  
Please bear with me.  

First of all, is the Ni-Cad battery that thing mounted on the PCB 
surrounded by a white plastic sheath with a white cap? Is this model 
battery still available in stores after 20 years?  What is the 
easiest way to get the thing off and replace it?

Thanks again for your help.

Jeff


--- In Simmons_Drums@yahoogroups.com, sovereigng@a... wrote:
>
> The first thing I look @ is the output jack  on the pads. They 
might be 
> dirty. Use some contact cleaner like DeOxit or Blue  Shower w/ a 
cottom swap to 
> clean them. Double triggering sometimes indicates  that something 
is loose. Open 
> your pads and check their piezo disc. It might not  be glued in 
place anymore. 
> You may even have a detached wire that is just  resting where it 
was once 
> soldered. When you strike a pad in this condition the  wire jumps 
off the piezo 
> and triggers numerous times. The malfunction in the  brain is 
probably from a 
> faulty memory backup  battery. Ni-cad batteries usually last 15 
years. If  you 
> got 20, consider yourself lucky. But beware. Cycling power through 
a worn  PCB 
> mounted battery may cause it to explode and damage the board it's 
soldered  
> to. This is something I learned the hard way w/ an SDS-7. As for 
your shells, 
> it  sounds like you have some worn or broken plastic. Shells appear 
on Ebay US 
> from  time to time. Senso may have a few in stock. He's a member of 
this 

> groups so  contact him or check the links for his URL.
> 
> 
> [Non-text portions of this message have been removed]
>

Jeff,
    Try Maplin Electronics in England. They  have many odd pieces like these 
batteries. I managed to locate an appropriate  battery, though of a different 
shape, for my MTMs and SDS-7s. It took time to  locate on their site so be 
diligent.


[Non-text portions of this message have been removed]

sovereigng@... wrote:
> Jeff,
>     Try Maplin Electronics in England.

Sheesh, I'd have to go all the way to England?  Why wouldn't I just go 
to the one along the road?

Gordon.

Rather a shortsighted statement, don't you  think?
    Maplin has a secure website. Google  them. 


[Non-text portions of this message have been removed]

sovereigng@... wrote:
> Rather a shortsighted statement, don't you  think?
>     Maplin has a secure website. Google  them. 

My point is rather that there are branches of Maplins all over the UK, 
not just England.

Gordon.

Thank you. It's getting late here on the  east coast and I was beginning to 
worry that I wouldn't learn anything today.  You have enriched my life.


[Non-text portions of this message have been removed]

sovereigng@... wrote:
> Jeff,
>     Try Maplin Electronics in England. They  have many odd pieces like these 
> batteries. I managed to locate an appropriate  battery, though of a different 
> shape, for my MTMs and SDS-7s. It took time to  locate on their site so be 
> diligent.

Doesn't actually matter about the shape of the battery as long as it's 
the same type - read the label - and the same voltage.

If it has a NiCad on board it may need charged before you fit it, to 
avoid clobbering the usually fairly mickey-mouse charging circuits that 
synths have.  If it's a lithium battery it will just have a diode 
feeding power to the memory chips.

Gordon.

'Cause Simmons gear break instantly if repaired with vicious US components! 
;)

electronically yours, jesper - couldn't resist the temptation
- -- --- ---- ----- ---- --- -- -
www.electronic-obsession.se


----- Original Message ----- 

From: "Gordon JC Pearce" <gordon@...>
To: <Simmons_Drums@yahoogroups.com>
Sent: Tuesday, November 01, 2005 12:51 AM
Subject: Re: [Simmons Drums] New Member With A Question (2 Actually)


> sovereigng@... wrote:
>> Jeff,
>>     Try Maplin Electronics in England.
>
> Sheesh, I'd have to go all the way to England?  Why wouldn't I just go
> to the one along the road?
>
> Gordon.
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>

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?  

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.

Thanks,
Jeff

> 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.

> 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'd check the power supply very carefully first.  If there's 50/60Hz 
hum on it's output, that might repeatedly trigger all the voices repeatedly.
If you turn all the voices down, do you hear loud hum on the output?


Steve

Are these multitriggers sounding like heavy rain on a tin-roof? If it is so: We had a problem like this too (20 Years ago...). It was a capacitor leakage. We hooked an oscilloscope to the supply voltage busses and watched for ripples and ac (Note: If the supply is ok, you see only a straight line). We found them on +15 V power, the spikes occured in the same rhythm as the triggers. It was not one of the big capacitors of the power supply, a 10 mf blocker on one of the voiceboards was the bandit. The search took nearly a day. In your case, the 5V must be working fine, thats the reason why your midi is still ok. Check -15V and +15V for ac, and then check (desolder) every capacitor in the unit hooked up between the supplies and ground. Good luck. 

[Non-text portions of this message have been removed]