Vintage Simmons Drums (UK) Users Group

> The chips that are missing are marked iC37 & IC38. Can anyone verify 
> that these are curtis chips & what the curtis part number is ? 

They're Curtis CEM3394s.  There should be one for each tom.  Does one of the
toms work?  There is also a CEM3372, but that's a filter for the snare.  
CEM3394s are not easy to find.  Paul "MOTM" Schreiber keeps most Curtis chips, 
but he's out of 3394s.  You should be able to get the data sheet off his site 
though.

Do you know why the 3394s were removed?  Before you replace them, check the 
power supply.  Curtis chips are very vulnerable to excess voltage.  The
PSU should give +15v, +5v and -6.5v.  I had a PSU go bad in an SDS1000
(cut down SDS9 in a rack), and it took out the Curtis chips and a random
selection of other devices.  Sound familiar?

I have schematics, but my scanner is dying.  If you're not too far away, I
might consider photocopying and posting them for you...


Steve

Yes, either the chips were blown out of their sockets or someone de-soldered 
them and earned big bucks on Ebay!

electronically yours, jesper
- -- --- ---- ----- ---- --- -- -
www.electronic-obsession.se


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

From: "Steve Ridley" <spr@...>
To: <Simmons_Drums@yahoogroups.com>
Sent: Tuesday, September 20, 2005 2:13 PM
Subject: RE: [Simmons Drums] Re: sds9 info wanted


>
>> The chips that are missing are marked iC37 & IC38. Can anyone verify
>> that these are curtis chips & what the curtis part number is ?
>
> They're Curtis CEM3394s.  There should be one for each tom.  Does one of 
> the
> toms work?  There is also a CEM3372, but that's a filter for the snare.
> CEM3394s are not easy to find.  Paul "MOTM" Schreiber keeps most Curtis 
> chips,
> but he's out of 3394s.  You should be able to get the data sheet off his 
> site
> though.
>
> Do you know why the 3394s were removed?  Before you replace them, check 
> the
> power supply.  Curtis chips are very vulnerable to excess voltage.  The
> PSU should give +15v, +5v and -6.5v.  I had a PSU go bad in an SDS1000
> (cut down SDS9 in a rack), and it took out the Curtis chips and a random
> selection of other devices.  Sound familiar?
>
> I have schematics, but my scanner is dying.  If you're not too far away, I
> might consider photocopying and posting them for you...
>
>
> Steve
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>

Thanks for the info

I believe the chips have been taken for use elsewhere.  There are 
switches missing which look like they have been taken to repair 
something else, so I kind of think this may have been the case with 
the chips.  DOes anyone have a source for the CEM3394 ?

One other thing I`ve noticed is that there is an orange wire coming 
from the PSU board on one corner.  The other end has become 
detached.  Does anyone know where this should connect to ?

Steve, The diagrams would be useful.  I`m based in the UK. I don`t 
know if thats too far away.

thanks again 
regards Rob

--- In Simmons_Drums@yahoogroups.com, <jesper@e...> wrote:
> Yes, either the chips were blown out of their sockets or someone de-
soldered 
> them and earned big bucks on Ebay!
> 
> electronically yours, jesper
> - -- --- ---- ----- ---- --- -- -
> www.electronic-obsession.se
> 
> 
> ----- Original Message ----- 
> From: "Steve Ridley" <spr@s...>
> To: <Simmons_Drums@yahoogroups.com>
> Sent: Tuesday, September 20, 2005 2:13 PM
> Subject: RE: [Simmons Drums] Re: sds9 info wanted
> 
> 
> >
> >> The chips that are missing are marked iC37 & IC38. Can anyone 
verify
> >> that these are curtis chips & what the curtis part number is ?
> >
> > They're Curtis CEM3394s.  There should be one for each tom.  Does 
one of 
> > the
> > toms work?  There is also a CEM3372, but that's a filter for the 
snare.
> > CEM3394s are not easy to find.  Paul "MOTM" Schreiber keeps most 
Curtis 
> > chips,
> > but he's out of 3394s.  You should be able to get the data sheet 
off his 
> > site
> > though.
> >
> > Do you know why the 3394s were removed?  Before you replace them, 
check 
> > the
> > power supply.  Curtis chips are very vulnerable to excess 
voltage.  The
> > PSU should give +15v, +5v and -6.5v.  I had a PSU go bad in an 
SDS1000
> > (cut down SDS9 in a rack), and it took out the Curtis chips and a 
random
> > selection of other devices.  Sound familiar?
> >
> > I have schematics, but my scanner is dying.  If you're not too 
far away, I

> > might consider photocopying and posting them for you...
> >
> >
> > Steve
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >

Having had another look the 3rd 3394 is also missing.

--- In Simmons_Drums@yahoogroups.com, Steve Ridley <spr@s...> wrote:
> 
> > The chips that are missing are marked iC37 & IC38. Can anyone 
verify 
> > that these are curtis chips & what the curtis part number is ? 
> 
> They're Curtis CEM3394s.  There should be one for each tom.  Does 
one of the
> toms work?  There is also a CEM3372, but that's a filter for the 
snare.  
> CEM3394s are not easy to find.  Paul "MOTM" Schreiber keeps most 
Curtis chips, 
> but he's out of 3394s.  You should be able to get the data sheet 
off his site 
> though.
> 
> Do you know why the 3394s were removed?  Before you replace them, 
check the 
> power supply.  Curtis chips are very vulnerable to excess voltage.  
The
> PSU should give +15v, +5v and -6.5v.  I had a PSU go bad in an 
SDS1000
> (cut down SDS9 in a rack), and it took out the Curtis chips and a 
random
> selection of other devices.  Sound familiar?
> 
> I have schematics, but my scanner is dying.  If you're not too far 
away, I

> might consider photocopying and posting them for you...
> 
> 
> Steve

I'd suggest buying a complete working SDS-9 is worth more than the trouble - 
use this for spares!

electronically yours, jesper
- -- --- ---- ----- ---- --- -- -
www.electronic-obsession.se


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

From: "flinnrob" <flinnrob@...>
To: <Simmons_Drums@yahoogroups.com>
Sent: Tuesday, September 20, 2005 8:02 PM
Subject: [Simmons Drums] Re: sds9 info wanted


> Having had another look the 3rd 3394 is also missing.
>
> --- In Simmons_Drums@yahoogroups.com, Steve Ridley <spr@s...> wrote:
>>
>> > The chips that are missing are marked iC37 & IC38. Can anyone
> verify
>> > that these are curtis chips & what the curtis part number is ?
>>
>> They're Curtis CEM3394s.  There should be one for each tom.  Does
> one of the
>> toms work?  There is also a CEM3372, but that's a filter for the
> snare.
>> CEM3394s are not easy to find.  Paul "MOTM" Schreiber keeps most
> Curtis chips,
>> but he's out of 3394s.  You should be able to get the data sheet
> off his site
>> though.
>>
>> Do you know why the 3394s were removed?  Before you replace them,
> check the
>> power supply.  Curtis chips are very vulnerable to excess voltage.
> The
>> PSU should give +15v, +5v and -6.5v.  I had a PSU go bad in an
> SDS1000
>> (cut down SDS9 in a rack), and it took out the Curtis chips and a
> random
>> selection of other devices.  Sound familiar?
>>
>> I have schematics, but my scanner is dying.  If you're not too far
> away, I
>> might consider photocopying and posting them for you...
>>
>>
>> Steve
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>