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Thread

SDS7 repairs

SDS7 repairs

2011-09-16 by WT

So,

my SDS7 died a few weeks ago.

It has 12 modules and runs very hot. The rectifier for the +5V made a noise 
and the display flickered in and out.

I\ufffdve removed all modules and the CPU starts and run with no problem. 
Reseating modules one at a time works fine but the more modules that are 
connected, the more there is noise on the +5V rail ( no kidd....lol ). The 
VCO\ufffds sound garbled and the audio output has hum.

I have replaced the capacitor on the +5V rail but there is still around 1V 
AC half wave noise on it. Both before the regulator and after the regulator. 
This leads me to believe that I need to replace the rectifier bridge with 
one that can output more current.

Does anyone have any suggestion for a suitable one ?

WT

SV: [Simmons Drums] SDS7 repairs

2011-09-17 by KW

i'm really sorry to hear this, hope help comes soon buddy!

/k



________________________________
Från: WT <waveterm@...>
Till: Simmons_Drums@yahoogroups.com
Skickat: fredag, 16 september 2011 22:52
Ämne: [Simmons Drums] SDS7 repairs


  
So,

my SDS7 died a few weeks ago.

It has 12 modules and runs very hot. The rectifier for the +5V made a noise 
and the display flickered in and out.

I´ve removed all modules and the CPU starts and run with no problem. 
Reseating modules one at a time works fine but the more modules that are 
connected, the more there is noise on the +5V rail ( no kidd....lol ). The 
VCO´s sound garbled and the audio output has hum.

I have replaced the capacitor on the +5V rail but there is still around 1V 
AC half wave noise on it. Both before the regulator and after the regulator. 
This leads me to believe that I need to replace the rectifier bridge with 
one that can output more current.

Does anyone have any suggestion for a suitable one ?

WT 


 

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

Re: SV: [Simmons Drums] SDS7 repairs

2011-09-17 by Jacquot.Patrice@free.fr

you can send me a pic of it  so I could look if I have one ?
Tell me via private mail.
good luck,
Patrice.



----- Mail d'origine -----
De: KW 
À: Simmons Drums 
Envoyé: Sat, 17 Sep 2011 07:26:24 +0200 (CEST)
Objet: SV: [Simmons Drums] SDS7 repairs
















 



  


    
      
      
      i'm really sorry to hear this, hope help comes soon buddy!



/k



________________________________

Från: WT <waveterm@...>

Till: Simmons_Drums@yahoogroups.com

Skickat: fredag, 16 september 2011 22:52

Ämne: [Simmons Drums] SDS7 repairs



  

So,



my SDS7 died a few weeks ago.



It has 12 modules and runs very hot. The rectifier for the +5V made a noise 

and the display flickered in and out.



I´ve removed all modules and the CPU starts and run with no problem. 

Reseating modules one at a time works fine but the more modules that are 

connected, the more there is noise on the +5V rail ( no kidd....lol ). The 

VCO´s sound garbled and the audio output has hum.



I have replaced the capacitor on the +5V rail but there is still around 1V 

AC half wave noise on it. Both before the regulator and after the regulator. 

This leads me to believe that I need to replace the rectifier bridge with 

one that can output more current.



Does anyone have any suggestion for a suitable one ?



WT 



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




    
     

    
    






  









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

Re: SDS7 repairs

2011-09-18 by gordonjcp

> I have replaced the capacitor on the +5V rail but there is still around 1V 
> AC half wave noise on it. Both before the regulator and after the regulator. 
> This leads me to believe that I need to replace the rectifier bridge with 
> one that can output more current.

The diode bridge has failed, with one diode going short-circuit.  This is surprisingly common - far more than failed capacitors which never go unless they get cooked off by a shorted rectifier!

Any very large diode bridge will do.  I would tend to make one up out of discrete 10A 400V diodes, but only because I've got hundreds of them to get through ;-)

Gordon MM0YEQ

Re: SDS7 repairs

2011-09-18 by WT

Yep,

rectifier is broken.

Should I replace it with an identical or find one that can handle more current ?

Any tips on a suitable one ?

WT
Show quoted textHide quoted text
  ----- Original Message ----- 
  From: Michael Buchner 
  To: waveterm@... 
  Sent: Saturday, September 17, 2011 2:33 AM
  Subject: Re: SDS7 repairs


  It looks like one of the rectifyer diodes is down. You can check this with a multimeter, but the rectifyer is so cheap that it is no thing to replace it.
  The problem is happening only under load (massive power consumption). So, my bet is: Not the cap but the rectifyer (semi-conductor).
  Best
  Michael

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

Re: [Simmons Drums] SDS7 repairs

2011-09-18 by WT

Thanks mate !

WT
Show quoted textHide quoted text
----- Original Message ----- 
From: "KW" <memtechlist@...>
To: <Simmons_Drums@yahoogroups.com>
Sent: Saturday, September 17, 2011 7:26 AM
Subject: SV: [Simmons Drums] SDS7 repairs


i'm really sorry to hear this, hope help comes soon buddy!

/k



________________________________
Fr�n: WT <waveterm@...>
Till: Simmons_Drums@yahoogroups.com
Skickat: fredag, 16 september 2011 22:52
�mne: [Simmons Drums] SDS7 repairs



So,

my SDS7 died a few weeks ago.

It has 12 modules and runs very hot. The rectifier for the +5V made a noise
and the display flickered in and out.

I�ve removed all modules and the CPU starts and run with no problem.
Reseating modules one at a time works fine but the more modules that are
connected, the more there is noise on the +5V rail ( no kidd....lol ). The
VCO�s sound garbled and the audio output has hum.

I have replaced the capacitor on the +5V rail but there is still around 1V
AC half wave noise on it. Both before the regulator and after the regulator.
This leads me to believe that I need to replace the rectifier bridge with
one that can output more current.

Does anyone have any suggestion for a suitable one ?

WT




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



------------------------------------

Yahoo! Groups Links

Re: SV: [Simmons Drums] SDS7 repairs

2011-09-18 by WT

Installed now is an RS 261-491

http://se.rs-online.com/web/cpd/0261491/?searchTerm=261-491

WT
Show quoted textHide quoted text
----- Original Message ----- 
From: <Jacquot.Patrice@...>
To: "Simmons Drums" <Simmons_Drums@yahoogroups.com>
Sent: Saturday, September 17, 2011 4:16 PM
Subject: Re: SV: [Simmons Drums] SDS7 repairs


you can send me a pic of it  so I could look if I have one ?
Tell me via private mail.
good luck,
Patrice.



----- Mail d'origine -----
De: KW
�: Simmons Drums
Envoy�: Sat, 17 Sep 2011 07:26:24 +0200 (CEST)
Objet: SV: [Simmons Drums] SDS7 repairs


























      i'm really sorry to hear this, hope help comes soon buddy!



/k



________________________________

Fr�n: WT <waveterm@...>

Till: Simmons_Drums@yahoogroups.com

Skickat: fredag, 16 september 2011 22:52

�mne: [Simmons Drums] SDS7 repairs





So,



my SDS7 died a few weeks ago.



It has 12 modules and runs very hot. The rectifier for the +5V made a noise

and the display flickered in and out.



I�ve removed all modules and the CPU starts and run with no problem.

Reseating modules one at a time works fine but the more modules that are

connected, the more there is noise on the +5V rail ( no kidd....lol ). The

VCO�s sound garbled and the audio output has hum.



I have replaced the capacitor on the +5V rail but there is still around 1V

AC half wave noise on it. Both before the regulator and after the regulator.

This leads me to believe that I need to replace the rectifier bridge with

one that can output more current.



Does anyone have any suggestion for a suitable one ?



WT



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

























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



------------------------------------

Yahoo! Groups Links

Re: [Simmons Drums] Re: SDS7 repairs

2011-09-18 by WT

Yeah, I\ufffdve seen this before in a couple of PPG Wave\ufffds and a few other 
devices.

There\ufffds not a lot of to get in there and do such a mod. I think just 
replacing it with a similar one will be a big hassle due to the 
construction. Getting the card out means stripping the whole mainframe down 
to its bare minimum.

WT

----- Original Message -----
Show quoted textHide quoted text
From: "gordonjcp" <gordon@...>
To: <Simmons_Drums@yahoogroups.com>
Sent: Sunday, September 18, 2011 2:38 PM
Subject: [Simmons Drums] Re: SDS7 repairs


>
>> I have replaced the capacitor on the +5V rail but there is still around 
>> 1V
>> AC half wave noise on it. Both before the regulator and after the 
>> regulator.
>> This leads me to believe that I need to replace the rectifier bridge with
>> one that can output more current.
>
> The diode bridge has failed, with one diode going short-circuit.  This is 
> surprisingly common - far more than failed capacitors which never go 
> unless they get cooked off by a shorted rectifier!
>
> Any very large diode bridge will do.  I would tend to make one up out of 
> discrete 10A 400V diodes, but only because I've got hundreds of them to 
> get through ;-)
>
> Gordon MM0YEQ
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

Re: [Simmons Drums] Re: SDS7 repairs

2011-09-21 by WT

Arschel !!!

Changed the rectifier for a bigger 4A one and it made it worse.

Now I have ripple on +15V and on -5V. Sigh.....

Will change the +5V Regulator.

WT - Not happy....

----- Original Message -----
Show quoted textHide quoted text
From: "WT" <waveterm@...>
To: <Simmons_Drums@yahoogroups.com>
Sent: Sunday, September 18, 2011 2:56 PM
Subject: [Simmons Drums] Re: SDS7 repairs


> Yep,
>
> rectifier is broken.
>
> Should I replace it with an identical or find one that can handle more 
> current ?
>
> Any tips on a suitable one ?
>
> WT
>
>  ----- Original Message ----- 
>  From: Michael Buchner
>  To: waveterm@...
>  Sent: Saturday, September 17, 2011 2:33 AM
>  Subject: Re: SDS7 repairs
>
>
>  It looks like one of the rectifyer diodes is down. You can check this 
> with a multimeter, but the rectifyer is so cheap that it is no thing to 
> replace it.
>  The problem is happening only under load (massive power consumption). So, 
> my bet is: Not the cap but the rectifyer (semi-conductor).
>  Best
>  Michael
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

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