[sdiy] Akai S612 power problems

[Adam Inglis]

Thanks Alan
I haven't made any current tests yet.
Yes, the +12 rail seems fine now. It's transistor series regulator is  
tapped before the 15 volt ICs, the 5 volt regs are after these.
Schematic here
http://www.adambaby.com/tempdownloads

When you say overloaded, you mean the current draw is too much for the  
pass transistors in the 5 volt reg circuit?

Sorry if I seem a bit thick, but I'm trying to understand a possible  
single cause for both 5 volt rails dropping. I'm thinking the problem  
lies in the PSU, given it's stormy history, but of course it may be on  
the load side.

Adam

On 04/10/2012, at 5:31 PM, Needham, Alan wrote:

> So the +/- 12v rails are OK when the =/_5v rails are sagging?
> Can you measure the current on these two rails?
> I am wondering if there is an overload on them...
>
>
> -----Original Message-----
> From: synth-diy-bounces at dropmix.xs4all.nl [mailto:synth-diy-bounces at dropmix.xs4all.nl 
> ] On Behalf Of Adam Inglis
> Sent: 04 October 2012 04:57
> To: *SYNTH DIY
> Subject: [sdiy] Akai S612 power problems
>
> replacing that, I
> get my 12 volts back, and checking all voltages again around the PCB
> is all good... until I hook it up, and again, the +/- 5 v rails are
> sagging.
>
>
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