[sdiy] Prophet 5 dead output after ship...anyone?

[Bob Weigel]

And thanks Barry.  Yes that would be likely if they are mounted in a way 
where they are vibration coupled to the case as is likely given the heat 
sink location there.  This commonly happens on Mackie 1400i amps...even 
though they are rather dense which you would think would kind of keep 
them from vibrating around much.., just from travelling in vehicles. The 
'sub board' sink mounted transistors break legs quite commonly. -Bob

Barry Klein wrote:

>There are 78xx/79xx regulators mounted to the rear chassis that typically
>have their legs break with shipment.  Probably you have 5V but not +/-15V.
>I typically buy these for $500  :-)
>
>
>Barry
>
>
>-----Original Message-----
>From: owner-synth-diy at dropmix.xs4all.nl
>[mailto:owner-synth-diy at dropmix.xs4all.nl] On Behalf Of Tim Parkhurst
>Sent: Tuesday, June 14, 2005 4:23 PM
>To: analogue list; synthdiy
>Subject: RE: [sdiy] Prophet 5 dead output after ship...anyone?
>
>  
>
>>-----Original Message-----
>>From: Bob Weigel [mailto:sounddoctorin at imt.net]
>>Sent: Tuesday, June 14, 2005 12:00 AM
>>To: analogue list; synthdiy
>>Subject: [sdiy] Prophet 5 dead output after ship...anyone?
>>
>>I sent a P5 over to GB that had worked perfect here the whole way.  I
>>tested it one last time after doing a little touch up on the key
>>allignment or something as I recall, then boxed it up and shipped it
>>with a great box design that had it floating on white foam end blocks
>>pretty well isolated all the way there.
>>He said it seems to be responding to patch changes and when you
>>hit
>>keys the LED flickers a bit as it does when MIDI information comes in.
>>But no sound out.  I told him to verify that it's getting to the
>>master
>>volume with a headphone amp or such but..anybody have any thoughts on
>>what likely happened. He didn't see any wires falling off or anything.
>>He tried programming a patch with filter open etc. no go-Bob
>>
>>    
>>
>
>Hi Bob, 
>
>If you think the your customer is capable of doing it, I'd suggest having
>him open up the P5 and disconnecting/reseating every cable connection he can
>get to. Might also be worth it to press on any socketed ICs to make sure
>they're properly seated (after hooking up a wrist strap first, or at least
>always keeping one hand on a metal part of the chassis). I had two synths go
>belly up on me in the last month, and both were fixed by
>disconnecting/reseating everything. 
>
>Basically, I think no matter how well the P5 was packed, the internals still
>get shaken around during transport. I'd bet Harry's next paycheck that it's
>no more than a bad connection. MAYBE it's an 'iffy' solder joint that got
>wiggled a little too hard on the trip across the pond, but the
>socket/connector check would certainly be easier for the customer to do. And
>finally, though this is a bit 'out there', perhaps a PS trimmer got knocked
>around enough to put one of the supplies too far out of whack. Maybe have
>the customer check the supply voltages too. Maybe. 
>
>Anyway, just my $US0.02
>
>
>
>Tim (surely you didn't think I was going to bet my OWN paycheck) Servo
>
>"And don't call me 'Shirley'" - Leslie Nielsen
>
>
>
>
>
>  
>