[sdiy] Siel OR400 power supply busted

[M Maeghan Skala]

I got the power supply working :)

But the synth isn't working. I'm gonna guess that even though the power wasn't being distributed to the rest of the circuitry, that when the short circuit happened … it arced and friend some components.

THe synth is now turning on, and getting the proper voltages (not perfect but .1 off on some of the leads) … no sound. One of the chips, the LM13700 has a broken leg but according to Bob Wiegel over on sounddoctorin, that would take out the brass section. 

Here's my question: should I consider the synth dead? or is this something that can be fixed? 

I did see an arc flash beneath the enclosure when this happened.

Where should I start testing from here? I did check all the ribbon cables, they don't have any broken wires.

thanks for the yall's patience and help with me

cheers ~ maeghan


On Aug 3, 2013, at 5:45 PM, M Maeghan Skala <synth.diy at pulsewidthmod.com> wrote:

> ok, i will this evening … i'm taking a nap, if I had left the synth alone this would have never happened.
> 
> thank you :)
> 
> On Aug 3, 2013, at 5:43 PM, Paul Anderson <wackyvorlon at me.com> wrote:
> 
>> Make sure you check the resistance. You will still read 120 volts across an open primary. Voltage is potential difference, it doesn't require flowing current to be present. 
>> 
>> 
>> Sent from my iPhone
>> 
>> On 2013-08-03, at 5:20 PM, M Maeghan Skala <synth.diy at pulsewidthmod.com> wrote:
>> 
>>> I was able to measure 121 on the wire of the primary, on both of them … so power was going into the transformer, just not coming out of it
>>> 
>>> 
>>> On Aug 3, 2013, at 3:14 PM, ASSI <Stromeko at nexgo.de> wrote:
>>> 
>>>> On Saturday 03 August 2013, 14:29:43, M Maeghan Skala wrote:
>>>>> :( … after switching out some components and much troubleshooting, i
>>>>> :finally got the proper readings from the board.
>>>> 
>>>> Good.
>>>> 
>>>>> I plug all the ribbon cables in and plug it into an amp … no power
>>>>> the transformer's primary wires coming from the connection terminal are
>>>>> both reading 121, but the secondaries … nothing, O
>>>>> It's not the fuse, I checked that … also, i don't think the primaries
>>>>> would be getting power if the fuse was busted.
>>>> 
>>>> Some transformers have a thermal fuse integrated into their windings.  
>>>> Getting no reading at all from the secondaries must mean that the primary 
>>>> doesn't get power one way or the other.  Assuming that you can disconnect 
>>>> both the primary and the secondary wiring from the inlet and circuit, please 
>>>> test with a small DC voltage (diode or connectivity test on your typical 
>>>> DVM) that all coils are low-resistance.  If you can measure the resistance, 
>>>> then you should do this as well.
>>>> 
>>>>> This is so frustrating, i finally got the right power readings … and this
>>>>> :(
>>>> 
>>>> Well, you've certainly had exceptionally bad luck so far, it must be getting 
>>>> better any time now.   :-)
>>>> 
>>>> 
>>>> 
>>>> Regards,
>>>> Achim.
>>>> -- 
>>>> +<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+
>>>> 
>>>> SD adaptations for KORG EX-800 and Poly-800MkII V0.9:
>>>> http://Synth.Stromeko.net/Downloads.html#KorgSDada
>>> 
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