[sdiy] Roland SH-101 power supply sorrows

[Scott Nordlund]

I'd guess (though I don't have an SH-101) that L1 is just a choke that reduces high frequency noise, and it's frying because something else is shorted.  In that case, it would be inline with the unregulated input power.  As long as it isn't completely open, you can worry about it later, or just replace it with something that serves a similar purpose.

> Date: Mon, 24 Aug 2009 10:18:14 +0200
> From: fanwander at mnet-online.de
> To: billbigrig at yahoo.com
> Subject: Re: [sdiy] Roland SH-101 power supply sorrows
> CC: Synth-diy at dropmix.xs4all.nl
> 
> Hello Rig
> 
>>  I have a Roland SH-101 that does not work. While troubleshooting, the power supply transistor TR@ (or TR1, the big one in any event) had a crack in it. The big problem is component L1. L1 does not show on the schematic or parts list. It would be nice to identify this part as it was smoking a great deal and I'm sure needs replacement. Anybody know what this part is and it's value? Thank you.
> Where should this L1 be on the pcb?
> http://fa.utfs.org/diy/rolandsh101/Roland-SH101-Service-Manual.pdf
> -> page 8 is the pcb
> 
> Florian
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