Steal this circuit, please!

[John E Blacet]

Digi-Key PN F2000; Littlefuse 60R010 for less than 100 mA.

As for the"20 year life span" of electrolytics, I'm hopeful that todays
caps are better made than those of the past. A common rating is 2000
hours at 105 C which is of course damn hot and not a likely synth
working condition. 

I do have experience with a switching power supply in a VCR that went
belly up after about 8 years of regular use. The caps actually got quite
hot in use. IMHO, the power supply was on the edge of being adequate for
the task, as it always ran very hot (thanks, Sony). After replacing the
caps, the VCR is back in operation. Power supply caps really are the
ones that take the abuse and are the most likely to fail.

The film cap route is pretty impractical for 10 to 100 uF caps. There is
plenty of gear out there with 20+ year old electrolytics, still working
fine. 

Of course the whole area of archivial electronics is one that deserves
some attention in this "throw it away and buy a new one" economy. I
build stuff to last as long as possible given the constraints of
economics and board space and perhaps most importantly, the MTBF factor
of having many components required to work together properly.
The ease of repair of components that are likely to fail first is also a
design concern.

Regards.
-------------------------
John Blacet
Blacet Research Music Electronics
http://www.blacet.com
-------------------------
blacet at metro.net