Steal this circuit, please!

Harry Bissell harrybissell at
Fri Jan 21 04:38:15 CET 2000

The poor maligned "Lytic"

Any lytic that gets hot is being beat to death with ripple current (the only
thing that makes them hot...) Its either
1) A shitty or ignorant design  ~or~
2) An informed trade off between cost and expected (to be less than eternal)

Film caps are better in high ripple / high voltage apps... If the size don't
kill you...

:^) Harry (uses 2800uF / 900V film cap and has never lost one !!!)

John E Blacet wrote:

> 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
> -------------------------
> blacet at

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