[sdiy] Updated Schematics of Rene/Wasp Hybrid

[René Schmitz]

harry bissell wrote:

> This gets to be a philosophical discussion.  Although the cap will not 
> likely fail, its operation
> is not guaranteed by design either. I can say that many many many 
> designers have gotten away
> with it. OTOH I think this is why the advice "replace all the 
> electrolytic caps" comes up so
> often in vintage electronics.  At small signal levels a lot of folk 
> don't care that the polarity
> could be reversed...

There is nothing philosophical about this, its electrochemistry.

<quote> Since the cathode's voltage capability is usually only about one 
volt, the electrolytic capacitor unit is limited in its steady-state 
reverse voltage capability to about one  volt. It has been found that in 
some cases transient reverse voltages in excess of 100 volts may appear 
on the capacitor for durations of around one  millisecond with no 
detrimental effects for thousands of cycles; however it is not clear 
what the actual cathode potential is in these cases. What is known is 
that extended reverse voltage for time intervals as short as one second 
can cause significant heating of the  electrolyte and of the anode 
oxide. </quote>

From: http://electrochem.cwru.edu/ed/encycl/art-c04-electr-cap.htm

Cheers,
  René

-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159