14 Feb
2010
14 Feb
'10
12:27 p.m.
On Feb 14, 2010, at 3:01 PM, Jochen Kunz wrote:
It's not an urban legend, unfortunately:
http://www.neurotica.com/misc/chinese_capacitor.jpg
I didn't take that picture, but I've seen it with my own eyes.
Other crap that happened was the fun of 2003 when capacitor
manufacturers starting making electrolytic capacitors using stolen
electrolyte formula that was incomplete.
X7R is an EIA-198 specification that defines electrical and
thermal behaviors of ceramic capacitors, not a type of dielectric
material. The first of the three-character code is a code letter
indicating lower limit of the operating temperature range, the middle
character is a code number indicating the upper limit of the
operating temperature range, and the third is a code letter
indicating the maximum change in capacitance allowed over that
operating temperature range.
-Dave
--
Dave McGuire
Port Charlotte, FL
There was some
criminal stuff going on with electrolytes in this era,
AFAIK this is an urban legend. And that legend was about aluminium
electrolyte capacitors, not tantalum. 
There was one
chemical manufacturer pinpointed,
that was supplying XR7 or whatever electrolyte to all the
manufacturers.
X7R is a ceramic dielectric. It has nothing to do with electrolyte
capacitors. Even cheap X7R capacitors are far more reliable then
electrolyte capacitors.