PDP 11 gear finally moved

On Wed, 22 Jul 2015, Chuck Guzis wrote: I believe there are a few webpages out there written by people who have tried it. From what I remember reading about them years ago, they had no success when they tried to use them as replacements in switch mode power supplies (no surprise, since the solid polymer parts they attempted to use had way to low of ripple current rating for that application) but had better results with certain PC motherboards. I use solid polymers as replacements in some applications, and as they continue to decrease in cost, I've been considering using them more for replacement of aging SMD aluminum electrolytics. One application where I particularly like solid polymers is for replacement of the vcore regulator filter capacitors on Pentium 4 industrial single board computers (yes, the P4 is still /widely/ used and extremely common in that market, although it is slowly being replaced by the Core Duo). The original aluminum electrolytics in that application are usually 6.3V rated parts while the solid polymer replacements are 2.5V or 4V (vcore is under 2V). In addition to long term stability, another major benefit to solid polymers is that unlike aluminum electrolytics and solid tantalums, solid aluminum polymers they can be used at their full rated voltage with no ill effects. The only real downside that I know of for a solid polymer is that they have an incredibly low ESR (less than 0.01 ohm), which can actually upset older circuit designs which were not designed for capacitors with such a low ESR.