Apparently, so I'm told, 47uf capacitors make good .22 air rifle slugs. On 26 Feb 2018 13:02, "David C Brown" wrote: > Many years ago at [company name withheld] we had a batch of several > hundred faulty electolytics which had to be disposed of. We had great > fun making a mortar - a piece of copper tube with a wooden plug with a na= il > through it - and having a target shooting contest. > > I also remember having a batch of memory board assembled with all the > tantalum capacitors put in the wrong way round. They lasted several week= s > until one night I was awoken by andanguished night shift operator reporti= ng > that small puffs of smoke were being regularly ejected from the machine a= nd > should he shut it down. > > __________________________________________ > David C Brown > 43 Bings Road > Whaley Bridge > High Peak Phone: 01663 733236 > Derbyshire eMail: dcb.home@gmail.com > SK23 7ND web: www.bings-knowle.co.uk/dcb > > > > > *Sent from my etch-a-sketch* > > On 26 February 2018 at 12:40, wrote: > > > High school. Rat's nest of free space wiring. Neon bulbs, capacitors > > (relaxation ring oscillator). Powered by half bridge directly from AC > line > > (no transformer). Main supply cap probably 50uF @ 200V or so. Short > > circuit. > > Small rocket dragging 115VAC / 160VDC all around the workbench. Much > > excitement. > > > > - - Bob Ammerman > > RAm Systems > > > > -----Original Message----- > > From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behal= f > > Of > > DrSkip > > Sent: Monday, February 26, 2018 12:09 AM > > To: piclist@mit.edu > > Subject: Re: [EE] "X" marks the spot > > > > I suspect the X is initially weaker than the glue holding the can on, s= o > > rapid pressure increase will break open there. Perhaps over the 30 > minutes > > heat weakened the glue to the point of it being the weak point for a > > gradual > > pressure buildup. > > > > Dr Skip > > > > > > On 02/25/2018 08:36 PM, Bob Blick wrote: > > > By mistake I put an electrolytic capacitor in backwards. A very gener= ic > > 100uF, 50V cap exposed to 16V with the equivalent of about 700 ohms in > > series with it. It lasted about 30 minutes, then went off with a bang. > You > > can maybe see the damaged heatshrink where the can hit an immovable > object. > > > > > > Please note the scored cross on the top of the can. Isn't that > > > supposed to split and protect me from its rapid self-disassembly? Yes= , > > > I was right there, close at hand, trying to figure out why all the > > > voltages were wrong. Perhaps their die for the venting "X" was worn > > > out after 20 million caps. I guess that's what I get when I pay USD > > > 0.03 for caps off of Aliexpress instead of USD 0.11 at Digi-Key :) > > > > > > I guess I learned a lesson in false economy today. I didn't lose an > eye, > > but I'm going to change my buying habits a little. Obviously I made a > > mistake putting the cap in wrong, but if I'd used a quality cap perhaps > I'd > > have only been startled with a scary hiss instead of a projectile. Take > > heed! How many lives do you really have? > > > > > > Cheerful regards, > > > > > > Bob > > > > > > > > > > > > > > > > -- > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > View/change > > your membership options at http://mailman.mit.edu/ > mailman/listinfo/piclist > > > > -- > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .