Hi If we ever go back to tubes we're going to have a bunch of tech's knocked out on the floor. Nobody has a clue about high voltage any more. You had to have a good respect for it on a tube circuit or you got in big trouble.
Bob On Jan 27, 2010, at 9:23 PM, Steve Rooke wrote: > Wasn't life so much easier with valves (tubes)... > > :-) > > Steve > > 2010/1/27 Bob Camp <[email protected]>: >> Hi >> >> If you are manually loading up a wire bonder with conventional CMOS chips, >> ESD damage is a very real thing. You can haul the chip over to a SEM and >> actually take pictures of he craters you blast in it. Very cool pictures. No >> cat's, carpets, or Windhurst machines needed. Just normal operators with >> missing wrist straps will do the trick quite nicely. >> >> Bob >> >> >> On Jan 26, 2010, at 2:21 AM, [email protected] wrote: >> >>> Back about 1981, we had piles of 6502s, etc and decide to some "antistatic >>> testing". We put a 40pin ZIF socket into a VIC-20, and then set about >>> trying to fry the uP using carpet, a cat, car seats, etc. The DUT was then >>> put back into the VIC and series of tests run to verify operation. I don't >>> think we ever had a failure. Of course, there may have been some hiding >>> that we missed, but all the static damage I've seen has been pretty severe. >>> >>> That said, I always use a wrist strap and mat if I'm working on something I >>> don't want to break further. >>> >>> -Dave >>> ----- Original Message ----- >>> From: "Charles P. Steinmetz" <[email protected]> >>> To: "Discussion of precise time and frequency measurement" >>> <[email protected]> >>> Sent: Monday, January 25, 2010 11:27:11 AM GMT -07:00 US/Canada Mountain >>> Subject: Re: [time-nuts] Conducting Bench Top Material >>> >>> Bruce wrote: >>> >>>> Although over the years the non-conductive top has been an asset in >>>> avoiding short circuits, etc., I am concerned about static discharges when >>>> handling modern semiconductors. Would it make sense to spray the Masonite >>>> with a weak copper sulphate or similar solution so as to make the masonite >>>> slightly conductive, but not so conductive that 155 VAC connections >>>> could not >>>> safely rest upon it? Is there a better-suited material that could be used >>>> to replace the Masonite? >>> >>> I notice that many folks who have contributed on this thread use >>> anti-static benchtops, but I have never found it necessary (and I try >>> to keep the RH in my house under 45% -- it is generally 20% or less >>> in the winter). I've been fooling with static-sensitive parts for 35 >>> years and haven't lost one to static yet. With that perspective, my >>> preferred benchtop is white Formica with a very, very slightly >>> pebbled surface. Very durable, including to molten solder, and small >>> parts show up well. I use rubberized "gunsmith" mats for preventing >>> scratches to delicate workpieces (these happen to be anti-static, but >>> that is not why I have them). >>> >>> Other bench thoughts: >>> >>> Bench depth is very important. I sometimes work on equipment that is >>> more than 24" deep, so I want at least 30" of clear space in front of >>> any obstructions (power strips, Variac, test equipment, >>> whatever). In the past, I used a "flying bridge" over the rear 18" >>> of a 48"-deep bench to elevate the test equipment, which worked very >>> well. Now I use 24" deep adjustable wire-rack shelving units behind >>> a 30" benchtop (As others have pointed out, you can do the same with >>> equipment racks -- I'm not a fan of rack-mounting test equipment >>> unless the racks are anchored and everything is on slides, which I >>> was not prepared to do). I don't have enough shop real estate to >>> have a permanent access aisle behind the test equipment, so the bench >>> and racks have large (5") locking polyurethane wheels and can be >>> pulled out relatively easily for reconfiguration. This provides >>> plenty of stability for electronic projects, but you wouldn't want to >>> mount a big vise on the bench and try to bend 1" rebar. For that, I >>> have a separate metalworking shop. >>> >>> Bench height is also important. I prefer a tall bench, suited to >>> working standing or sitting on an ergonomic stool, so my bench top is >>> 44" above the floor -- a bit below my standing elbow height. >>> >>> Finally, one can never have too many power outlets, or too much >>> light, in a workshop. Lighting should be arranged so that it doesn't >>> cause specular reflections from the workpiece or the faces of test >>> equipment. >>> >>> Best regards, >>> >>> Charles >>> >>> >>> >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > > > > -- > Steve Rooke - ZL3TUV & G8KVD > A man with one clock knows what time it is; > A man with two clocks is never quite sure. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
