> What are you doing us so late? I am going to bed now... Sorry 'bout the late hour guy! ... Then there is the *true* story* of the tech in "Equipment R&M" (Equip Repair and Maintenance, renamed by us to 'Equipment R*pe and Maim' as they would sometimes muck-up otherwise fine HP and Tek lab gear in contrast to their charter which was to 'cal' (calibrate) and repair said gear) who killed himself through the absolute negligent misuse of a High Voltage TV probe - TV HV probes are designed to measure POSITIVE HV potentials in excess of +20 KV. This style had a built-in (integral) meter, a 'ground' clip normally attached to the chassis and a large insulted 'prod' (probe tip) that is shoved under the red cap on a CRT to 'measure' the high voltage potential that accelerates electrons onward toward the CRT screen. The ingenuious R&M tech in this instance however needed to measure a high NEGATIVE voltage (probably another TWT power supply) and connected up the TV HV probe with the GROUND clip to the ckt under test (the NEGATIVE HV probe lead) and the probe tip to ground (the POSITIVE HV probe lead). He proceeded to firmly grip the handle (no doubt thinking this was INSULATED suffiently - it wasn't, and turned out to be his untimely undoing) and turned on the apparatus ... After that incident those style probes were banned. Jim ----- Original Message ----- From: "Giles Honeycutt" To: Sent: Wednesday, February 13, 2002 11:11 PM Subject: Re: [EE]: bad oscilloscope? > Jim, > I would say he had many other problems also. Perhaps he could get a voltage > doubler and start a jacob's ladder using his body and the scope as the > ladder?? > By the way, a good example of high voltage stupidity: > > http://www.drmegavolt.com/underpages/warning.asp > or got to www.drmegavolt.com for his main page. > > What are you doing us so late? I am going to bed now... > > Best regards, > Giles > > > >From: Jim > >Reply-To: pic microcontroller discussion list > >To: PICLIST@MITVMA.MIT.EDU > >Subject: Re: [PICLIST] [EE]: bad oscilloscope? > >Date: Wed, 13 Feb 2002 22:41:19 -0600 > > > > "> Just convert the 3 pin wall plug to a 2 pin > > >wall plug. (lift the ground pin)" > > > >We had a young tech who did this to measure > >the grid drive to a small TWT (traveling wave > >tube) one day (p/o the GM (Ground Mappping) RADAR > >in a Panavia Tornado Nose RADAR) - the only problem > >was the drive was WRT (with respect to) the cathode > >of the TWT - and the cathode sat around -3000 VDC ... > >the Tek 475 *did* stand off this voltage (the spec > >states something like 500 V or so) ... > > > >Normally a special isolation transformer and > >insulated 'cage' for the scope was used - someone > >had not informed this young man as part of his > >training however. > > > >Jim > > > > > > > >----- Original Message ----- > >From: "Giles Honeycutt" > >To: > >Sent: Wednesday, February 13, 2002 10:26 PM > >Subject: Re: [EE]: bad oscilloscope? > > > > > > > Rodrigo, > > > Just convert the 3 pin wall plug to a 2 pin wall plug. (lift the ground > > > pin) > > > > > > > > > > > > Best regards, > > > Giles > > > > > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body