Bad resistors
in [Design]
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From: DrParnassus on 23 Jun 2010 13:51 On Wed, 23 Jun 2010 09:26:14 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >Read the Agilent and Keithley specs and then you can start weaseling >about the dictionary definition of "accurately." You do not understand. I am not talking about the equipment.
From: Nico Coesel on 23 Jun 2010 13:47 Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote: >On a sunny day (Tue, 22 Jun 2010 22:09:48 GMT) it happened nico(a)puntnl.niks >(Nico Coesel) wrote in <4c21346d.364231437(a)news.planet.nl>: > >>Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote: >> >>>Got 10 resistors on tape marked 2M7. >>>Used one, circuit did not work right. >>>Took some testing ... before I measured the resistors. >>>Of the 10 several are 620 k and not 2M7. >>>Bought from www.voti.nl, so beware. >>>All are marked with the right color code for 2M7. >> >>Sure you didn't hold the resistors while measuring? > >LOL, no I know about that one :-) Just checking :-) >I was so suprized I measured them 3 times, and then again a little later. Did you contact the guy from Voti? I don't know him but from what I've heard he is not into selling junk. -- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... nico(a)nctdevpuntnl (punt=.) --------------------------------------------------------------
From: DrParnassus on 23 Jun 2010 13:53 On Wed, 23 Jun 2010 09:30:07 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Wed, 23 Jun 2010 08:37:52 -0700, DrParnassus ><DrParnassus(a)hereforlongtime.org> wrote: > >>On Wed, 23 Jun 2010 07:05:09 -0700, John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>>Extech makes nice stuff. I think FLIR bought them to keep them from >>>introducing a competitive IR imager. >>> >>>John >> >> Total bullshit. >> >> Extexh did not nor does not have the expertise to make an IR imager. >> >> I worked for an IR instrument maker, and FLIR buys calibration >>equipment from them, and never felt threatened by our IR imager, which >>has been around since before extech even existed. >> >> Raytheon or Square-D is a bigger threat in that market, and I am sure >>that FLIR has no worries about them either. FLIR has a main market niche >>that nobody encroaches on. >> >> Extech was NEVER a player in IR and especially not ANY military IR, and >>any gear they did carry, they bought elsewhere and put their name on it. >> >> You're a goddamned idiot, as usual. > >http://www.extechstore.com/extech-irc40.aspx > >One day in the not-so-far future you'll be able to buy thermal imagers >at Home Depot for under $250, eventually under $100. > >John I would bet you the value of your entire firm that what they put their name on was an OEM device with their skin thrown on. Guaranteed. Wanna bet?
From: DrParnassus on 23 Jun 2010 13:59 On Wed, 23 Jun 2010 10:02:51 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Tue, 22 Jun 2010 23:21:52 -0700, DrParnassus ><DrParnassus(a)hereforlongtime.org> wrote: > >>On Tue, 22 Jun 2010 20:04:34 -0700, John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>> >>>Fingerprints are no problem at 1 Gohm (that's a thousand megohms to >>>you.) Well, depending on what's on your fingers. >> >> You're an idiot. > >No, I just wash my hands more often than you do. > >I deliberately fingerprinted a Pomona dual banana plug that had a 1G >resistor attached. I couldn't see the measured resistance change. > >Try it. > >John The fingerprints go on the resistor, not the banana plug. And a 1G device as the dropping resistor for the feedback for an HV circuit will read fine on a meter, but in use, it will fail if it has those prints, or 'coffee breath' or other VOC across it. What the meter reads may be fine for an LV application, but that 'dirt' is where part of your noise is coming from, and in HV, it makes for inaccuracy, and complete failure modes. Failure, especially once in the hands of the customer in a potted product, is not an option.
From: DrParnassus on 23 Jun 2010 13:59
On Wed, 23 Jun 2010 17:08:07 GMT, Jan Panteltje <pNaonStpealmtje(a)yahoo.com> wrote: >Even a first year student would not be so arrogant as you. You're an idiot. |