Bad resistors
in [Design]
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From: Robert Baer on 23 Jun 2010 22:06 DrParnassus wrote: > On Tue, 22 Jun 2010 21:50:58 -0700, Robert Baer <robertbaer(a)localnet.com> > wrote: > >> I bet the Extech will correlate rather well with the Flukes; i have >> one and it reads within 0.2% worst case for all (valid) values except >> when the value is less than a few hundred ohms where contact resistance >> becomes part of the reading. > > Now try a battery of parts that are all between 2 Mohm and 20 Mohm. > > I'll bet your claim falls apart at that point. > > You cannot move the goal posts, twit. Did not "move" anything, dufus; read: all (valid) values.
From: DrParnassus on 23 Jun 2010 23:58 On Wed, 23 Jun 2010 18:15:17 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Wed, 23 Jun 2010 11:01:06 -0700, DrParnassus ><DrParnassus(a)hereforlongtime.org> wrote: > >>On Wed, 23 Jun 2010 10:12:47 -0700, John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>>On Wed, 23 Jun 2010 09:28:26 -0700, DrParnassus >>><DrParnassus(a)hereforlongtime.org> wrote: >>> >>>>On Wed, 23 Jun 2010 08:50:37 -0700, John Larkin >>>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>>>>Dale says they're expensive because hardly anybody buys them. >>>> >>>> >>>> If they have to do a lot run simply because one order triggered it, >>>>they lose money if it isn't a pretty big order, and SMD has expiration >>>>dates due to termination oxidation issues so they cannot simply store the >>>>over-production stock either. Though I will take old parts because they >>>>are usable for proto builds. >>> >>>As I said, they are axial RC07 types, not SMD. >>> >>>They do stock 22M, available from distributors at a more sensible >>>price, and 33M, also distributor stock maybe. The 50M ones are >>>apparently not much in demand. >>> >>>All *are* 1% parts. And we can measure them accurately. >>> >>>I need a small constant current, and it's a battle between Johnson >>>noise current and shot/excess noise. It's not easy to generate a nA >>>level quiet constant current. The alternative was ten 10M >>>surface-mount thinfilms in series, which we don't have room for. >>> >>>John >>> >> You left out one over f. > >Do you even know what 1/f noise is? > >John No, john. I characterized JV circuits for years. We never came across it. Come back when you are not being an absolute insult to the entire industry, John.
From: Greegor on 24 Jun 2010 00:00 Archie > Sorry, John. Where I come from accuracy matters, Such demanding psychiatric hospitals.
From: DrParnassus on 24 Jun 2010 01:00
On Wed, 23 Jun 2010 21:57:59 -0700 (PDT), Greegor <greegor47(a)gmail.com> wrote: > >I'm trying to imagine We've noticed. Do it somewhere else, fuckhead. |