Bad resistors
in [Design]
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From: DrParnassus on 22 Jun 2010 19:54 On Tue, 22 Jun 2010 21:51:47 GMT, 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. > >New to me :-) A normal handheld DVM barely measures 1MOhm correctly so anything up there and over will not likely be easily measured with cheap handhelds.
From: DrParnassus on 22 Jun 2010 19:55 On Tue, 22 Jun 2010 21:58:52 +0000 (UTC), Cydrome Leader <presence(a)panix.com> wrote: >what's the color code for M again? Wow, you really are a fresh out of or still in school know nothing dweeb.
From: Richard Henry on 22 Jun 2010 20:08 On Jun 22, 4:54 pm, DrParnassus <DrParnas...(a)hereforlongtime.org> wrote: > On Tue, 22 Jun 2010 21:51:47 GMT, Jan Panteltje > > <pNaonStpealm...(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 fromwww.voti.nl, so beware. > >All are marked with the right color code for 2M7. > > >New to me :-) > > A normal handheld DVM barely measures 1MOhm correctly so anything up > there and over will not likely be easily measured with cheap handhelds. Apparently some read correctly.
From: John Larkin on 22 Jun 2010 20:59 On Tue, 22 Jun 2010 16:54:15 -0700, DrParnassus <DrParnassus(a)hereforlongtime.org> wrote: >On Tue, 22 Jun 2010 21:51:47 GMT, 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. >> >>New to me :-) > > A normal handheld DVM barely measures 1MOhm correctly so anything up >there and over will not likely be easily measured with cheap handhelds. AlwaysWrong! AlwaysWrong! AlwaysWrong! 1.1 meg and 4.7 meg, 5% resistors read... Fluke 8845A benchtop 1.08220 M 4.6390 M Fluke 87 handheld 1.083 M 4.64 M Fluke 75 handheld 1.084 M 4.66 M The last two haven't been calibrated in years. The biggest problem is the terrible TC of the carbon film resistors. I'll try a cheap Extech when I get home. AlwaysWrong! AlwaysWrong! AlwaysWrong! John
From: Jay Ts on 22 Jun 2010 21:11
Jan Panteltje 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. > > New to me :-) I will assume you have a decent meter and know how to use it. The web store looks like a tiny business, and you seem to be complaining that you bought electronic components from a guy who explained on his site that he is a software engineer, and now you are not happy with your results. Before posting bad words about him publicly, he deserves to hear from you and have an opportunity to correct the problem. Try to resolve the problem first, before posting to the world. Aside from that, I've heard many stories of reject electronic parts being resold by unethical businesses. Because of that, I always buy parts from large, well-known companies (e.g., Mouser and Digi-Key in the USA). Even they are not absolutely 100% perfect. Jay Ts |