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From: Spehro Pefhany on 15 May 2010 20:38 On Fri, 14 May 2010 06:38:33 -0700, the renowned John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Fri, 14 May 2010 08:48:58 -0400, "Oppie" <Oppie(a)saynotospam.com> >wrote: > >>"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message >>news:t38ou5lhrikpleklddpca6b255nhbt67ui(a)4ax.com... >>> >>> Yes, lots of rusty VWs on his lawn and on the street. >>> >> >>Got an address so we can check it out on Google Earth? > >I don't think I should do that. His habit of collecting rusty VWs is >something he's written about in his columns, so that's already public. >His address, and anything I know about him locally, is a private >matter. > >John Not hard to find though: http://www.speff.com/BP.jpg Do you think that 2nd story thing is original 1918? Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff(a)interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
From: Michael A. Terrell on 27 May 2010 14:38 John Larkin wrote: > > On Thu, 13 May 2010 09:23:56 -0700, "Joel Koltner" > <zapwireDASHgroups(a)yahoo.com> wrote: > > >"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message > >news:6r5ou5lcgjqv2cg8vbg1831506uqtmod4g(a)4ax.com... > >> Such brilliance! How do they keep doing it? > > > >A lot of graduating BSEEs today never really got that whole thing about > >superposition, I suspect? :-) > > > >Hmm... there might be a good interview question in there somewhere... "It's > >clear you can use an op-amp to sum an arbitrary number of inputs -- both with > >positive and negative gains -- but why is it that the vast majority of the > >time in an 'application example' you see people suggest only the inverting > >form?" > > > >Although I think it was Jim or someone who mentioned that these days some > >people don't even get past, "What's the approximate Vbe of any unremarkable > >transistor at reasonable currents?" :-) > > I like this as a test: > > +10V > | > | > | > | > c > +5V--------------b > e > | > | > 1K > | > | > | > | > gnd > > What's the base voltage? > > What's the base current? > > What's the emitter voltage? > > What's the collector current? > > What's the collector voltage? What type of transistor? NPN or PNP? > Any other comments? > > I'm not kidding. One "experienced ee" said that, since the transistor > is saturated, the collector voltage is zero. A tech applicant said > that the base voltage is 0.6. > > Some people got it right, but nobody has mentioned oscillation so far. > > John -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
From: John Larkin on 27 May 2010 21:36 On Thu, 27 May 2010 14:38:24 -0400, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wrote: > >John Larkin wrote: >> >> On Thu, 13 May 2010 09:23:56 -0700, "Joel Koltner" >> <zapwireDASHgroups(a)yahoo.com> wrote: >> >> >"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message >> >news:6r5ou5lcgjqv2cg8vbg1831506uqtmod4g(a)4ax.com... >> >> Such brilliance! How do they keep doing it? >> > >> >A lot of graduating BSEEs today never really got that whole thing about >> >superposition, I suspect? :-) >> > >> >Hmm... there might be a good interview question in there somewhere... "It's >> >clear you can use an op-amp to sum an arbitrary number of inputs -- both with >> >positive and negative gains -- but why is it that the vast majority of the >> >time in an 'application example' you see people suggest only the inverting >> >form?" >> > >> >Although I think it was Jim or someone who mentioned that these days some >> >people don't even get past, "What's the approximate Vbe of any unremarkable >> >transistor at reasonable currents?" :-) >> >> I like this as a test: >> >> +10V >> | >> | >> | >> | >> c >> +5V--------------b >> e >> | >> | >> 1K >> | >> | >> | >> | >> gnd >> >> What's the base voltage? >> >> What's the base current? >> >> What's the emitter voltage? >> >> What's the collector current? >> >> What's the collector voltage? > > > What type of transistor? NPN or PNP? Thank you for coming by to interview. Best of luck. John
From: Michael A. Terrell on 28 May 2010 01:54 John Larkin wrote: > > On Thu, 27 May 2010 14:38:24 -0400, "Michael A. Terrell" > <mike.terrell(a)earthlink.net> wrote: > > > > >John Larkin wrote: > >> > >> On Thu, 13 May 2010 09:23:56 -0700, "Joel Koltner" > >> <zapwireDASHgroups(a)yahoo.com> wrote: > >> > >> >"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message > >> >news:6r5ou5lcgjqv2cg8vbg1831506uqtmod4g(a)4ax.com... > >> >> Such brilliance! How do they keep doing it? > >> > > >> >A lot of graduating BSEEs today never really got that whole thing about > >> >superposition, I suspect? :-) > >> > > >> >Hmm... there might be a good interview question in there somewhere... "It's > >> >clear you can use an op-amp to sum an arbitrary number of inputs -- both with > >> >positive and negative gains -- but why is it that the vast majority of the > >> >time in an 'application example' you see people suggest only the inverting > >> >form?" > >> > > >> >Although I think it was Jim or someone who mentioned that these days some > >> >people don't even get past, "What's the approximate Vbe of any unremarkable > >> >transistor at reasonable currents?" :-) > >> > >> I like this as a test: > >> > >> +10V > >> | > >> | > >> | > >> | > >> c > >> +5V--------------b > >> e > >> | > >> | > >> 1K > >> | > >> | > >> | > >> | > >> gnd > >> > >> What's the base voltage? > >> > >> What's the base current? > >> > >> What's the emitter voltage? > >> > >> What's the collector current? > >> > >> What's the collector voltage? > > > > > > What type of transistor? NPN or PNP? > > Thank you for coming by to interview. Best of luck. You're welcome. I would never want to work for you anyway. You could use either, even though one wouldn't work properly. It would either cause a shorted or open junction, but would give the voltages you indicated. Typical of a poorly thought out attempt to show 'superiority'. Your little 'test' reeks of ego and does nothing to find real workers. The ones who will find every problem, and why a design doesn't work. It reminds me of the employment test at Cincinnati Electronics. It had a dozen or so symbols you had to identify in one section. One of them was an N channel FET with a dot inside the circle. It looked like they started with the symbol for a gas regulator tube and added the extra lines to make a N channel FET. They threw a hissy fit when people told them it wasn't a valid symbol, yet they couldn't identify what it was. This was in the mid '70s. It was a running joke about the head of the department who created the stupid test. He didn't want people who thought, he wanted drones. -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
From: John Larkin on 28 May 2010 09:57
On Fri, 28 May 2010 01:54:15 -0400, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wrote: > >John Larkin wrote: >> >> On Thu, 27 May 2010 14:38:24 -0400, "Michael A. Terrell" >> <mike.terrell(a)earthlink.net> wrote: >> >> > >> >John Larkin wrote: >> >> >> >> On Thu, 13 May 2010 09:23:56 -0700, "Joel Koltner" >> >> <zapwireDASHgroups(a)yahoo.com> wrote: >> >> >> >> >"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message >> >> >news:6r5ou5lcgjqv2cg8vbg1831506uqtmod4g(a)4ax.com... >> >> >> Such brilliance! How do they keep doing it? >> >> > >> >> >A lot of graduating BSEEs today never really got that whole thing about >> >> >superposition, I suspect? :-) >> >> > >> >> >Hmm... there might be a good interview question in there somewhere... "It's >> >> >clear you can use an op-amp to sum an arbitrary number of inputs -- both with >> >> >positive and negative gains -- but why is it that the vast majority of the >> >> >time in an 'application example' you see people suggest only the inverting >> >> >form?" >> >> > >> >> >Although I think it was Jim or someone who mentioned that these days some >> >> >people don't even get past, "What's the approximate Vbe of any unremarkable >> >> >transistor at reasonable currents?" :-) >> >> >> >> I like this as a test: >> >> >> >> +10V >> >> | >> >> | >> >> | >> >> | >> >> c >> >> +5V--------------b >> >> e >> >> | >> >> | >> >> 1K >> >> | >> >> | >> >> | >> >> | >> >> gnd >> >> >> >> What's the base voltage? >> >> >> >> What's the base current? >> >> >> >> What's the emitter voltage? >> >> >> >> What's the collector current? >> >> >> >> What's the collector voltage? >> > >> > >> > What type of transistor? NPN or PNP? >> >> Thank you for coming by to interview. Best of luck. > > > You're welcome. I would never want to work for you anyway. > > You could use either, even though one wouldn't work properly. It >would either cause a shorted or open junction, but would give the >voltages you indicated. Typical of a poorly thought out attempt to show >'superiority'. > > Your little 'test' reeks of ego and does nothing to find real >workers. The ones who will find every problem, and why a design doesn't >work. That little "test" is performed in scribble/discussion mode, not as some formal sit-down thing. I don't want to hire a test tech or an engineer who doesn't understand how a transistor works. Or in this case, what a voltmeter does. This question is *not* designed to be tricky; it's a bog simple emitter follower, which a shocking number of "engineers" don't seem to understand. They say stuff like "well, it's been a while since..." Of course, when I draw this I use a real transistor symbol, not ascii art. Last EE I hired, I flew him in and spent a full day designing an actual product with him... no test, no interview. > > > It reminds me of the employment test at Cincinnati Electronics. It >had a dozen or so symbols you had to identify in one section. One of >them was an N channel FET with a dot inside the circle. It looked like >they started with the symbol for a gas regulator tube and added the >extra lines to make a N channel FET. Those tricky tests are pretty lame. A few real, simple circuits will tell me what I need to know. The best way to hire is to first work with someone part-time, as a consultant or intern, rather than interview/test, which isn't very predictive of reality. John |