my lab
in [Design]
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From: John Larkin on 19 Oct 2009 16:02 On Sat, 17 Oct 2009 21:03:41 -0700, "JosephKK"<quiettechblue(a)yahoo.com> wrote: >On Sat, 17 Oct 2009 09:25:35 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Sat, 17 Oct 2009 08:53:38 -0700, >>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >> >>>On Fri, 16 Oct 2009 09:29:42 -0700, John Larkin >>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>>On Thu, 15 Oct 2009 21:19:08 -0700, >>>>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >>>> >>>>>On Sun, 11 Oct 2009 14:09:40 -0700, Joerg <invalid(a)invalid.invalid> >>>>>wrote: >>>>> >>>>>>John Larkin wrote: >>>>>>> On Sat, 10 Oct 2009 14:40:18 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>> wrote: >>>>>>> >>>>>>>> John Larkin wrote: >>>>>>>>> On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs >>>>>>>>> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >>>>>>>>> >>>>>>>>>> John Larkin wrote: >>>>>>>> [...] >>>>>>>> >>>>>>>>>>> Longterm, gigabit (and whatever comes next) Ethernet is the only >>>>>>>>>>> reasonable instrument bus. >>>>>>>>>>> >>>>>>>>>>> John >>>>>>>>>>> >>>>>>>>>> Sure, unless you need timing coherence between instruments. >>>>>>>>> The IEEE-1588 protocol can sync boxes to within nanoseconds over >>>>>>>>> ethernet >>>>>>>>> >>>>>>>>> http://en.wikipedia.org/wiki/Precision_Time_Protocol >>>>>>>>> >>>>>>>>> >>>>>>>>>> Also there's all this nice stuff around that's GPIB & RS232. >>>>>>>>> It's also nice when an instrument has a web-page interface, and can be >>>>>>>>> telnet-ed to, without any PC plugin boards or drivers. Or distance >>>>>>>>> limits. >>>>>>>>> >>>>>>>> Hey, then you could sit there at Zeitgeist all day long and run it all >>>>>>>> via a 3G phone :-) >>>>>>>> >>>>>>> >>>>>>> I guess future instruments will be Twitter compatible. >>>>>>> >>>>>> >>>>>>Yeah, even IEEE fell for that. An engineer's organization, of all >>>>>>places. Pathetic. >>>>> >>>>>And since when are engineers not people with all their follies? >>>> >>>>Good engineers discipline their follies with reason, so that the >>>>things they design work. >>>> >>>>John >>> >>>Like MS Vista works? Like many MS compatible products? Like the >>>Tacoma narrows bridge? Please study up on engineering failures, it >>>might help you gain humility. >> >>Vista isn't engineering. There's no math, no theory, no science in >>writing C++ GUIs. Read "Showstopper!" and then read some Windows >>source code. >> >>I have a pretty good collection of books about engineering failures >>(mostly civil and software stuff), company failures, scientific fraud, >>and engineering philosophy. >> >>Just a few in reach on the shelf... >> >>The Hubbel Wars >> >>Plastic Fantastic >> >>Engineering in History >> >>Why Things Fall Down >> >>Why Things Don't Fall Down >> >>The Undergrowth of Science >> >>Why Things Bite Back >> >>Fatal Defect: Chasing Killer Computer Bugs >> >>Showstopper! >> >>The World's Worst Aircraft >> >>The Truth About Chernobyl >> >>F'd Companies >> >>The Moth in the Machine >> >>and a bunch more, probably upstairs. >> >> >>Read any of these? Any suggestions for others? >> >>But humility? Our stuff usually works first time, without prototypes, >>because we doubt everything and triple-check everything. >> >>John >> > >Parts of a few, thanks for the list, it goes into my shopping list. "The Hubble Wars" is especially good. The arrogant mirror grinders decided their mirror was so good that only one test fixture was good enough to check it. Basic, routine crosschecks were scorned. A good amateur telescope maker could have detected the figure error. It never made an image before it was launched into orbit. When the telescope wouldn't focus and a meeting was called to find out why, and the real problem began to emerge, one of the optics designers stepped out into the hallway and vomited. John
From: Abdul on 20 Oct 2009 03:22 On Oct 19, 2:54 am, JW <n...(a)dev.null> wrote: > On Wed, 14 Oct 2009 08:44:46 -0700 Joerg <inva...(a)invalid.invalid> wrote > in Message id: <7jm9viF3575h...(a)mid.individual.net>: > > > > >JW wrote: > >> On Mon, 12 Oct 2009 15:10:57 -0700 Joerg <inva...(a)invalid.invalid> wrote > >> in Message id: <7jhnrlF351k3...(a)mid.individual.net>: > > >>> JW wrote: > >>>> On Fri, 09 Oct 2009 17:09:54 -0700 Joerg <inva...(a)invalid.invalid> wrote > >>>> in Message id: <7ja1mpF2pe4k...(a)mid.individual.net>: > > >>>>> If you have to use equipment at clients a lot and its legacy HP stuff > >>>>> the USB version is very practical. Plug it in, hit print on the > >>>>> analyzer, done. But Abdul (thePrologixdesigner) and I had to iron out > >>>>> a bias problem before it liked HP legacy gear. > >>>> I've been having problems communicating with HP 60XX power supplies > >>>> (6034 and 6038 come to mind) Do you have any details on the fix you might > >>>> share? > > >>> What kind of problem? If you have an olderPrologixdo a firmware > >>> upgrade. The designer (Abdul) and I have found out that the logic > >>> threshold on thePrologixis way too high. After some discussion it > >>> turned out that pull-up resistors could be engaged inside the uC in the > >>>Prologix. Not a perfect solution but that made it work with the HP3577.. > >>> So Abdul changed the firmware and made that available. > > >> I'm not exactly sure what the problem is, but any queries to the power > >> supply will return garbage. Using John Miles'Prologix.exeGPIB > >> configuration utility > >>http://www.thegleam.com/ke5fx/gpib/readme.htm#prologix > >> When I do a simple ID?, the 6034A supply floods the program with what > >> appears to be the <CR> character. The program will not accept any more > >> commands and the windows hourglass is seen when the mouse is hovered over > >> the Proligix.exe program. I have to shut off the power supply to get the > >> program back under control. I did do a firmware update about 6 months ago, > >> but I see there's been at least one update since then. I'll update the > >> firmware again and see what happens. > > >I think it's about that long ago that he fixed the firmware, but check. > > >That doesn't sound like aPrologixproblem at all. Try to talk to the > >power supply using Hyperterminal. AGPIB-equipped box should not respond > >with a barrage of nonsensical data. What happened with mine was that the > >responses were ok but one bit was stuck. So I always got a time-limited > >set of data but when deciphering it the information in the data sounded > >like Swahili. > > >Sending was never a problem, receiving was because thePrologix > >threshold sits around 3V and that's way too high for old bipolar TTL. > >And that's what most vintage gear will have inside. > > I updated the firmware this weekend and tried using Tera Term Pro to > communicate with the HP 6034A. Got the same result - floods the terminal > emulator with what appears to be <CR> or linefeeds. Weird. Try the following using TeraTerm Pro ++mode 1 ++addr <GPIB address of HP6034A> ++auto 0 ID? ++read eoi Does this command sequence work better? Abdul (Prologix)
From: JosephKK on 21 Oct 2009 01:28 On Mon, 19 Oct 2009 13:02:28 -0700, John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >On Sat, 17 Oct 2009 21:03:41 -0700, >"JosephKK"<quiettechblue(a)yahoo.com> wrote: > >>On Sat, 17 Oct 2009 09:25:35 -0700, John Larkin >><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>>On Sat, 17 Oct 2009 08:53:38 -0700, >>>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >>> >>>>On Fri, 16 Oct 2009 09:29:42 -0700, John Larkin >>>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>>>>On Thu, 15 Oct 2009 21:19:08 -0700, >>>>>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >>>>> >>>>>>On Sun, 11 Oct 2009 14:09:40 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>wrote: >>>>>> >>>>>>>John Larkin wrote: >>>>>>>> On Sat, 10 Oct 2009 14:40:18 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> John Larkin wrote: >>>>>>>>>> On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs >>>>>>>>>> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >>>>>>>>>> >>>>>>>>>>> John Larkin wrote: >>>>>>>>> [...] >>>>>>>>> >>>>>>>>>>>> Longterm, gigabit (and whatever comes next) Ethernet is the only >>>>>>>>>>>> reasonable instrument bus. >>>>>>>>>>>> >>>>>>>>>>>> John >>>>>>>>>>>> >>>>>>>>>>> Sure, unless you need timing coherence between instruments. >>>>>>>>>> The IEEE-1588 protocol can sync boxes to within nanoseconds over >>>>>>>>>> ethernet >>>>>>>>>> >>>>>>>>>> http://en.wikipedia.org/wiki/Precision_Time_Protocol >>>>>>>>>> >>>>>>>>>> >>>>>>>>>>> Also there's all this nice stuff around that's GPIB & RS232. >>>>>>>>>> It's also nice when an instrument has a web-page interface, and can be >>>>>>>>>> telnet-ed to, without any PC plugin boards or drivers. Or distance >>>>>>>>>> limits. >>>>>>>>>> >>>>>>>>> Hey, then you could sit there at Zeitgeist all day long and run it all >>>>>>>>> via a 3G phone :-) >>>>>>>>> >>>>>>>> >>>>>>>> I guess future instruments will be Twitter compatible. >>>>>>>> >>>>>>> >>>>>>>Yeah, even IEEE fell for that. An engineer's organization, of all >>>>>>>places. Pathetic. >>>>>> >>>>>>And since when are engineers not people with all their follies? >>>>> >>>>>Good engineers discipline their follies with reason, so that the >>>>>things they design work. >>>>> >>>>>John >>>> >>>>Like MS Vista works? Like many MS compatible products? Like the >>>>Tacoma narrows bridge? Please study up on engineering failures, it >>>>might help you gain humility. >>> >>>Vista isn't engineering. There's no math, no theory, no science in >>>writing C++ GUIs. Read "Showstopper!" and then read some Windows >>>source code. >>> >>>I have a pretty good collection of books about engineering failures >>>(mostly civil and software stuff), company failures, scientific fraud, >>>and engineering philosophy. >>> >>>Just a few in reach on the shelf... >>> >>>The Hubbel Wars >>> >>>Plastic Fantastic >>> >>>Engineering in History >>> >>>Why Things Fall Down >>> >>>Why Things Don't Fall Down >>> >>>The Undergrowth of Science >>> >>>Why Things Bite Back >>> >>>Fatal Defect: Chasing Killer Computer Bugs >>> >>>Showstopper! >>> >>>The World's Worst Aircraft >>> >>>The Truth About Chernobyl >>> >>>F'd Companies >>> >>>The Moth in the Machine >>> >>>and a bunch more, probably upstairs. >>> >>> >>>Read any of these? Any suggestions for others? >>> >>>But humility? Our stuff usually works first time, without prototypes, >>>because we doubt everything and triple-check everything. >>> >>>John >>> >> >>Parts of a few, thanks for the list, it goes into my shopping list. > >"The Hubble Wars" is especially good. The arrogant mirror grinders >decided their mirror was so good that only one test fixture was good >enough to check it. Basic, routine crosschecks were scorned. A good >amateur telescope maker could have detected the figure error. It never >made an image before it was launched into orbit. > >When the telescope wouldn't focus and a meeting was called to find out >why, and the real problem began to emerge, one of the optics designers >stepped out into the hallway and vomited. > >John Oh no. That is not the whole story. The original testing design had testing that provably would have detected/prevented the problem. That testing was eliminated by a Proxmire style cost cutter. Then another Proxmire style cheater detector tried to raise hell about the deleted testing and was suppressed. Word of mouth and legerdemain, but my dad never lied to me about these kinds of things. If you know how to look the ripples were detectable. The same ripples are still preserved in various Congressional records.
From: John Larkin on 21 Oct 2009 13:17 On Tue, 20 Oct 2009 22:28:50 -0700, "JosephKK"<quiettechblue(a)yahoo.com> wrote: >On Mon, 19 Oct 2009 13:02:28 -0700, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Sat, 17 Oct 2009 21:03:41 -0700, >>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >> >>>On Sat, 17 Oct 2009 09:25:35 -0700, John Larkin >>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>>On Sat, 17 Oct 2009 08:53:38 -0700, >>>>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >>>> >>>>>On Fri, 16 Oct 2009 09:29:42 -0700, John Larkin >>>>><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>> >>>>>>On Thu, 15 Oct 2009 21:19:08 -0700, >>>>>>"JosephKK"<quiettechblue(a)yahoo.com> wrote: >>>>>> >>>>>>>On Sun, 11 Oct 2009 14:09:40 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>wrote: >>>>>>> >>>>>>>>John Larkin wrote: >>>>>>>>> On Sat, 10 Oct 2009 14:40:18 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> John Larkin wrote: >>>>>>>>>>> On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs >>>>>>>>>>> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >>>>>>>>>>> >>>>>>>>>>>> John Larkin wrote: >>>>>>>>>> [...] >>>>>>>>>> >>>>>>>>>>>>> Longterm, gigabit (and whatever comes next) Ethernet is the only >>>>>>>>>>>>> reasonable instrument bus. >>>>>>>>>>>>> >>>>>>>>>>>>> John >>>>>>>>>>>>> >>>>>>>>>>>> Sure, unless you need timing coherence between instruments. >>>>>>>>>>> The IEEE-1588 protocol can sync boxes to within nanoseconds over >>>>>>>>>>> ethernet >>>>>>>>>>> >>>>>>>>>>> http://en.wikipedia.org/wiki/Precision_Time_Protocol >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>>> Also there's all this nice stuff around that's GPIB & RS232. >>>>>>>>>>> It's also nice when an instrument has a web-page interface, and can be >>>>>>>>>>> telnet-ed to, without any PC plugin boards or drivers. Or distance >>>>>>>>>>> limits. >>>>>>>>>>> >>>>>>>>>> Hey, then you could sit there at Zeitgeist all day long and run it all >>>>>>>>>> via a 3G phone :-) >>>>>>>>>> >>>>>>>>> >>>>>>>>> I guess future instruments will be Twitter compatible. >>>>>>>>> >>>>>>>> >>>>>>>>Yeah, even IEEE fell for that. An engineer's organization, of all >>>>>>>>places. Pathetic. >>>>>>> >>>>>>>And since when are engineers not people with all their follies? >>>>>> >>>>>>Good engineers discipline their follies with reason, so that the >>>>>>things they design work. >>>>>> >>>>>>John >>>>> >>>>>Like MS Vista works? Like many MS compatible products? Like the >>>>>Tacoma narrows bridge? Please study up on engineering failures, it >>>>>might help you gain humility. >>>> >>>>Vista isn't engineering. There's no math, no theory, no science in >>>>writing C++ GUIs. Read "Showstopper!" and then read some Windows >>>>source code. >>>> >>>>I have a pretty good collection of books about engineering failures >>>>(mostly civil and software stuff), company failures, scientific fraud, >>>>and engineering philosophy. >>>> >>>>Just a few in reach on the shelf... >>>> >>>>The Hubbel Wars >>>> >>>>Plastic Fantastic >>>> >>>>Engineering in History >>>> >>>>Why Things Fall Down >>>> >>>>Why Things Don't Fall Down >>>> >>>>The Undergrowth of Science >>>> >>>>Why Things Bite Back >>>> >>>>Fatal Defect: Chasing Killer Computer Bugs >>>> >>>>Showstopper! >>>> >>>>The World's Worst Aircraft >>>> >>>>The Truth About Chernobyl >>>> >>>>F'd Companies >>>> >>>>The Moth in the Machine >>>> >>>>and a bunch more, probably upstairs. >>>> >>>> >>>>Read any of these? Any suggestions for others? >>>> >>>>But humility? Our stuff usually works first time, without prototypes, >>>>because we doubt everything and triple-check everything. >>>> >>>>John >>>> >>> >>>Parts of a few, thanks for the list, it goes into my shopping list. >> >>"The Hubble Wars" is especially good. The arrogant mirror grinders >>decided their mirror was so good that only one test fixture was good >>enough to check it. Basic, routine crosschecks were scorned. A good >>amateur telescope maker could have detected the figure error. It never >>made an image before it was launched into orbit. >> >>When the telescope wouldn't focus and a meeting was called to find out >>why, and the real problem began to emerge, one of the optics designers >>stepped out into the hallway and vomited. >> >>John > >Oh no. That is not the whole story. Of course it's not the whole story. Read the book for more. John
From: Martin Brown on 22 Oct 2009 03:53
John Larkin wrote: > On Tue, 20 Oct 2009 22:28:50 -0700, > "JosephKK"<quiettechblue(a)yahoo.com> wrote: > >> On Mon, 19 Oct 2009 13:02:28 -0700, John Larkin >> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >> >>> On Sat, 17 Oct 2009 21:03:41 -0700, >>> "JosephKK"<quiettechblue(a)yahoo.com> wrote: >>> >>>> On Sat, 17 Oct 2009 09:25:35 -0700, John Larkin >>>> <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>> "The Hubble Wars" is especially good. The arrogant mirror grinders >>> decided their mirror was so good that only one test fixture was good >>> enough to check it. Basic, routine crosschecks were scorned. A good That isn't quite true. Some of the routine cross checks *were* done and with hindsight showed the fault but were dismissed at the time as systematic errors in the much cruder procedures. In part it was management failure under time and cost pressure rather than an engineering problem. The primary null tester design was the gold standard and would have worked if it had been assembled and used correctly. The other two null testers correctly showed the spherical abberation but were believed at the time to be in error. PE manufacturing cocked it up. At the time it was the smoothest manmade surface ever produced. The backup mirror by Kodak that didn't fly was perfect in figure but not as nicely polished. I think it is now in a Washington museum. >>> amateur telescope maker could have detected the figure error. It never >>> made an image before it was launched into orbit. That may sound bad to you but the additional support structures to do that even as a zenith transit instrument in the Earth's gravity would have needed a lot of extra investment when they were being told to cut costs so the project could actually go ahead. Chances are if they had tried to do it right from an engineering perspective the entire thing would have been cancelled for cost overrun. And no-one wanted that. It didn't help that because of the Shuttle explosion the HST spent so long on the ground after being built that ground based observations and newer CCD technology moved onto its turf very quickly. It was a real shock when the HST would not focus properly at first light. >>> >>> When the telescope wouldn't focus and a meeting was called to find out >>> why, and the real problem began to emerge, one of the optics designers >>> stepped out into the hallway and vomited. I am not surprised. They figured the main mirror very precisely to the wrong curve. Although since it was neither spherical nor parabolic the average amateur telescope maker would not have been able to test it reliably without a null corrector. The level of error was huge in optical terms relative to the complex curve that was needed. But you cannot judge those sorts of curves with a pinhole and a razor a la ATM. >>> >>> John >> Oh no. That is not the whole story. > > Of course it's not the whole story. Read the book for more. I suspect there is an element of truth to what JKK says, but I knew parts of the team that did the HST image deconvolution code and a holographic determination of the figure error. The methods were borrowed from big dish radio astronomy. AFAIR the fault was manufactured in by excessive reliance on the primary test jig and ignoring hints from other less accurate tests that something might be amiss. I have previously posted a link to the NASA engineering report on the HST optics last time JKK blamed Proxmire for the HST mirror fault. Regards, Martin Brown |