On Thursday, May 21, 2020 at 10:35:09 AM UTC-4, jla...@highlandsniptechnology.com wrote:> On Thu, 21 May 2020 01:55:31 -0700 (PDT), Michael Terrell Wrote: > > > >We were just starting to automate testing, but that was almost 19 years ago. Documentation and board or model number matched the blank board, plus the BOM and test procedure for different versions but with over 20 modules in a unit, plus a separate plug in tuner for older models (depending on which microwave band) still complicated issues. Add that the company had been around since 1968 which was before most small businesses used computers, the system was deeply embedded in the daily operations. They had changed their part numbering system, once and it was a nightmare. Every BOM had to be rewritten, on a typewriter, then all old copies destroyed. > > > > On top of that, when they decided to close their original Rockville Maryland plant, the employees shredded every document in the vault, plus all working copies, leaving the engineers the task of reverse engineering the last complete units and to recreate the mountain of data. > > Some companies have a "configuration control" department, whose job is > to control all the documents and their relationship, and make sure the > right stuff gets manufactured and remembered. All documents have to be > submitted to them. > > Makes sense; keeping this stuff organized is non-trivial, especially > when mistakes can kill people.We did a lot of work for NASA and NOAA. We supplied their 'Command Destruct Receivers. If one of those failed, a rocket could kill a lot of people.
why do they do this?
Started by ●May 18, 2020
Reply by ●May 21, 20202020-05-21
Reply by ●May 21, 20202020-05-21
On 19/05/2020 00:41, John Larkin wrote:> > ST makes a nice little LDO, super-low dropout with an aux Vbias > supply. Saves me from rolling my own with an opamp and a mosfet. > > It's an ST1L08. > > So why is the data sheet file en.DM00123507.pdf ? >What's wrong with the microchip part? 1302 ? ~1ua gnd current -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Reply by ●May 21, 20202020-05-21
On Thu, 21 May 2020 07:44:44 -0700 (PDT), Michael Terrell <terrell.michael.a@gmail.com> wrote:>On Thursday, May 21, 2020 at 10:35:09 AM UTC-4, jla...@highlandsniptechnology.com wrote: >> On Thu, 21 May 2020 01:55:31 -0700 (PDT), Michael Terrell Wrote: >> > >> >We were just starting to automate testing, but that was almost 19 years ago. Documentation and board or model number matched the blank board, plus the BOM and test procedure for different versions but with over 20 modules in a unit, plus a separate plug in tuner for older models (depending on which microwave band) still complicated issues. Add that the company had been around since 1968 which was before most small businesses used computers, the system was deeply embedded in the daily operations. They had changed their part numbering system, once and it was a nightmare. Every BOM had to be rewritten, on a typewriter, then all old copies destroyed. >> > >> > On top of that, when they decided to close their original Rockville Maryland plant, the employees shredded every document in the vault, plus all working copies, leaving the engineers the task of reverse engineering the last complete units and to recreate the mountain of data. >> >> Some companies have a "configuration control" department, whose job is >> to control all the documents and their relationship, and make sure the >> right stuff gets manufactured and remembered. All documents have to be >> submitted to them. >> >> Makes sense; keeping this stuff organized is non-trivial, especially >> when mistakes can kill people. > > > We did a lot of work for NASA and NOAA. We supplied their 'Command Destruct Receivers. If one of those failed, a rocket could kill a lot of people.On the S1B moon rocket, there was one transistor that fired the destruct charge. It was the most tested and qualified transistor in history, and the only one on the rocket that was in a socket. I designed some flight hardware for the first stage, but it was noncritical telemetry so only got the normal levels of QC paranoia. We etched our own PC boards in the bathroom and got away with it. -- John Larkin Highland Technology, Inc Science teaches us to doubt. Claude Bernard
Reply by ●May 21, 20202020-05-21
On Tue, 19 May 2020 09:55:39 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>On 2020-05-19 09:50, jlarkin@highlandsniptechnology.com wrote: >> On Tue, 19 May 2020 12:50:44 +0530, Pimpom <nobody@nowhere.com> wrote: >> >>> On 5/19/2020 9:31 AM, jlarkin@highlandsniptechnology.com wrote: >>>> On Mon, 18 May 2020 17:57:06 -0700 (PDT), >>>> bloggs.fredbloggs.fred@gmail.com wrote: >>>> >>>>> On Monday, May 18, 2020 at 7:41:34 PM UTC-4, John Larkin wrote: >>>>>> ST makes a nice little LDO, super-low dropout with an aux Vbias >>>>>> supply. Saves me from rolling my own with an opamp and a mosfet. >>>>>> >>>>>> It's an ST1L08. >>>>>> >>>>>> So why is the data sheet file en.DM00123507.pdf ? >>>>> >>>>> Who cares, it's a crappy regulator. And the lying bastards with their fake dropout specs while conveniently omitting the fact that Vbias must be greater than Vout + 1.5V. >>>> >>>> Lying? It's all over the data sheet. It's how they get the millivolts >>>> of dropout. I do that when I make my own super-LDOs, power an opamp >>>> from some higher voltage and over-drive an nfet follower down to >>>> milliohms of Rds-on. >>>> >>>>> The GND current at no load of 35uA, sucks , as does that showy 80dB PSRR at 100 Hz. Battery operation usually doesn't care a whole lot about PSRR. And the thermal impedance specs are so bad, you just try getting 800mA out of it with any kind voltage headroom without using a liquid nitrogen drip. >>>>> >>>> >>>> I'm dropping a switched 1.8 to 1.5. That's 0.3 volts. Times 800 mA >>>> would be 0.24 watts dissipated. Actually, I don't need that much >>>> current to run a couple DRAM chips. >>>> >>> >>> Not directly comparable to the ST1L08 but the Holtek HT75xx-1 >>> series is nice. Max Vin 30V, 100mA, 2.5uA ground current, 25mV >>> drop-out. 16 different fixed output voltages from 2.1V to 12V >>> with 3% tolerance. As usual with products originating in the >>> East, the datasheet is rather sparse about details, but I've used >>> them and they do what I want. >> >> Is it stable with low ESR caps? We use polymers or ceramics mostly. >> >> We need so many goofy voltages that we usually buy adjustable >> regulators for stock. The board that I'm doing now has a 24-channel >> analog mux to BIST the power supplies, using the dreadful Xilinx >> 1-volt XADC that's inside their FPGAs. Free and worth it. >> >>> >>>> You sure are in a bad mood lately. >>>> >>> I've noticed that lately with some regulars here, including a few >>> who normally exhibit decent manners. >> >> Well, some never show any sign of manners. They are repulsive but >> you've got to feel sorry for them, stuck being around themselves all >> day. >> >> There's a basically perfect -1 correlation between being obnoxious and >> designing electronics. > >Well, now that Jim Thompson is apparently no longer with us. :( > >He was a bit of a statistical outlier.He was crabby and dismissive of people not as smart as he was, and hostile to people that might have been smarter, but he was occasionally helpful, and had a sense of humor, and was very brave at the end. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●May 21, 20202020-05-21
On Thu, 21 May 2020 04:38:47 +0000 (UTC), Cydrome Leader <presence@MUNGEpanix.com> wrote:>John Larkin <jlarkin@highland_atwork_technology.com> wrote: >> On Wed, 20 May 2020 14:07:53 -0700 (PDT), Michael Terrell >> <terrell.michael.a@gmail.com> wrote: >> >>>On Wednesday, May 20, 2020 at 12:09:51 PM UTC-4, John Larkin wrote: >>>> >>>> In our system, if you know any drawing or product part number, you >>>> automatically know all the related ones. >>>> >>>> We refer to people by their names >>> >>> >>> Some boards and modules were used in multiple product lines, so your system wouldn't have worked at Microdyne. It was a different market, requiring different methods. For instance: The 700 and 1620-base models shared a lot of boards, and the front panel/embedded controller was also used in the custom system built for NOAA to control their 100 foot dishes that track their LEO birds. Each board or model had it's own base model number, and some had over 20 versions because customers wanted different options, Some of their first products were still in use 24/7 for over 30 years at NASA, tracking deep space satellites. They had never been turned off, or repaired. >> >> We reuse boards, and assemblies, in multiple prducts. If there are >> different versions, each has its own dash number and associated BOM. >> That's standard mil practice. > >do you have to relabel parts to give them the correct (for the end user) >part number? Sometimes there's goofiness with OEMed parts and trying to >re-order them. I've gotten parts with say a different brand printed on >them.We mostly sell products that we design and build. About the only things we sell unmodified are wall-warts and a few cables, and we do give those our own part numbers. A customer orders a 12-volt wart as a model J12, and it has internal stock number 726-2012, which in turn has a list of qualified sources. We don't encourage people to repair our stuff themselves, but if they do need a part, like a transformer or connector or something, we generally give them one.> >> >> In the aircraft business, xxxxx was a drawing and xxxxx-1 was a thing, >> and xxxxx-2 was its mirror image thing. Odds and evens were mirrors, >> like wings maybe, without requiring two drawings. We don't mirror >> parts, so for us -1 and -2 are just assembly versions of some sort. > >Were there ever "funny" issues with mirror image parts, like the left part >ended up with english thread fasteners or something dumb like that?I wonder if they tapped reverse threads!> >>> Completed units had custom build list, per the contract and all the test data for a unit was stored long term. The ISO inspectors spent most of their time looking at the files, since a record for one unit could be a half inch thick. That was why I pushed to change the test procedures to streamline them.It reduced the paperwork by about 25%. Some were rewritten from scratch, because the designer had the steps out of order, wasting test time. You had to do the same step several times before they were updated. A test fixture I redesigned educed the test time from 7.5 hours to 18 minutes and gave a more repeatable result. I know that you dislike trimpots, but they were used to adjust gan in many circuits. Even with 1% resistors and capacitors, they were often out of spec since 14, 1% components were used per video filter. >> >> Most of our testing is automated now, and test reports get pushed up >> to a server, as both PDF and JSON files. We can easily extract >> statistics from the JSON files. > >How did this work say 20 or 30 years ago?No, test reports were paper and procedures were manual or much less automated than now. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●May 21, 20202020-05-21
On 2020-05-21 13:38, John Larkin wrote:> On Tue, 19 May 2020 09:55:39 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 2020-05-19 09:50, jlarkin@highlandsniptechnology.com wrote: >>> On Tue, 19 May 2020 12:50:44 +0530, Pimpom <nobody@nowhere.com> wrote: >>> >>>> On 5/19/2020 9:31 AM, jlarkin@highlandsniptechnology.com wrote: >>>>> On Mon, 18 May 2020 17:57:06 -0700 (PDT), >>>>> bloggs.fredbloggs.fred@gmail.com wrote: >>>>> >>>>>> On Monday, May 18, 2020 at 7:41:34 PM UTC-4, John Larkin wrote: >>>>>>> ST makes a nice little LDO, super-low dropout with an aux Vbias >>>>>>> supply. Saves me from rolling my own with an opamp and a mosfet. >>>>>>> >>>>>>> It's an ST1L08. >>>>>>> >>>>>>> So why is the data sheet file en.DM00123507.pdf ? >>>>>> >>>>>> Who cares, it's a crappy regulator. And the lying bastards with their fake dropout specs while conveniently omitting the fact that Vbias must be greater than Vout + 1.5V. >>>>> >>>>> Lying? It's all over the data sheet. It's how they get the millivolts >>>>> of dropout. I do that when I make my own super-LDOs, power an opamp >>>>> from some higher voltage and over-drive an nfet follower down to >>>>> milliohms of Rds-on. >>>>> >>>>>> The GND current at no load of 35uA, sucks , as does that showy 80dB PSRR at 100 Hz. Battery operation usually doesn't care a whole lot about PSRR. And the thermal impedance specs are so bad, you just try getting 800mA out of it with any kind voltage headroom without using a liquid nitrogen drip. >>>>>> >>>>> >>>>> I'm dropping a switched 1.8 to 1.5. That's 0.3 volts. Times 800 mA >>>>> would be 0.24 watts dissipated. Actually, I don't need that much >>>>> current to run a couple DRAM chips. >>>>> >>>> >>>> Not directly comparable to the ST1L08 but the Holtek HT75xx-1 >>>> series is nice. Max Vin 30V, 100mA, 2.5uA ground current, 25mV >>>> drop-out. 16 different fixed output voltages from 2.1V to 12V >>>> with 3% tolerance. As usual with products originating in the >>>> East, the datasheet is rather sparse about details, but I've used >>>> them and they do what I want. >>> >>> Is it stable with low ESR caps? We use polymers or ceramics mostly. >>> >>> We need so many goofy voltages that we usually buy adjustable >>> regulators for stock. The board that I'm doing now has a 24-channel >>> analog mux to BIST the power supplies, using the dreadful Xilinx >>> 1-volt XADC that's inside their FPGAs. Free and worth it. >>> >>>> >>>>> You sure are in a bad mood lately. >>>>> >>>> I've noticed that lately with some regulars here, including a few >>>> who normally exhibit decent manners. >>> >>> Well, some never show any sign of manners. They are repulsive but >>> you've got to feel sorry for them, stuck being around themselves all >>> day. >>> >>> There's a basically perfect -1 correlation between being obnoxious and >>> designing electronics. >> >> Well, now that Jim Thompson is apparently no longer with us. :( >> >> He was a bit of a statistical outlier. > > He was crabby and dismissive of people not as smart as he was, and > hostile to people that might have been smarter, but he was > occasionally helpful, and had a sense of humor, and was very brave at > the end. >When he wasn't busy accusing peoples' wives of immoral behaviour, threatening folks with lawsuits or bodily harm, or siccing the FBI on some deserving individuals. ;) He was probably nice enough in person--we collaborated a couple of times but never met in person or even talked on the phone together. I agree that he had guts and seems to have died very well. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●May 21, 20202020-05-21
On Thu, 21 May 2020 14:07:29 -0400, Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:>On 2020-05-21 13:38, John Larkin wrote: >> On Tue, 19 May 2020 09:55:39 -0400, Phil Hobbs >> <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> On 2020-05-19 09:50, jlarkin@highlandsniptechnology.com wrote: >>>> On Tue, 19 May 2020 12:50:44 +0530, Pimpom <nobody@nowhere.com> wrote: >>>> >>>>> On 5/19/2020 9:31 AM, jlarkin@highlandsniptechnology.com wrote: >>>>>> On Mon, 18 May 2020 17:57:06 -0700 (PDT), >>>>>> bloggs.fredbloggs.fred@gmail.com wrote: >>>>>> >>>>>>> On Monday, May 18, 2020 at 7:41:34 PM UTC-4, John Larkin wrote: >>>>>>>> ST makes a nice little LDO, super-low dropout with an aux Vbias >>>>>>>> supply. Saves me from rolling my own with an opamp and a mosfet. >>>>>>>> >>>>>>>> It's an ST1L08. >>>>>>>> >>>>>>>> So why is the data sheet file en.DM00123507.pdf ? >>>>>>> >>>>>>> Who cares, it's a crappy regulator. And the lying bastards with their fake dropout specs while conveniently omitting the fact that Vbias must be greater than Vout + 1.5V. >>>>>> >>>>>> Lying? It's all over the data sheet. It's how they get the millivolts >>>>>> of dropout. I do that when I make my own super-LDOs, power an opamp >>>>>> from some higher voltage and over-drive an nfet follower down to >>>>>> milliohms of Rds-on. >>>>>> >>>>>>> The GND current at no load of 35uA, sucks , as does that showy 80dB PSRR at 100 Hz. Battery operation usually doesn't care a whole lot about PSRR. And the thermal impedance specs are so bad, you just try getting 800mA out of it with any kind voltage headroom without using a liquid nitrogen drip. >>>>>>> >>>>>> >>>>>> I'm dropping a switched 1.8 to 1.5. That's 0.3 volts. Times 800 mA >>>>>> would be 0.24 watts dissipated. Actually, I don't need that much >>>>>> current to run a couple DRAM chips. >>>>>> >>>>> >>>>> Not directly comparable to the ST1L08 but the Holtek HT75xx-1 >>>>> series is nice. Max Vin 30V, 100mA, 2.5uA ground current, 25mV >>>>> drop-out. 16 different fixed output voltages from 2.1V to 12V >>>>> with 3% tolerance. As usual with products originating in the >>>>> East, the datasheet is rather sparse about details, but I've used >>>>> them and they do what I want. >>>> >>>> Is it stable with low ESR caps? We use polymers or ceramics mostly. >>>> >>>> We need so many goofy voltages that we usually buy adjustable >>>> regulators for stock. The board that I'm doing now has a 24-channel >>>> analog mux to BIST the power supplies, using the dreadful Xilinx >>>> 1-volt XADC that's inside their FPGAs. Free and worth it. >>>> >>>>> >>>>>> You sure are in a bad mood lately. >>>>>> >>>>> I've noticed that lately with some regulars here, including a few >>>>> who normally exhibit decent manners. >>>> >>>> Well, some never show any sign of manners. They are repulsive but >>>> you've got to feel sorry for them, stuck being around themselves all >>>> day. >>>> >>>> There's a basically perfect -1 correlation between being obnoxious and >>>> designing electronics. >>> >>> Well, now that Jim Thompson is apparently no longer with us. :( >>> >>> He was a bit of a statistical outlier. >> >> He was crabby and dismissive of people not as smart as he was, and >> hostile to people that might have been smarter, but he was >> occasionally helpful, and had a sense of humor, and was very brave at >> the end. >> > >When he wasn't busy accusing peoples' wives of immoral behaviour, >threatening folks with lawsuits or bodily harm, or siccing the FBI on >some deserving individuals. ;)Gosh, nobody's perfect.> >He was probably nice enough in person--we collaborated a couple of times >but never met in person or even talked on the phone together. > >I agree that he had guts and seems to have died very well.I used a version of his clever CD ignition (without his permission) as a gain-switched laser driver. Nice circuit. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●May 21, 20202020-05-21
On 2020-05-21 16:44, John Larkin wrote:> On Thu, 21 May 2020 14:07:29 -0400, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 2020-05-21 13:38, John Larkin wrote: >>> On Tue, 19 May 2020 09:55:39 -0400, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> On 2020-05-19 09:50, jlarkin@highlandsniptechnology.com wrote: >>>>> On Tue, 19 May 2020 12:50:44 +0530, Pimpom <nobody@nowhere.com> wrote: >>>>> >>>>>> On 5/19/2020 9:31 AM, jlarkin@highlandsniptechnology.com wrote: >>>>>>> On Mon, 18 May 2020 17:57:06 -0700 (PDT), >>>>>>> bloggs.fredbloggs.fred@gmail.com wrote: >>>>>>> >>>>>>>> On Monday, May 18, 2020 at 7:41:34 PM UTC-4, John Larkin wrote: >>>>>>>>> ST makes a nice little LDO, super-low dropout with an aux Vbias >>>>>>>>> supply. Saves me from rolling my own with an opamp and a mosfet. >>>>>>>>> >>>>>>>>> It's an ST1L08. >>>>>>>>> >>>>>>>>> So why is the data sheet file en.DM00123507.pdf ? >>>>>>>> >>>>>>>> Who cares, it's a crappy regulator. And the lying bastards with their fake dropout specs while conveniently omitting the fact that Vbias must be greater than Vout + 1.5V. >>>>>>> >>>>>>> Lying? It's all over the data sheet. It's how they get the millivolts >>>>>>> of dropout. I do that when I make my own super-LDOs, power an opamp >>>>>>> from some higher voltage and over-drive an nfet follower down to >>>>>>> milliohms of Rds-on. >>>>>>> >>>>>>>> The GND current at no load of 35uA, sucks , as does that showy 80dB PSRR at 100 Hz. Battery operation usually doesn't care a whole lot about PSRR. And the thermal impedance specs are so bad, you just try getting 800mA out of it with any kind voltage headroom without using a liquid nitrogen drip. >>>>>>>> >>>>>>> >>>>>>> I'm dropping a switched 1.8 to 1.5. That's 0.3 volts. Times 800 mA >>>>>>> would be 0.24 watts dissipated. Actually, I don't need that much >>>>>>> current to run a couple DRAM chips. >>>>>>> >>>>>> >>>>>> Not directly comparable to the ST1L08 but the Holtek HT75xx-1 >>>>>> series is nice. Max Vin 30V, 100mA, 2.5uA ground current, 25mV >>>>>> drop-out. 16 different fixed output voltages from 2.1V to 12V >>>>>> with 3% tolerance. As usual with products originating in the >>>>>> East, the datasheet is rather sparse about details, but I've used >>>>>> them and they do what I want. >>>>> >>>>> Is it stable with low ESR caps? We use polymers or ceramics mostly. >>>>> >>>>> We need so many goofy voltages that we usually buy adjustable >>>>> regulators for stock. The board that I'm doing now has a 24-channel >>>>> analog mux to BIST the power supplies, using the dreadful Xilinx >>>>> 1-volt XADC that's inside their FPGAs. Free and worth it. >>>>> >>>>>> >>>>>>> You sure are in a bad mood lately. >>>>>>> >>>>>> I've noticed that lately with some regulars here, including a few >>>>>> who normally exhibit decent manners. >>>>> >>>>> Well, some never show any sign of manners. They are repulsive but >>>>> you've got to feel sorry for them, stuck being around themselves all >>>>> day. >>>>> >>>>> There's a basically perfect -1 correlation between being obnoxious and >>>>> designing electronics. >>>> >>>> Well, now that Jim Thompson is apparently no longer with us. :( >>>> >>>> He was a bit of a statistical outlier. >>> >>> He was crabby and dismissive of people not as smart as he was, and >>> hostile to people that might have been smarter, but he was >>> occasionally helpful, and had a sense of humor, and was very brave at >>> the end. >>> >> >> When he wasn't busy accusing peoples' wives of immoral behaviour, >> threatening folks with lawsuits or bodily harm, or siccing the FBI on >> some deserving individuals. ;) > > Gosh, nobody's perfect. > >> >> He was probably nice enough in person--we collaborated a couple of times >> but never met in person or even talked on the phone together. >> >> I agree that he had guts and seems to have died very well. > > I used a version of his clever CD ignition (without his permission) as > a gain-switched laser driver. Nice circuit. >I have a mirror of the last version of his web site at <https://electrooptical.net/static/oldsite/www.analog-innovations.com/logo.html>. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●May 21, 20202020-05-21
On 2020-05-21 12:18, jlarkin@highlandsniptechnology.com wrote:> On Thu, 21 May 2020 07:44:44 -0700 (PDT), Michael Terrell > <terrell.michael.a@gmail.com> wrote: > >> On Thursday, May 21, 2020 at 10:35:09 AM UTC-4, jla...@highlandsniptechnology.com wrote: >>> On Thu, 21 May 2020 01:55:31 -0700 (PDT), Michael Terrell Wrote: >>>> >>>> We were just starting to automate testing, but that was almost 19 years ago. Documentation and board or model number matched the blank board, plus the BOM and test procedure for different versions but with over 20 modules in a unit, plus a separate plug in tuner for older models (depending on which microwave band) still complicated issues. Add that the company had been around since 1968 which was before most small businesses used computers, the system was deeply embedded in the daily operations. They had changed their part numbering system, once and it was a nightmare. Every BOM had to be rewritten, on a typewriter, then all old copies destroyed. >>>> >>>> On top of that, when they decided to close their original Rockville Maryland plant, the employees shredded every document in the vault, plus all working copies, leaving the engineers the task of reverse engineering the last complete units and to recreate the mountain of data. >>> >>> Some companies have a "configuration control" department, whose job is >>> to control all the documents and their relationship, and make sure the >>> right stuff gets manufactured and remembered. All documents have to be >>> submitted to them. >>> >>> Makes sense; keeping this stuff organized is non-trivial, especially >>> when mistakes can kill people. >> >> >> We did a lot of work for NASA and NOAA. We supplied their 'Command Destruct Receivers. If one of those failed, a rocket could kill a lot of people. > > On the S1B moon rocket, there was one transistor that fired the > destruct charge. It was the most tested and qualified transistor in > history, and the only one on the rocket that was in a socket.After all that handling and abuse, it was probably among the least reliable, too. ;)> > I designed some flight hardware for the first stage, but it was > noncritical telemetry so only got the normal levels of QC paranoia. > > We etched our own PC boards in the bathroom and got away with it.At IBM, if you needed to commit a safety violation to get your work done, savvy folks did it in their offices, not their labs. Nobody ever did a hazardous chemical audit of the offices for some reason. ;) It was pretty tame stuff usually--my lab didn't have a fume hood, and I needed to be able to etch patterns into metallized PVDF. I kept a RadioShack bottle of FeCl2 juice in my office, which was across the hall from my lab, and shuttled some back and forth as necessary. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●May 21, 20202020-05-21
On Tuesday, May 19, 2020 at 1:41:34 AM UTC+2, John Larkin wrote:> ST makes a nice little LDO, super-low dropout with an aux Vbias > supply. Saves me from rolling my own with an opamp and a mosfet. > > It's an ST1L08. > > So why is the data sheet file en.DM00123507.pdf ? >When I google it, it comes up as: https://www.st.com/resource/en/datasheet/st1l08.pdf Cheers KLaus Bytheway, funny video, google spelling: https://www.youtube.com/watch?v=fno1T-GyKXw
