On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid <martin_riddle@verison.net> wrote:>John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r >> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in >certainties.Francis Bacon > >Medical equipment. > >CheersYikes. It scares me to imagine anyone doing field repairs to medical equipment. Our gear is always returned to the factory for repairs. We can replace any bad parts with the correct part, QC the work, then run the full automated test and cal and archive a test report. And we learn about failure rates and mechanisms.
Waveform documentation
Started by ●June 26, 2022
Reply by ●June 28, 20222022-06-28
Reply by ●June 28, 20222022-06-28
On 28/06/2022 13:28, jlarkin@highlandsniptechnology.com wrote:> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid > <martin_riddle@verison.net> wrote: > >> John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r >>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in >> certainties.Francis Bacon >> >> Medical equipment. >> >> Cheers > > Yikes. It scares me to imagine anyone doing field repairs to medical > equipment.It is also a bit scary to imagine being treated in a hospital during an emergency, full of equipment that when it fails, cannot be repaired in the field, but must instead be sent to the same overseas facility that every other hospital in the world is trying to send their dead units to, (especially bearing in mind that whatever emergency may well put all the freight aircraft or their pilots out of action). There is an argument for only procuring medical equipment with proper service manuals, resistors big enough to have values marked on them, and a stock of spares of any programmable devices, or spares of any boards with massive BGAs, and no parts locked to each other by serial number. Those countries with nationalised healthcare do have sufficient buying power to dictate those terms if they want to, (much like the US military to test equipment manufacturers in the past).
Reply by ●June 28, 20222022-06-28
On Tue, 28 Jun 2022 16:19:23 +1000, Chris Jones <lugnut808@spam.yahoo.com> wrote:>On 28/06/2022 13:28, jlarkin@highlandsniptechnology.com wrote: >> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid >> <martin_riddle@verison.net> wrote: >> >>> John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r >>>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in >>> certainties.Francis Bacon >>> >>> Medical equipment. >>> >>> Cheers >> >> Yikes. It scares me to imagine anyone doing field repairs to medical >> equipment. > >It is also a bit scary to imagine being treated in a hospital during an >emergency, full of equipment that when it fails, cannot be repaired in >the field, but must instead be sent to the same overseas facility that >every other hospital in the world is trying to send their dead units to, >(especially bearing in mind that whatever emergency may well put all the >freight aircraft or their pilots out of action). > >There is an argument for only procuring medical equipment with proper >service manuals, resistors big enough to have values marked on them, and >a stock of spares of any programmable devices, or spares of any boards >with massive BGAs, and no parts locked to each other by serial number. >Those countries with nationalised healthcare do have sufficient buying >power to dictate those terms if they want to, (much like the US military >to test equipment manufacturers in the past). >No surface-mount? Our FDA is absolutely fascist about quality. They pulled a pop inspection on one nearby outfit that made cancer-treatment gear. They discovered some new pcb's on the same bench as some repair units, which is against the rules. They shut down the facility for a year of re-training and re-qualification, and some of the engineers quit from boredom.
Reply by ●June 28, 20222022-06-28
jlarkin@highlandsniptechnology.com Wrote in message:r> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in>certainties.Francis Bacon>>Medical equipment. >>CheersYikes. It scares me to imagine anyone doing field repairs to medicalequipment.Our gear is always returned to the factory for repairs. We can replaceany bad parts with the correct part, QC the work, then run the fullautomated test and cal and archive a test report.And we learn about failure rates and mechanisms.Ok, how about automotive service manuals. Feel better? ;) Cheers -- ----Android NewsGroup Reader---- https://piaohong.s3-us-west-2.amazonaws.com/usenet/index.html
Reply by ●June 28, 20222022-06-28
On Tue, 28 Jun 2022 07:16:13 -0700, jlarkin@highlandsniptechnology.com wrote:>On Tue, 28 Jun 2022 16:19:23 +1000, Chris Jones ><lugnut808@spam.yahoo.com> wrote: > >>On 28/06/2022 13:28, jlarkin@highlandsniptechnology.com wrote: >>> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid >>> <martin_riddle@verison.net> wrote: >>> >>>> John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r >>>>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in >>>> certainties.Francis Bacon >>>> >>>> Medical equipment. >>>> >>>> Cheers >>> >>> Yikes. It scares me to imagine anyone doing field repairs to medical >>> equipment. >> >>It is also a bit scary to imagine being treated in a hospital during an >>emergency, full of equipment that when it fails, cannot be repaired in >>the field, but must instead be sent to the same overseas facility that >>every other hospital in the world is trying to send their dead units to, >>(especially bearing in mind that whatever emergency may well put all the >>freight aircraft or their pilots out of action). >> >>There is an argument for only procuring medical equipment with proper >>service manuals, resistors big enough to have values marked on them, and >>a stock of spares of any programmable devices, or spares of any boards >>with massive BGAs, and no parts locked to each other by serial number. >>Those countries with nationalised healthcare do have sufficient buying >>power to dictate those terms if they want to, (much like the US military >>to test equipment manufacturers in the past). >> > >No surface-mount? > >Our FDA is absolutely fascist about quality. They pulled a pop >inspection on one nearby outfit that made cancer-treatment gear. They >discovered some new pcb's on the same bench as some repair units, >which is against the rules. They shut down the facility for a year of >re-training and re-qualification, and some of the engineers quit from >boredom.Yes. Here's why: .<https://en.wikipedia.org/wiki/Therac-25> I read the what-happened reports from the day. What a bunch of hacks, even by the standards of that day. Joe Gwinn
Reply by ●June 28, 20222022-06-28
On 6/28/2022 12:35 PM, Joe Gwinn wrote:> On Tue, 28 Jun 2022 07:16:13 -0700, jlarkin@highlandsniptechnology.com > wrote: > >> On Tue, 28 Jun 2022 16:19:23 +1000, Chris Jones >> <lugnut808@spam.yahoo.com> wrote: >> >>> On 28/06/2022 13:28, jlarkin@highlandsniptechnology.com wrote: >>>> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid >>>> <martin_riddle@verison.net> wrote: >>>> >>>>> John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r >>>>>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in >>>>> certainties.Francis Bacon >>>>> >>>>> Medical equipment. >>>>> >>>>> Cheers >>>> >>>> Yikes. It scares me to imagine anyone doing field repairs to medical >>>> equipment. >>> >>> It is also a bit scary to imagine being treated in a hospital during an >>> emergency, full of equipment that when it fails, cannot be repaired in >>> the field, but must instead be sent to the same overseas facility that >>> every other hospital in the world is trying to send their dead units to, >>> (especially bearing in mind that whatever emergency may well put all the >>> freight aircraft or their pilots out of action). >>> >>> There is an argument for only procuring medical equipment with proper >>> service manuals, resistors big enough to have values marked on them, and >>> a stock of spares of any programmable devices, or spares of any boards >>> with massive BGAs, and no parts locked to each other by serial number. >>> Those countries with nationalised healthcare do have sufficient buying >>> power to dictate those terms if they want to, (much like the US military >>> to test equipment manufacturers in the past). >>> >> >> No surface-mount? >> >> Our FDA is absolutely fascist about quality. They pulled a pop >> inspection on one nearby outfit that made cancer-treatment gear. They >> discovered some new pcb's on the same bench as some repair units, >> which is against the rules. They shut down the facility for a year of >> re-training and re-qualification, and some of the engineers quit from >> boredom. > > Yes. Here's why: > > .<https://en.wikipedia.org/wiki/Therac-25> > > I read the what-happened reports from the day. What a bunch of hacks, > even by the standards of that day.Sadly, there isn't much that can really be done to improve things, short of insisting on "process" -- and "proof" of adherence to same. Some of my customers were even more zealous -- checking into the qualifications of the engineers working on the design, wanting to review component choices (for suitability as well as long-term availability/second sources), insisting on placing the complete design in escrow, etc. I guess when it's YOUR ass on the line, you can never be too careful! OTOH, you CHARGE them for these "inconveniences" (even though they improve the quality of YOUR product!)
Reply by ●June 28, 20222022-06-28
On Tue, 28 Jun 2022 14:19:58 -0400 (EDT), Martin Rid <martin_riddle@verison.net> wrote:>jlarkin@highlandsniptechnology.com Wrote in message:r >> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would >apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in>certainties.Francis Bacon>>Medical equipment. >>CheersYikes. It scares me to imagine anyone doing field repairs to medicalequipment.Our gear is always returned to the factory for repairs. We can replaceany bad parts with the correct part, QC the work, then run the fullautomated test and cal and archive a test report.And we learn about failure rates and mechanisms. > >Ok, how about automotive service manuals. >Feel better? >;) >CheersA lot of stuff on my car can't be fixed by owners. -- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in certainties. Francis Bacon
Reply by ●June 28, 20222022-06-28
On 29/06/2022 00:16, jlarkin@highlandsniptechnology.com wrote:> On Tue, 28 Jun 2022 16:19:23 +1000, Chris Jones > <lugnut808@spam.yahoo.com> wrote: > >> On 28/06/2022 13:28, jlarkin@highlandsniptechnology.com wrote: >>> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid >>> <martin_riddle@verison.net> wrote: >>> >>>> John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r >>>>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Don Y <blockedofcourse@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in >>>> certainties.Francis Bacon >>>> >>>> Medical equipment. >>>> >>>> Cheers >>> >>> Yikes. It scares me to imagine anyone doing field repairs to medical >>> equipment. >> >> It is also a bit scary to imagine being treated in a hospital during an >> emergency, full of equipment that when it fails, cannot be repaired in >> the field, but must instead be sent to the same overseas facility that >> every other hospital in the world is trying to send their dead units to, >> (especially bearing in mind that whatever emergency may well put all the >> freight aircraft or their pilots out of action). >> >> There is an argument for only procuring medical equipment with proper >> service manuals, resistors big enough to have values marked on them, and >> a stock of spares of any programmable devices, or spares of any boards >> with massive BGAs, and no parts locked to each other by serial number. >> Those countries with nationalised healthcare do have sufficient buying >> power to dictate those terms if they want to, (much like the US military >> to test equipment manufacturers in the past). >> > > No surface-mount?I'd say 0603 is fine, they don't require special equipment, anything much smaller (and BGAs etc.) ought to be discouraged except where really necessary, and in those cases the customer should probably be allowed to stock spare boards instead. And I'm not saying the repairers need not have any qualifications, just that procurement policy (and IP law) should ensure that the manufacturer cannot unduly hinder emergency repairs of medical devices by withholding documentation and software.
Reply by ●June 29, 20222022-06-29
On Tuesday, June 28, 2022 at 7:52:48 PM UTC-4, John Larkin wrote:> On Tue, 28 Jun 2022 14:19:58 -0400 (EDT), Martin Rid > <martin...@verison.net> wrote: > > >jla...@highlandsniptechnology.com Wrote in message:r > >> On Mon, 27 Jun 2022 20:49:18 -0400 (EDT), Martin Rid<martin...@verison.net> wrote:>John Larkin <jlarkin@highland_atwork_technology.com> Wrote in message:r>> On Mon, 27 Jun 2022 14:27:07 -0400 (EDT), Martin Rid<martin...@verison.net> wrote:>Don Y <blocked...@foo.invalid> Wrote in message:r>> I usually build a document that describes the hardware,nominal voltages, waveforms, timing relationships, etc.Plus, captured waveforms under different operating conditions(along with those expected during specific diagnostics)I'm getting some pushback to move these onto the schematics,directly, instead of in a supplementary document.I'm not keen on this as it means schematics have to make roomto accommodate these annotations. And, I can't see how tomaintain such a document if light of potential changes todiagnostics (which may be numerous for a given circuit).Any folks preparing comparable documentation have suggestions?>>I would imagine a separate service manual would > >apply.>>CheersDoes anyone still do that?-- If a man will begin with certainties, he shall end with doubts, but if he will be content to begin with doubts he shall end in>certainties.Francis Bacon>>Medical equipment. >>CheersYikes. It scares me to imagine anyone doing field repairs to medicalequipment.Our gear is always returned to the factory for repairs. We can replaceany bad parts with the correct part, QC the work, then run the fullautomated test and cal and archive a test report.And we learn about failure rates and mechanisms. > > > >Ok, how about automotive service manuals. > >Feel better? > >;) > >Cheers > A lot of stuff on my car can't be fixed by owners. > -- > > If a man will begin with certainties, he shall end with doubts, > but if he will be content to begin with doubts he shall end in certainties. > Francis BaconDesign and mfg for repairability for most consumer products went away decades ago. Throw away society and if you believe they work, electronic recycling facilities. Have relatives in the Boston area. Extended visits usually resulted in taking refuse to the local 'dump'...The dump had a sizable building with tables where ppl would put their (mostly electronic) stuff for recycling. Back in the day, retrieved a Apple power station (dead supply-easily fixed), 32" color tv ( short in HV section), Marantz 60watts am/fm receiver ( blown output transistors). One mans ceiling is another mans floor. J J
Reply by ●June 29, 20222022-06-29
On 6/28/2022 9:21 PM, Three Jeeps wrote:> Design and mfg for repairability for most consumer products went away > decades ago.Simple matter of labor costs. As product *price* falls, there's less and less room to accommodate repair/refurbishing. Sadly, "consumer" isn't the only market suffering from that affliction; businesses (here) routinely replace ALL of their workstations on short update cycles (18-36 months). Even KEYBOARDS have longer useful lives than that (and they experience the most wear). I see a lot of medical equipment (and DME), medicines, bicycles, scooters, wheelchairs, phones, copiers, etc. headed to the tip.> Throw away society and if you believe they work, electronic > recycling facilities.IME, all this does is get yesterday's kit into the hands of The Less Fortunate. E.g., a group I'm affiliated with refurbishes hundreds of PCs each month, distributing them for low/no cost ($20) to folks who are more needy. So, on the one hand, the item has been (temporarily) diverted from the land fill; on the other, we've effectively just created another *user* (and, there's likely no one "beneath" him when *he* discards the refurbished unit) The DME is perhaps the most disheartening because you know it represents a "real" need -- for someone. (yet, you often can't give the stuff away because what the recipient needs more than anything is the support that comes with a commercial sale!)> Have relatives in the Boston area. Extended visits > usually resulted in taking refuse to the local 'dump'...The dump had a > sizable building with tables where ppl would put their (mostly electronic) > stuff for recycling. Back in the day, retrieved a Apple power station > (dead supply-easily fixed), 32" color tv ( short in HV section), Marantz > 60watts am/fm receiver ( blown output transistors). One mans ceiling is > another mans floor.I have 30 monitors (12 in use) that I've recapped or replaced blown FETs. Two laser printers (including several NIB toner cartridges). Discarded the color phasers, LaserJet 4M+ (w/duplexor), etc. cuz it was silly to maintain them given how little color printing I do (I can color print at the library -- from home! -- for $0.10/page). Two B-size ("Tabloid") flat bed scanners. A 40" wide format scanner. A couple of sheet-fed scanners. Half a dozen motion controllers. Box of mice and keyboards. A couple of digitizing tablets (discarded the D-size unit as it took up too much floor space). Discarded the pen plotters for similar reasons. Countless bits of test equipment -- usually just needing a recal cycle or trivial repair. Six laptops -- each in a carrying bag. Several servers. Six identical workstations. A dozen 1500VA sine-wave, networked UPSs. (plus several 2200-5000VA units). Each item "bought" for the scrap price that the "material recycler" would pay for them NOT broken down into their component parts (normally, items are disassembled so fans can be sold to one recycler, PCBs to another, tin/metal to a third, etc.). This because there are no users eager to inherit an 80 pound workstation or an oversized scanner, or a monitor with broken backlight PS, etc. [If you truly understood the magnitude of the throw-away problem, you'd approach design entirely differently!]
