why do they do this?

LOL! That's a good one...

That depends. I'm sure that datasheets are a very small part of their corporate documents, and within the company it works for them.

If they did it by part name, it should include the company name, and the date that it was released. For example: DevName-TI-2020-05

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g multiple versions from one vendor, plus second sources, all with the same file name. Some jellybean parts have dozens of versions of a datasheet.

system. His concept was that the part number for a 1K resistor would be 100

1. He threw a real hissy fit when I pointed out that we stocked 14 differen t 1K resistors, and other components had a value of 1002. He wasn't there v ery long before they fired him.

odel numbers. They were filed by model number, but under ISO9001 we had to have traceability for all revisions. One board had 14 versions, and 14 test procedures. Every one ended up with over 100 lines that had to be marked N /A. I wrote a new procedure to cover every version of the board. It had 14 datasheets, one per version with no extra lines, plus a spare to allow for you to add new versions. The first page clearly stated to only use the spec ified datasheet for the version being tested. It reduced both the test time , and the paperwork to be stored. There are reasons to use other than obvio us file naming. I am currently going through thousands of PDF files for tes t equipment. I am adding the actual document numbers to the file names, not just 'HP3325' since the A and B versions are different, but the manuals we re revised multiple times. I have 180 GB of files, over 32,000 of them to s ort, rename and compare.

nual I come across.

There were still reference to some trucks in the Microdyne inventory, along with all the test equipment. The founders of the company mad the Cal Lab k eep their records in the database rather than their own system. It was on a Prime mini computer with about fifty terminals scattered all over the comp lex. Those trucks were gone, but they had been used to install their C-band equipment in head ends, and businesses before they shut down that product line.

Haven't ANs always been like that though? Just sort of sequential numbers for the most part that you might get faxed or mailed over? Computer/software Knowlege Base stuff is similar, they just use a series of numbers, since trying to locate a specific document without an exact number is almost pointless if you tried to search for common terms. I can forgive nearly meaningless file naming for those. Components are physical devices with exact part numbers, not concepts or procedures. They deserve documentation tied to that part number.

Notice how so far nobody has said "damn it, I'd rename 74S161.PDF into en.87784636y4ehfh5476f.PDF as I drop it into my really helpful document management system".

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 sys tem 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 cu stom system built for NOAA to control their 100 foot dishes that track thei r LEO birds. Each board or model had it's own base model number, and some h ad over 20 versions because customers wanted different options, Some of the ir first products were still in use 24/7 for over 30 years at NASA, trackin g deep space satellites. They had never been turned off, or repaired.

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 the ir time looking at the files, since a record for one unit could be a half i nch thick. That was why I pushed to change the test procedures to streamlin e them.It reduced the paperwork by about 25%. Some were rewritten from scra tch, because the designer had the steps out of order, wasting test time. Yo u had to do the same step several times before they were updated. A test fi xture I redesigned educed the test time from 7.5 hours to 18 minutes and ga ve a more repeatable result. I know that you dislike trimpots, but they wer e used to adjust gan in many circuits. Even with 1% resistors and capacitor s, they were often out of spec since 14, 1% components were used per video filter.

I think it is to allow good customers early access to the documents. You can guesss the document name from the device they announced.

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.

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.

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.

What was the company with "dyne" in the name that made super high density connectors? I sort of miss the fad based company names of the past. "dyne" was hot, then anything spelled with a Z or X. Lots of "International" for stuff a little as having a sales rep in Canda or something as token. Trying to think of some other amusing naming patterns of the past.

Haha. I tried to post data on a company system as my employee ID instead of name. It caused lots of confusion and got some folks bent out of shape.

That's impressive. What was the design life of this equipment in the first place? I get excited if 30 year old test equipment fires up, without an actual fire. I'm even more shocked if CFL bulbs can last a year.

So it NASA sitting on faded out dot matrix printouts of test data nobody can read anymore? How do you file away test data from ages ago?

The last open frame linear power supplies I got still had the goofy folded up dot matrix "report" stuffed inside of them. I can only imagine the test rack they use for that stuff is so old it has a black crinkle finish and giant bakelite handwheels and some Okidata printer jammed in there.

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.

Were there ever "funny" issues with mirror image parts, like the left part ended up with english thread fasteners or something dumb like that?

How did this work say 20 or 30 years ago?

Was that the guy who designed all the 2 digit LM series chips? What happened to him?

ir fake dropout specs while conveniently omitting the fact that Vbias must be greater than Vout + 1.5V.

PSRR at 100 Hz. Battery operation usually doesn't care a whole lot about P SRR. 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 d rip.

You are thinking of Bob Widlar, and Wikipedia will tell you all you need to know. He seems to have drunk to much and died relatively young - aged

Jim Thompson designed a bunch of chip for Motorola early on, and I had the dubious pleasure of getting a few of them to work. It wasn't easy, and ever y last one of them got replaced by something that had been designed to do m uch the same job either a bit better or bit more easily.

The MC14046 comes to mind. It's Jim's TTL MC4024 and MC4044 combined and ex ecuted in CMOS by somebody else. It's still a conceptual mess but works wel l enough to have lasted.

Jim's multiplier chips were much the same as the multiplier chips Barry Gi lbert put together for Analog Devices, but every last one of Barry's parts was easier to use than Jim's, and Barry kept on tinkering with them to make the better - faster or more accurate - for some years. I met Barry once wh en I was working in the UK and he was going around talking to customers, es sentially about new products that we weren't going to be buying.

Jim was an adequate journey man designer, and Bob and Barry were master cra ftsmen. Bob seems to nave been a real virtuoso.

He was more in the Motorola orbit back then, IIRC, but he was certainly the most accomplished IC designer in the group. He disappeared a couple of years ago, after having been diagnosed with early-stage pancreatic cancer during tests for something else. He said that he thought he had beaten it, but then just disappeared from the group. His website subsequently disappeared as well.

Various folks have looked for an obituary, but nothing turned up. (His full name was James Elbert Thompson, and he lived most recently in Queen Creek AZ.) He was a bit of a chingada but designed a lot of interesting electronics and really helped keep the local leftists in check.

Cheers

Phil Hobbs

The only one who did it for a livng.

I didn't much like it when he found out my postal address in the Netherland's and threatened to send a couple of hit men to keep me in check.

His apologists claimed that he was just joking, but he persisted in his claim to have to reported me to the FBI for dangerously anti-American attitudes.

I'm certainly more left of centre than Jim was - you'd have to rabid to get further to the right - and I'm almost certainly to the left of Phil Hobbs.

This doesn't make me a leftist outside of the US. where they are plenty of peole who are much further to the left.

As for keeping me - or anybody else - "in check", Phil is fooling himself. In chess this means putting enough pressure on the king to force some kind of counter move to get it out of check, and I've not experienced anything like that.

I once - unwisely - took up John Larkin when he claimed that he couldn't find enough competent help, and suggested that I might be able to do some remote consulting for him.

John Larkin then behaved rather badly by passing on the e-mail to Jim, who proceeded to crow - here - about persuading John not to follow up.

He didn't have anything to crow about. John's passing on the e-mail to Jim would have been quite enough to put me right off the idea, anyway. You have to trust the people you work with to behave more or less properly, and John clearly couldn't be trusted.

system wouldn't have worked at Microdyne. It was a different market, requir ing 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 t heir LEO birds. Each board or model had it's own base model number, and som e 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, trac king deep space satellites. They had never been turned off, or repaired.

est 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 hal f inch thick. That was why I pushed to change the test procedures to stream line them.It reduced the paperwork by about 25%. Some were rewritten from s cratch, 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 capaci tors, they were often out of spec since 14, 1% components were used per vid eo filter.

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 aro und since 1968 which was before most small businesses used computers, the s ystem was deeply embedded in the daily operations. They had changed their p art numbering system, once and it was a nightmare. Every BOM had to be rewr itten, on a typewriter, then all old copies destroyed.

On top of that, when they decided to close their original Rockville Mary land plant, the employees shredded every document in the vault, plus all wo rking copies, leaving the engineers the task of reverse engineering the las t complete units and to recreate the mountain of data.

The files at Microdyne were hand written, in black ink on photocopies using toner so they don't fade. They were stored in a locked file room, with no lights when no one was in the room, and they filled long rows of file cabinets.

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.