[ARC5] Mils Specs On Line

[Bruce Long]

Back in the 80's I worked briefly for a company that made custom microwave sources.  A good portion of our orders where for signal sources used to tune up , test or adjust military radar/missile equipment.  We regularly received temperature specifications of -50 to +85 degrees C for equipment to be used in a test lab.  If the electronics repair bay on an aircraft carrier is at -50 or +85C I strongly doubt people would be thinking about signal source temp stability.

Oh and there was a classified Mil satellite program I worked on that ended up with a large percentage of counterfeit 6-32 mil spec, space grade machine screws.  Turns out somebody bought an old freighter, fitted out the hold with screw making machinery, would sale to China, buy a load of scrap grade steel road and use the long trip to the US west coast having the otherwise idel sailors operate the screw making equipment.  They forged the Mil spec certification paperwork and sold the junk as super premium mil space space grade.  The distribute, on they determined they got the required paperwork with the purchase just dumped these screws into the bins with authentic high grade screws. 

We found this out when our component when to pieces during qualification vibration testing despite the screws having a 200 to 1 strength safety factor.  On the same job the newly put in buisness quality testing lab blew out all 4 dozen of our $100 each mil spec- space grade NPN and FET small signal transistors  2N2222 and the mil equivalent of a 2n3819 fet.

The transistor mil spec was written for germanium transistors and allowed as much as 1 microamp leakage current.

The testing lab increased the reverse voltage until the leakage current reached the test limit.

So we spent the equivalent of over $1000 per transistor in quality up rating and testing and every single transistor was deader than a doornail.   I spent a confusing day in the clean room trying to figure out how every single transistor could be acting as an open circuit.   They just could not be all bad.  Even Radio shack transistors would not all be that bad.  No way they could all be bad.  Just no way

I had to pry out a copy of the IEEE-488 automated testing equipment software control code to find out what the testing lab actually did.

there is a lot more to this tale of woe but I got to get back to work.


On Monday, March 31, 2014 12:15 PM, Robert Eleazer <releazer at earthlink.net> wrote:
 
I understand that the Milspec for tortillas originally ran to 20 pages.  I think they revised it and got it shortened.

I recall hearing that the cascading effect of milspecs referencing each other led to a piece of GSE, intended for use on the deck of an aircraft carrier, being required to operate at 30,000 ft.  

The one that caught my eye in the list one day was "Diaphragm, Vaginal Female."  I never looked that one up but it led to me looking for a mispec on bras.  I never found one; I was curious about the vibration test requirements.

Thanks again for the links!

Wayne

    
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