[Test-Equipment] HP serial numbers?

[Stan]

Lars E Pettersson wrote:
> 
> On http://www.hpmuseum.org/collect.htm#numbers I found an explanation on
> serial numbers for HP calculators. They stated:
> 
> YYWWC#####
> 
> YY = number of years since 1960
> WW = week number that year
> C = country code
> ##### = serial number that year and week
> 
> After 1996 they use
> 
> CCYWW#####
> 
> CC = country code
> Y = last digit of year
> the other as before
> 
> Is this the way they also numbered test equipment. I checked my HP5328 and
> HP8640 and they fitted nicely into the first version, manufactured 1978,
> and 1979 respectively.
> 
> How precise are the dates?
> 
> /Lars
> 
> --
> Lars E Pettersson, SM6RPZ
> Gothenburg, SWEDEN
> sm6rpz@home.se
> 
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Hi Lars,

This may be more than you wanted to know!

I can't speak for the calculator side of things, but with HP/Agilent
test equipment, the four digit serial number prefix that represents the
year and week of manufacture is only an approximation. In my experience,
the prefix assigned to the *first* batch of a particular model of
instrument is a good indication of the initial date of manufacture, as
confirmed by the first year that particular model appears in the
HP/Agilent catalog.

As production continues, however, the prefix is changed only when there
is a significant revision to the product design. Low volume production
instruments seem to have only a few (or sometimes only one) prefix
assigned, but high volume production, or highly revised instruments may
have many (just look at the 8640B or the 5245L for two particularly good
examples). Reading the title pages of the operating and service manuals,
it is clear that there is a specific and unique set of serial number
prefixes assigned to a particular model of instrument, yet we must also
assume that any particular model is in continual production during its
lifetime. Also, in any given week, HP/Agilent was/is manufacturing
literally hundreds of different models of instruments. If they tried to
change the prefix every week in order to represent the exact date of
manufacture, it would not only be very difficult and potentially
confusing, but if there was a week in which HP/Agilent produced more
than 100,000 items, they would run out of serial numbers.

Another point of interest: if you were to call Agilent today and give
them just a serial number, they could tell you to what model instrument
it is assigned, the exact date of manufacture, the warranty expiration
date, and any options installed at the time of manufacture. So clearly
they track all of these things a lot more precisely than we mere mortals
can determine by reading a serial number plate.

Regards,
Stan