[time-nuts] Re: HP105B

[Bob kb8tq]

Hi

If you look at the original 105, it is a *very* different beast than the 
“final” version. They look similar (but not identical) from the outside.
The insides changed multiple times over the years.

Bob

> On Jan 18, 2022, at 9:41 AM, Louis Taber <ltaber at gmail.com> wrote:
> 
> Thanks for the HP history lesson!
> 
> I find it all pretty impressive.  I guess I have always thought great
> things about the instrumentation side of HP anyway.  Their engineering has
> always been great.  But, maintaining not only parts inventory, production
> capability for any product that has lasted over decades in the fast moving
> world of electronics is amazing to me.
> 
> I do wonder how much the product changed internally.  It has been a long
> time since anyone has used as much point-to-point wiring as was common with
> tube circuitry.
> 
> On Mon, Jan 17, 2022 at 8:31 AM Tom Van Baak <tvb at leapsecond.com> wrote:
> 
>> Louis,
>> 
>> Keep an eye on the 5071A. It was introduced in 1992; now 30 years old,
>> still in full production, showing no signs of being retired. Same
>> product number, same instrument, same parts, same manual. It also
>> survived corporate name changes: hp -> Agilent -> Symmetricom ->
>> Microsemi -> Microchip. So give it a few more years and it will beat
>> your 33 year hp 105B number.
>> 
>> It's maybe cheating to allow all the variations in the evolution of the
>> original 200A audio oscillator, as Magnus mentions. In that case you may
>> also allow the evolution of the original 5060A cesium standard: hp 5060A
>> -> 5061A -> 5061B -> 5071A. The 5060 came out in 1964, so that's 58
>> years, and counting.
>> 
>> If you're playing product history games also look at the hp 100 -> 101
>> -> 103 -> 104 -> 106 -> 107 -> 105 quartz oscillators. That covers 1943
>> (100A) to 2000 (105B), also 58 years.
>> 
>> /tvb
>> 
>> 
>> On 1/16/2022 1:18 PM, Louis Taber wrote:
>>> The HP 105B is in the HP catalogs for a 33 year period, 1968 through
>>> 2000.  That is a 33 year run.  Is this an HP/Agilent/Keysight record?
>> 
>> On 1/16/2022 2:25 PM, Magnus Danielson via time-nuts wrote:
>>> No, not for HP. The HP200A through D products where separate products
>>> for 8 years, then the 200A and 200B was merged to the 200AB and the
>>> 200C and 200D merged into 200CD that was running for 37 years,
>>> totaling in 45 years of continuous production.
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