[volt-nuts] "*WAY* too expensive for even Keysight to redesign"

[Marv @ Home]

FYI, when a US patent expires the product is no longer patented and 
the maker cannot use the term patented, or its number, in products or 
literature.
Pequignot v. Solo Cup, 09-1547, June 2010, the Federal Circuit 
confirmed that "articles marked with expired patent numbers are 
falsely marked."   The case also discusses the use of the term patented.

Speaking of the 34401a, it was extensively redesigned as the 34461a 
and a few variants of it.  You can use it as a case study of what 
needs to be done to redesign a defacto standard.


At 07:02 PM 5/17/2015, wrote:
>"I would think that a lot of the patents would be running out soon as if
>that would make any difference."
>
>Here are some patents related to the HP3458A.
>It looks like all of these patents have expired.
>A new instrument based on these concepts and schematics can be marked,
>"Protected by the following Patents".
>US4357600
>US4951053
>US5148171
>US5689260
>etc ...
>
>
>I do not own a HP3458A, but I admire the instrument and the people that
>made it.
>The best meter I own is a HP34401A.
>It is good enough for the measurements I usually make.
>
>_______________________________________________