[time-nuts] Re: measuring tiny devices

[Richard (Rick) Karlquist]

On 5/26/2022 10:24 AM, Lux, Jim wrote:
>
> 
> https://www.mwrf.com/technologies/test-measurement/article/21849791/copper-mountain-technologies-make-accurate-impedance-measurements-using-a-vna 
> 
> 
> describes the various approaches

I don't know how long these methods have been in use, but I 
independently (re)-invented them around 40 years ago.  At the
time I was working for HP and attempted unsuccessfully to interest 
various HP business units in publishing this as an ap note, as
copper mountain has.  Meanwhile I taught them to numerous
hams, clients, and HP engineers, etc. Fast forward now to 2022 and 
nearly everyone knows about them.

As useful as they are, they have serious limitations:

1.  The high-Z workaround requires the DUT to be floating.
2.  The low-Z workaround requires the DUT to be grounded.

Can anyone suggest workarounds for the workarounds?

Rick N6RK