[volt-nuts] What made a HP3458A so expensive

Poul-Henning Kamp phk at phk.freebsd.dk
Sun Jan 19 04:44:47 EST 2014

In message <52DB4299.2080209 at erols.com>, Chuck Harris writes:

>Of course you would need to calibrate a JJ standard.  If you recall,
>the JJ works by being cooled to some LN2 like temperature, and then
>being fed with a microwave frequency that is part of the standard's
>definition.  If the temperature is wrong, or the frequency is wrong,

Actually that's not really true.

The temperature has no effect on the output, as long as it is low
enough to ensure superconductivity, and if it isn't, you get no

The frequency has to be right, and since it is typically way up
in microwave territory, 75 GHz or thereabout, that is somewhat
finicky stuff.

It's not quite the plug&play of a HP5071A, but it isn't that far
from it.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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Never attribute to malice what can adequately be explained by incompetence.

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