[Boatanchors] Vacuum tube op-amps

[J. Forster]

David Ross wrote:

> BAfolks -
>
>   Some links to interesting articles on vacuum tube op-amps here:
> http://www.national.com/rap/vacuumtubes.html
>
>

Interesting. My late graduate thesis advisor, Henry M. Paynter, wrote a book for
Philbrick called 'A Palimpsest on Operational Amplifiers' which is the absolute
standard on their use. He also designed some of the Philbrick plug-in models and
included a 'gimmick' capacitor which was destroyed if you opened the case, to
prevent reverse engineering.

-John