Very much On Topic: Integrated Vacuum Tubes

[Tony Duell]

> I have a few 500 series plug-ins with nuvistors, and have found them to be

FWIW, late versions of the 1A1 (dual-trace 50MHz-ish plugin) have a pair 
of nuvistors on the output PCB. Old versions, like mine, have those 2, 
and anothter 2 on each of the range switches for the input amplifer. A 
total of 6 therefore.

-tony