Wayne Parham Messages: 18752 Registered: January 2001
Illuminati (33rd Degree)
You basically need to have every socket and switching logic to connect a variety of tubes in a circuit that will operate it at various levels. The tube circuit needs biasing and load resistors and a dial movement (at minimum), long-persistence CRT or D/A and A/D converter and control/capture software to display and/or record current through the tube. For a simple single point bias level, it can be done with fixed resistors but to automatically generate a load line, a sawtooth wave generator is required to "sweep" the tube. Lots of wiring in there to allow it to be configurable for any tube.
But this is not a new technology. These kinds of devices have been around for years. So I think I'd probably just buy one and consider it money well spent. It's a lot of work to build one and you'd be re-inventing the wheel.