30-01-2021, 03:09 PM
Hi Trevor,
Filament supply is stabilised (lab bench supply right now, but longer-term aim is to make a switch mode supply, running from batteries).
That being so, including a low-current negative rail is a comparatively minor matter.
Floating the filamentary cathodes DC-wise is definitely non-preferred, but having signal voltages on the cathodes is a distinct possibility. Winding one's own transformers and chokes gives a degree of freedom here!
Filament supply is stabilised (lab bench supply right now, but longer-term aim is to make a switch mode supply, running from batteries).
That being so, including a low-current negative rail is a comparatively minor matter.
Floating the filamentary cathodes DC-wise is definitely non-preferred, but having signal voltages on the cathodes is a distinct possibility. Winding one's own transformers and chokes gives a degree of freedom here!
