WD8DAS SB-230 Amplifier Tube Retrofit Project

Air-cooled Russian GI-7B triode replaces the conduction-cooled 8873.
Heatsink removed, plenty of vent holes all around. and a small muffin fan running at reduced voltage.

Top view.

Under the RF chassis.

High voltage section.

Filament and 12vdc power supplies.

Rear view.

One miniature combination Russian phrase book and datasheet

One schematic diagram, three pair of nylon stockings