The PY801 was specifically built as an efficiency diode for television line scan and the design dates to the early 1950s. Considerable energy is fed to the line deflection coils and this has to dissipate during flyback. The efficiency diode channels this energy back to the supply rail smoothing capacitors for use on the next line scan.
This exhibit differs from our other Pinnacle PY801 in the style of the logo.
The helical heater spacer that sits between the heater and the cathode tube seen at the top. At base can be seen the heavily insulated heater wires.Also the anode plates are opened out at the ends to reveal the bright inside face. The extra surface area aids cooling.
The stitched anode.
The thin glass tube envelope is 21 mm in diameter and, excluding the B9A base pins, is 71 mm tall.
