The type 80 was the landmark full-wave rectifier and (we think) the first mass-produced rectifier to use oxide-coated tape filaments. This exhibit from Philco has the older balloon envelope and probably was made earlier than our other Type 80 exhibits.
The maximum reservoir capacitor is 32 µF and the minimum series resistance, to limit current, is 30 Ohms.
The standard anode shape. Folded and stitched to the support.
Here the filament tension springs can be seen together with the glass rod central insulator.
The filaments are oxide coated ribbons in an inverted V formation.
Top view showing the fixings of the anodes and tensions springs to the central glass rod. Later forms of construction use mica supports as can be seen here.
The balloon envelope is 54 mm in diameter and, excluding the UX4 base pins, is 116 mm tall.
References: Data-sheet, private communication, 1040 & 1043. Type 80 was first introduced in 1936. See also1936 adverts.
