Philips - CHF Müller Kenotron

Ref. G11

The longer kenotron is a 9” (22.5 cm) high, oil immersed Philips kenotron, made in Holland, dating to the sixties or early seventies. Rated 150 kV and 1400 mA, and a filament voltage of 6.5 V. (Note the discontinuity in one of the filament strands, seen in the X-ray picture).

The shorter kenotron 7” (17.5 cm) long, in the picture top right, is a physically identical kenotron, (without the end metal parts), dating probably to the fifties, German made by CHF Müller (Philips owned). No technical information, except the yellow label showing the Müller mark and the type and the serial numbers (different from those on the Philips kenotron), and the mention “150kV”.

As from the seventies kenotrons started disappearing in favour of solid state semiconductor rectifiers. Certain manufacturers even made such replacement rectifiers in a size to fit physically the place of kenotrons in high tension generators of their make.