THE GREAT MULLARD MAGIC BLOG — valve construction

Hah! what a way to finish this series on the components that make up a valve, yes, we've saved the best till last with episode 14 dealing with..... the GETTER.   Having assembled the electrode cage and mounted it into the glass envelope, the last stage in valve manufacture is to remove the air within to form a high Torr vacuum immediately before the sealing-off process.   In order to achieve this vacuum, the valve is connected to a vacuum pump and whilst being evacuated is passd through a chamber where radiant heat and an RF eddy current is applied. This double...