Improvements in or relating to electron discharge tubes for use on short waves in retarding field and similar circuits

Read the whole patent

Listed from its IP Australia record in Patent Yard's archive of Australian patents past their term. Its claims, description and drawings are in the AusPat record and on Google Patents, and the Claude kit works from them.

Why it's free to use

• Filed October 16, 1937. Even if it was granted, its term would have ended by October 16, 1958.
• A pharmaceutical extension adds at most five years, so even that would have ended by October 16, 1963.
• We check Australian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.