[oobovril]

I notice that some valves have dropped out from the later editions of the AVO valve data books. I have an 3A5 valve that appears in the late 1950's valve data book but has disappeared by the time the much later 23rd Edition data book was issued. I assume though that the valve setup data, back from the late 1950's edition, can still be used today, or was there a problem testing some of these valves hence their removal from the later editions of the data books.