26-11-2016, 12:37 PM
I completed it, and it does work, but with the same rather erratic results that my Avo Mk1 tester produces! Different valves of the same type give different readings. It is easy to say that some are better than others, but they all have one thing in common, in one valve radio circuits, there is no audible difference in performance! It is more consistent with triodes! The more I read about valve testers, the more sceptical I become, and wonder if in many cases they were just an excuse to say that a valve was low in emission, and needed replacing. (I am talking about the 40s, 50s, and 60s now!) I have no doubt that modern versions can analyse a valve 100%, but in the end, if it works OK, that is all that matters. I will probably end up dismantling this one, and going back to my original, that tests the valves in a one-valve receiver circuit, whilst providing monitoring for anode current.
Bob
Bob
