03-24-2016, 06:33 AM
Quick update, the Columbus 7B1 battery set (http://www.radiomuseum.org/r/columbus_7b1.html) from that era has a sensitive/economy switch in the schematic... its possible other sets did too. I'm not sure how many valves this had now... I'll know more when I can start pulling things apart... which I shouldn't do right now... so I probably will.
There are no personal problems that can't be overcome with the liberal application of high explosives
