15-04-2012, 09:26 PM
Just come off the phone from Dennis and (Dennis being Dennis) he chucked a nice sized elelctronic grenade in my direction. The early radios with 2 volt heaters were battery powered and the internal resistance of the batteries would limit the amount of cold amps being drawn by the valves. As he quite rightly pointed out, a modern equivalent would provide full amps from turning on and it is possible that this could limit the life of the 2 volt heaters, quite a good point and a question to which I'm stumped.
