Jones Beene wrote: > > Frederick, > > Although the JNL specs show otherwise, would you guess that his > cathode is thoriated ? Even if it was, it would not have shown up > in the radiation tests, most likely. > If he didn't modify the tube much the filament could be thoriated.
BTW: The thoriated filament emits about 1.0E5 times as much as a pure W filament at any given temperature and at 2000 K -1324 watts could be emitting way over 8 amperes of electrons, even though the power is greater than the 750 watt vacuum rating of the tube. (the hydrogen cooling and electron emission is holding the filament at the lower temperature). The "missing" ~ 24% power could be because the electrons are getting to ground though the tube wall, thus it's also acting as a thermionic converter. ? This would make the filament resistance ~ 0.075 ohms at 2700 K and 0.008 ohms at 300 K. At 1700 K ~ 0.043 ohms, at 2000 K ~ 0.052 ohms and ~ 0.058 ohms at 2200 K. For 1324 watts at 2000 K, I = ~160 amps V = ~ 8.33 volts etc (the battery can handle this). Frederick. > > Jones
