[ARC5] Way OT -- SX-28

[Hubert Miller]

>The lowered filament voltage was common on both diode detectors and especially diodes used as series noise clippers. 
The idea was to reduce hum from the electron cloud of the cathode (I am drawing blanks today, there is a proper name for this effect). 

Is this the "space charge", which is the same phenomenon which makes "contact bias" possible in such tubes as 6AV6 ?
-Hue Miller