[R-390] R-392 help

[Flowertime01 at wmconnect.com]

John Bunting wrote,

By the way, has anyone else noticed how Collins slips these little 
things into their designs.  Like the separate B+ pin on the Power 
connector of the R-392?  One would 'almost' think that somebody was 
thinking about making the R-392 capable of running AC for the filaments 
and separate DC B+ for fixed operation.  Has anybody tried that? 

-------------
John,

My late 1920s 6 volt Gurnow has separate conductors for the filaments and the 
B+ lines. In the military models you could run an extra "line filter" on the 
B+ line for less generator noise when the engine was running. The filaments 
were by the 1950s isolated from the cathodes so some noise on the filament 
voltage line was "OK".

Some time the good battery was run on the filaments to give good current and 
the weak battery was run on the plate line that usually draws less total 
current.

There are lots of reasons to support multiple power conductors between the 
power source and load.

Roger KC6TRU