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previous: Richie{~}==::: Peter: Seems like they use differen... -- 9/13/2000 10:49 PM view thread

Re: Output tube Grid Resistors

9/13/2000 11:37 PM
nuke
Re: Output tube Grid Resistors
The ouput tube grid-to-ground (or bias supply in most cases) resistors are there to stabilize the tube's operation. You need a path to ground to "drain" off accumulated charges on the control grid.  
 
Different tubes require different Rg1 values. Higher quality tubes with fewer residual ions and secondary emissions will tolerate higher values than recommended in the spec sheets on the tubes.  
 
But a lot of recent production tubes aren't of the same caliber as back in the day. (early 90's tubes were often notoriously bad - the situation is generally better today).

 
Replies:
Peter S I've found alot of different values... -- 9/14/2000 1:44 AM