[Boatanchors] Suppressor grid modulation

[mac]

The 813 being a beam tetrode type of tube, not a power pentode, does  
not have a suppressor grid as such even though many base diagrams may  
appear to show one.  Pin 5 on the base of an 813 goes to the beam  
forming elements in the tube, not to a "suppressor" grid.  See any  
50's or 60's ARRL handbook for a more on the subject.

Dennis D. W7QHO
Glendale, CA



On Jan 27, 2010, at 7:31 AM, Paul Baldock wrote:

> Could someone explain to me what characteristic makes one tube good
> for Suppressor Grid Modulation like the 803 and another tube not
> suitable like the 813?