Re: Tube coils

["Herwig Roscher" <herwig.roscher-at-xxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

Stephen Carpenter wrote to the list:
>why not try a tube coil.

Stephen,

Try it. It's a very interesting matter.

> 1) What is a "grid coil"? 
The grid coil feeds back a part of the plate voltage and 
starts/maintains the oscillation if it was phased correctly.

> 2) Are both the "grid coil" and "primary" coupled with the 
secondary? 
Yes. Usually the grid coil is located on the form of the primary coil. 
You would like to provide for a variable distance between the two 
coils in order to adjust it for the best coupling. Please think of the 
large voltage difference between the two coils and chose a 
sufficient minimum distance.

Good luck!

Herwig