Re: Tube Impedance Matching

["Herwig Roscher" <herwig.roscher-at-gmx.de> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Ross Overstreet wrote to the list:

> that you have to match the input and output Z of the tube, but I'm 
> not really sure how to do this in the VTTC. 

Ross,

I've got the same problem. IMO the dynamic output Z of the tube 
has to be adjusted to the the Z of the "brush". Terry (thanks, Terry!) 
has found it to be about 20 kOhms + (3 kOhms/100 W delivered) in 
series with 0.58 pF + (0.07 pF/100 W delivered). As the tank circuit 
and the secondary circuit are parallel resonant circuits, they should 
have an impedance much higher than the output Z of the tube and 
the Z of the discharge as well. So, matching should be a question 
of the TC transformation ratio.

Please correct me, if my assumptions are wrong.

Regards,

Herwig