[Prev][Next][Index][Thread]

RE: NEW DISCHARGER



 * Original msg to: Esondrmn-at-aol-dot-com

Quoting Ed Sonderman:
 
> ES> How can I drive the resonate frequency down below the       
> ES> quarter wave frequency of the secondary?  
 
> RQ> You lost me here. Are you referring to the tank circuit     
> RQ> oscillating frequency?

 ES> What I am trying to say is the calculated quarter wave       
 ES> frequency of the secondary (determined by the wire length)   
 ES> is 154 khz.  This should be where maximum voltage is         
 ES> produced at the top of the coil.  With two tank caps in      
 ES> parallel and the primary tapped at 14 turns, I calculate a
 ES> frequency of 93khz.  I think you are trying to tell me that  
 ES> the secondary has a natural resonate frequency of it's own   
 ES> and we can change it by adding larger and larger dischargers 
 ES> - and that the quarter wave calculations have nothing to do  
 ES> with it  -- did I get it?          Ed Sonderman

You have got it! A bare secondary coil, that is a coil with no
discharger or isotropic capacitance on the air terminal has a
"base" or "natural" resonate frequency. This frequency should be
determined as accurately as possible and then recorded. 

The secondary coil can then be made to resonate at lower
frequencies by adding a discharger. The larger the discharger
that is placed on the coil, the lower the resonate frequency of
the coil gets. Thus it is possible to make a secondary coil
resonate at much lower frequencies than those calculated by the
wire length alone. I do not know of any way to make a coil
resonate at a higher frequency without removing wire. 

It follows that by lowering the resonate frequency of the
secondary coil, it is then possible to add more capacitance 
(and power) into the tank circuit without losing the ability to
match the tank circuit/secondary tune. If the discharger that is
added to the secondary coil is large enough, then not only can
you add capacitance to the tank circuit, but you can also add
turns to the primary coil.

What this means is that a simple discharger change on the
secondary opens the door to more input power (larger tank circuit
capacitance), and then allows more efficient use of this input
power (more primary inductance).  

Richard Quick


... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12