[TowerTalk] Shunt Feeding a Vertical

[john at kk9a.com]

Nice video Steve - great job!  I have never shunt fed a tower but I  
understood what you meant by 50 ohm point.  I am curious what happens  
if the tower is short, wouldn't an inductor cancel out the tower's  
capacitance?

John KK9A



VE6WZ_Steve ve6wz wrote:

Joe….yes, I agree.

The “tap-point” itself is not 50 Ohms, but is transformed to 50 Ohms  
at the end of the shunt wire. After the inductive reactance is  
canceled out by the series capacitor, the system is at resonance with  
zero reactance and 50 Ohms pure resistance.

The term “50 Ohm point” does indeed refer to the point at which we  
measure 50 Ohm Real R at the shunt wire at the feed-point.
Moving the shunt wire higher on the tower will increase the R, moving  
it lower will lower the R.


Steve, ve6wz