Topband: Reactance

[David Cole]

I have an 80m vertical 62ft 6in high tuned against 120 -  70 foot radials - I am trying to achieve a base impedance of 25 j0.

The current configuration shows 26 j18 - I have put a capacitance of 38pf from the base of the vertical to the radial system and this gives me 25 j15.

How do I get rid of the imaginary reactance of j15 

The reason why this is critical is that I need 100ohms j0 at the end of a 90 degree length of 50 ohm coax, any small variation away from 0j at the input makes a large change in the required 100 j0

 
Dave RCQ