Topband: T-vertical again

[Steve Flood]

I have my T-vertical up now.  70 foot topwire, 71.5 foot vertical wire, and 38 radials on the ground.

Last night I could here the Europeans on the vertical and zilch on the dipole. Very exciting but no luck working them.  I have couple things left to do yet...

My feedpoint Z:

1.800 MHz  24-j25
1.825 MHz  25 - j14
1.846 MHz  26 + j0
1.870 MHz  27 + j9

I am thinking of adding a coil at the top of the vertical wire to cancel the capacitive reactance at around 1.825 MHz.  Is there a way to calculate what the reactance is at the top of the vertical wire based on the feedpoint reactance? (..and thus determine what size coil I need up there)

Also, it looks like a 2:1 UNUN is in order at the feedpoint as well.

Comments or suggestions?

Steve
KK7UV