[600MRG] RF Ammeter Placement and Antenna Feedpoint Location - Extra Info

[Andy - KU4XR]

Off list replies asked, so I will add this info .. The Loading Coil is a Tappable Tank Coil.. I ground the end at the TX,
and tap UP to match the TX to 50 ohms .. I tap DOWN from the top to find the point where Minimum SWR and
Maximum RF Current happens at the same time .. The Coil is in Series with the Antenna / TX circuit .. 
No Shunt " C " .. I finally tested the RF Ammeter with my Dummy Load .. I measured it with a meter at 51 ohms..
I connected it to the TX and the current read .625 amps ( squared = .390 ) - 20 watts / .390 ( I^2 ) = 51.282 ohms.
At least I feel more confident that the RF Ammeter is trustable .. 

Andy - KU4XR
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Hi all:

I need to ask a couple of questions so I will know whether I am thinking correctly or not.

Question - 1: Where should an RF Ammeter be placed in the circuit ? My setup is: TX - Loading Coil - Inverted " L "
Is the correct location for the meter on the TX side, or the Antenna side of the Loading Coil ? ( Coil is inside the shack ).

Question - 2 : In my setup; What is the " Antenna Feedpoint " location ? TX end of the coil, or the Antenna end ?

Here is why I ask. Today I ran across a document for an MFJ Balanced Line Dual Current Meter .. In the document,
I read " How to calculate Antenna Feedpoint Impedance " .. It stated; " Divide applied power by square of Feedpoint Current. "
Curiousity took over and I came up with these readings .. TX power is 20 watts .. Using ammeter readings as they are ..
Antenna is - 65 feet of RG-59, shorted at both ends - connected to top of coil located in the shack - running a few feet
across the wall to the window, out to the mast at 30 feet AGL,  and a total length of 961 feet of Top Loading..
Top Loading is 4 legs - fanned out - connected together with a perimeter wire to make up the total length of the Top Loading..

Meter on antenna side of coil - 1.2 amps - squared is 1.44 amps ; 20 / 1.44 = 13.888 Ohms

Meter on the TX side of coil - .6 amps - squared is .36 amps ; 20 / .36 = 55.555 Ohms

The PA FET gets hot during TX - I have been told that my antenna is " close enough for the TX to operate into , but ,
not resonant enough to present a 50 ohm - non-reactive load  to the TX. ". Without test equipment; can I get it closer ?
I am not up to speed on antennas at MF, nor the heavy math for calculations..
My " assumption " is that my antenna is Capacitively Reactive ( have no instrument to measure it to find out )..
To obtain the readings I have - minimum SWR at maximum RF Current - I need 30 microHenries of coil Inductance..

Question - 3 : Could I possibly need an amount of Series Capacitance ( since the total length is 1/2 wave at 456 KHz ).
Can that Capacitance be calculated ?

The antenna is " not there yet " , and I hope I am not chasing - skinny bunnies around the bushes ..

Thanks for reading, and any possible replies .. critique what is needed ( I know the radiating stuff should be outside ),
And post it to the list for the benefit of others .. Who knows; someone might learn something from my escapade's ..

73: Andy - KU4XR