[Premium-Rx] Wellbrook Loop antennas

[Mac]

Question about using my Wellbrook antenna,  does anyone know the DC 
input polarity for the amplifier box, This is the box that takes the 
input signal directly from the actual loop does the amplifier magic then 
sends the signal on to the receiver's typically 50 ohm antenna input.

For reasons that shall not be explained I have noticed the power supply 
[wall wart] and i doubt it is the original supplied unit Wellbrook sent 
or included, has reverse polarity wherein the center pin is - Negative 
and the body is + positive.

While Wellbrook is British made I am just unsure if the amplifier box is 
indeed reverse input from what is now the more industry standard of 
center pin positive and body negative and I can find no documentation 
detailing the desired input, so I am asking the group for experience or 
factual schematic..

Thank you in advance.

mac/mc  w5mc