LF,   Acting on advice I have installed a whip aerial (probe) on top of a mast at the boundary of my property. This is in order to monitor my VLF transmissions and to provide a reference level for any system improvements.   I noticed that the probe's pick-up voltage is directly proportional to my PA's supply current. Assuming that the PA efficiency doesn't change drastically with current then would I be correct in assuming that the probe's voltage is directly proportional to the radiated power?   I was expecting a square law relationship . .   73 Chris G3XIZ