January 2013 During an antenna capacity top load repair and upgrade a short while ago I found that I needed to reduce the number of turns on the lower coil (variometer) to get a matched and resonant tuning point on the 500 kHz band. By fitting an additional connector (black) lower down the coil it was easy to achieve this. With the introduction on 1st January 2013 of the new MF band allocation at a lower frequency of 472 to 479 kHz, I am now able to use the previous (red) connection to obtain resonant tuning and matching, see left.
September 2013 This next change (experiment) in the antenna hardware is more of a request (demand) from my XYL. I think that she has for too long put up with the Starlings perching on my antennas and “pooping” on the washing hanging on the line in our small back garden. So the idea is to change the arrangement of the hardware so as to reduce the impact of Starling droppings. This will mean reducing the size of the LF vertical top load structure as this is the main contender of the problem. I will be removing as much of the horizontal structure as possible. The project could allow me to make the vertical top section a little longer as the existing structure only just fits between the mast and the house when the mast is tilted horizontal. In its new position on the mast it will miss the house by a small margin being in line with the drive.
November 2013 I will be making a 250mm diameter anti-corona skeleton sphere from 2mm copper wire and mount this on the top of a short length of 40mm PVCu waste pipe. Immediately below this is to be an elevated inductor wound on a 100mm diameter clear plastic tube. The coil former is supported by the length of 40mm PVCu waste pipe using nylon bolts. This whole assembly is fitted on the end of a 2 meter length of aluminium tube and fixed to the top of the fibreglass pole with stainless steel bolts and allowing a connection to this point at the bottom of the tube. From here the vertical feeder will be helically wound down the original 3 metre fibreglass pole and mounted on a heavy duty thick walled aluminium stand off arm to position it away from the main mast.