I have had quite a bit of idle time since this all arose, I began to look at a number of things.
Firstly, I discovered it is NOT a C phase lightening arrester, but a THREE phase lightening arrester. Read up a bit to understand what this is and I think this has given me some perspective :http://en.wikipedia.org/wiki/Three-phase_electric_powerhttp://en.wikipedia.org/wiki/Lightning_arrester
Am still confused if it is arrestOr or arrestEr !
Went to the back of the house and took this picture of the pole with the culprit arrester/arrestor and one of these ceramic/polymer objects, I assume is my problem :http://i1098.photobucket.com/albums/g372/N4DOV/lighteningarrestors_zpsb5bc06fe.jpg
Well I also made of video of site and sound of the noise, together with how my 2 great radios handle THIS noise via their Noise Blanker capabilities, in this instance. I apologise for the shaky nature of the video but as soon as youtube have stabilised the video, I will repost the link.http://www.youtube.com/watch?v=Si26cABHa9s
Again thanks to all and will update if problem resolved.
73's David N4DOV.