difference between coils

been away for some time can someone tell me the difference between the 11 inch DD and mono coils of the old SD detector ...would be much apeciated

G'day Heavyhanded. Welcome to the forum.

You'll have to be more specific on what exactly you mean by differences,in other words what differences are you referring to,and how far back or what model of the old SD Series are you referring to.From your question,all I can come up with at the moment,is that one coil (DD version) will show to be far more quieter in operation over mineralized ground than the mono coil and the mono version will show to be much more sensitive on the same size target,hence showing slightly greater depth (on the same size target) than its equivalent size DD brother.

Cheers kon61.