Not trying to clog up the forum with ebay item(s), but this looks like a hard-to-find item someone here might want: ebay.com/itm/18-Cannon-Coil-For-Whites-TDI-Metal-Detector-/2 Never seen one of these myself and have never heard of this company (if 'Cannon' is actually a company name -- maybe it's not).  Says 17 microsecond or longer delay is recommended, which takes it out of my wheelhouse since my TDI/SPP is locked at 10 us.