It's been 30+ years since I watched that and some of the other early Garrett movies. Can't see this without a link. John, if you would post the link to cut-and-paste it would help.
Thanks.
Monte
PS: That TR-Disc. was the newer version from about '77 I have the former Master Hunter TR-Disc. bought brand new in '76 hanging on my den wall. I use it now and then for memory sake, but mainly in my seminar's to show folks what we had .... and what performance we lost on the way to get to where we are today. The main difference is my TR-Disc. unit has the Double-D or what they then referred to as Wide-Scan search coils.