Hi Fred,
Buzz and I have been in communications for quite some time now over various issues including his GQ, and have had discussions about modifying his detector to accomodate a DD coil.
One of the reasons for the conversion has to do with some hotrocks Buzz ran into where he hunts for nuggets. These hotrocks sound off quite strong when a mono coil is used. Some time back, Buzz sent me some of these rocks so I could experiment with them. I did and when I used a DD coil, the rocks generated a totally different reponse and were generally quite easy to distinguish. This made the DD coil conversion more attractive.
Well, recently, Buzz decided to tackle the project of converting his PI by himslef so it would accept ML compatible DD coils, and I assisted him via email.
Normally, I do not build coils for other people because my PI is set up so much different than a typical GQ which makes getting the correct damping extremely difficult. However, because Buzz and I have had so many discussions, I agreed to try to build one for him. Fortunately, all worked out ok.
I am looking forward to Buzz getting time to use the DD in the field so he can discuss the advantages or limitations of the DD on his GQ. The more people using them, the more discussions there will be, so a larger knowledge base will be available for those who want to know more. Stated a little differently, the more people trying the DD, the more people will be able to answer questions about them.
Reg