four tone mod?

[just lookin]

Since I know nothing about metal detector electronics or electronics, I need to ask this question, I have just bought a Older Brown box Tesoro Eldorado, and to my best knowlegde it does not have veraible tone id, is it possible to mod this old Eldorado so that it has a four tone ID? I will will gratefull for any help!
Thanks Greg

[kt315]

Greg,

I do not really why I must remind this as my English is very poor and here are much people with VERY good English so I only repeat if you are still not in course of the TONE ID subject.
Carl HAS traced Golden uMAX. what WE did see in this schematic - ID on a chip.
simple realization may be done. I do not put the schematic because big volue and this is of Carl.

anyway, happy hunting and Marry X-Mas.

[kt315]

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