Garrett Groundhog

[Qiaozhi]

Please note - I have already posted this question in the Coils Forum.
Does anyone here know the internal coil configuration of the Garrett Groundhog?
This is a 1970s VLF/TR detector that was the machine for finding gold. Its frequency of operation is 15KHz.
In particular, I would like to know the inductance of the TX and RX coils, and whether the tuning capacitors are contained within the search head or on the PCB.