DD Eclipse Coil - Need Advise

[Steve Herschbach]

The V3i coils had to be made to a higher tolerance, so all V rated coils will work on the DFX M6 MXT VX3 V3i etc. but older coils for those machines that are not V rated may not work on the VX3 and V3i at high gain levels. From the VX3 User Manual:

The VX3  uses induction-balanced loops which rely on a “null” between the transmit coil and the receive coil. The quality of the null may determine the point at which the detector overloads, especially when running high Rx Gain settings. Null quality varies loop-to-loop, so some loops may overload at lower gain than others. In other words the quality of the loop null can also push the input amplifier toward overload. White’s V-compatible loops are designed to minimize null limitations, but third-party loops typically have wide variances in the quality of the null which can require a lower Rx Gain.

Again, V rated coils are just made to better tolerances, it's the older coils or aftermarket coils that may experience overload at high gain if used on the VX3 or V3i. Even then they will probably work - you'll just have to back the sensitivity down. Models other than the VX3 and V3/V3i it does not matter.