Tdi coils on GPX?

[bklein]

Ive read that TDI coils should not be used on GPX machines but GPX coils can be used on the TDI.
Doesnt make sense to me, can someone explain?
I have a GP Extreme, not GPX. TDI Beach Hog seems to work on it. Curious to try the surf DF coil next.
But don?t care to blow out the front end as it was a bxxxx to fix.

[Carl-NC]

They'll work, but have higher resistance so peak current is less.

[bklein]

I tried a variety of coils on the gp extreme. The df coil and beachhog (for tdi) saturated but performed better than if put on a df. Made me wonder about coil saturation - is it a waste to try and drive a coil into saturation? Or would it maybe be a case where tx doesn’t benefit but due to design the rx side may?

[bklein]

GP Extreme and Whites DF with TDI Beach Hog, DF, and Minelab 11" Mono Commander coils

Here are some photos of voltage/current with various detector/coil combinations. You can see the saturation of the DF and Beach Hog coils on the GP Extreme. Even so, the depth was better than they did on the DF.

[Orbit]

Here are some photos of voltage/current with various detector/coil combinations. You can see the saturation of the DF and Beach Hog coils on the GP Extreme. Even so, the depth was better than they did on the DF.

A lot of noise has an oscilloscope but everything is reasonable ...

[ionut_mtb]

Can someone tell me the measurements of the gpx coil and lower shaft? I’m referring at distance between the “ears” (inside), rubber spacers thickness and diameter, shaft size. I want to make 3d drawing for my printer. Thanks

[Altra]

Approximately 24mm inside the ears, I measured a Commander 11" DD and an 8" mono

[ionut_mtb]

Approximately 24mm inside the ears, I measured a Commander 11" DD and an 8" mono

Thanks, looks like excalibur lower shaft is the same. This is what i made.

[Altra]

Nice Work! Yes most of the Minelab coils use the same width between the ears.