Is FGM really fluxgate or is it variable permeability

[Atul Asthana]

From the ckt diagram of FGM (XRAYed and then guessed elsewhere on this forum) and the variable frequency out put makes me think that it is probably a variable permeability sensor, described elsewhere by Don Lancaster http://www.tinaja.com/glib/muse104.pdf

Using a capacitor in the osc circuit is likely to make FGM temperature sensitive.

Kindly opine.

[olsteffe]

It is probably a variant of the RTD fluxgate. A pure inductive sensor would just need one winding as it is also said in the hack. So a kind of squegging / relaxation fluxgate.
Sincerely
olsteffe

[mrkhrdr]

It is probably a variant of the RTD fluxgate. A pure inductive sensor would just need one winding as it is also said in the hack. So a kind of squegging / relaxation fluxgate.
Sincerely
olsteffe

olsteffe- I don't know what an "RTD" fluxgate is. The only term I know that RTD abbreviates is "Resistive Thermal Device", the platinum resistivity based thermometer. Could you enlighten us, or provide a link that would?

[Qiaozhi]

olsteffe- I don't know what an "RTD" fluxgate is. The only term I know that RTD abbreviates is "Resistive Thermal Device", the platinum resistivity based thermometer. Could you enlighten us, or provide a link that would?

You might not get an answer, as the post you're replying to is 4 years old; and I've just checked that Olsteffe hasn't been active on the Geotech forums for 18 months.