A magnetic field effect transconductor device (M-FET) capable of carrying a modulated current when receiving an external magnetic field includes at least a ferromagnetic layer and a non-ferromagnetic layer disposed on the ferromagnetic layer; the non-ferromagnetic layer has a first skin depth of the current and a first thickness smaller than the first skin depth; and the ferromagnetic layer has a second skin depth of the current and a second thickness smaller than the second skin depth. Applying an external DC magnetic field along the longitudinal axis of the device and an AC EM wave propagating in the same direction as the DC field, the M-FET demonstrates frequency dependent current switching device. A method for making the transconductor includes depositing a photoresist over transconductors and patterning the photoresist, or depositing transconductors over a patterned photoresist and performing a lift off process.