Has anyone ever considered the utility of switches that double as parametric pumps?https://sci-hub.st/10.1109/T-AIEE.1951.5060643^That article is in regard to a device called the magnetic cross valve. They were used in the early telephone days to take low frequency 60hz signals and transform them to a higher frequency. They were also used in things like school bell ringers (pic rel).The concepts behind these types of devices are similar to those that gave us things like the Magnetic Amplifier.The way the magnetic cross valve works is not via direct magnetic coupling. The two magnetic coils do not couple with each other because they are at a 90 degree offset...instead the two coils share a common ferromagnetic (laminated iron) core. When the first coil is energized, it's magnetic field saturates the iron core...the core becomes magnetic and because it's shared by the second coil, it acts similar to a waveguide and "bends" the magnetic field lines through the turns of the second coil. The iron core acts as a non-linear medium for magnetic field lines. When the core becomes entirely saturated, it loses it's permeability and acts as a "break" or switch for the second coil which then de-energizes. Because of this, these devices have the ability to multiply the frequency of the second coil based on the permeability of the iron core.
>>17004410Because of this, the iron core acts as a non-linear, parametric pump of the second coil. In this configuration, it is not necessarily an "amplifier", but under the right conditions it seems like it should be.The non-linear iron core creates a hysteresis loop that when plotted out creates Lissajous figures.Given this, there should be a way to turn a switching system (the iron core) into an actual amplifier. The first coil is parametrically pumping the saturation state of the shared iron atomic lattice.Things like memristors also exhibit Lissajous hysteresis loops.
