Demons can smell like sulfur, roses, cologne...anything! They can also appear as: an angel of light, a dead person or child, a spirit guide, a healing spirit (reiki), an alien, a fairy, a dwarf, a spirit animal etc! We can't safely discern them! The safest thing to do, is let Jesus and his angels protect us.
The recommendation is therefore that the stimulation should be applied with a 2500Hz carrier medium frequency sinusoidal alternating current, burst at 50 Hz (10ms ON: 10ms OFF) at a maximum tolerable level.
The cutoff frequency is defined as the frequency at which the ratio of the (input/output) has a magnitude of 0.707. When this magnitude is changed to decibels â3dB mostly referred to as the 3dB down point. The cutoff frequency is characteristic of filtering devices, such as RC circuits.