Teach you to manually wrap the magnetic loop coil

Introduce the manual winding of the magnetic loop coil with an example:

The turns ratio is 1:5.3333. In theory, the 1.5V AC voltage can be raised to 7.99999v. The practical problem is that if you use a small magnetic ring, the inductance of 6匝 is very small, this 1.5V AC voltage. If the frequency is high, there is no problem. If it is low frequency, a large current will flow, which may damage the power supply.

This is a small product that replaces the 9V laminated battery (model 6F22) with a 5th battery inverter boost and is sold. Using the inductance of L3 to boost, due to the use of the Zener tube, the efficiency is not high. The principle of self-oscillation, the frequency is relatively high, and the peak voltage of the right coil is at least 20V, which is related to the duty cycle.