The electronic brooch is composed of a dual time base integrated circuit 556. It can automatically change the color of the light, colorful, and extinguish the light. Its circuit is shown in the figure.
The outputs of the two oscillators together drive a light-emitting diode 2EP301 containing two colors (red, green) with its cathode connected to a current limiting resistor R3. Since the two oscillators are independent, their oscillations are not synchronized. When IC1-a outputs a high level, LED1 emits red light; if 1C1-b outputs a low level at this time, LED2 does not emit light, and the entire luminous tube is red. Otherwise, the luminous tube is green. If the outputs of IC1-a and IC1-b are both high, the red and green are mixed, and yellow light appears from the outside. LED1, LED2 continually change the illuminating state, and its composite color changes in the UK. Since the frequencies of the two are very close, it takes more than 6 minutes (370 seconds) to see the exact same color.
The LEDs use 2EF30 series diodes with two illuminating colors. If you can't buy it for a while, you can also use two diodes that are red and green. Three wires are drawn from the small printed board, and the light-emitting tube is placed in the flower core of the transparent brooch, and the small printed circuit board is placed in the underwear pocket or hidden.
Oil-immersed Distribution Transformer, its HV level is 15kV, LV is 400V, its capacity is 2500kVA and below. Generally installed on the pole or in the distribution room, for lighting or power supply, three-phase power supply, fully sealed tank structure, to ensure the transformer safe and reliable operation.
Generator Transformer,15Kv Distribution Transformer,15Kv Oil Immersed Transformer,High Quality 1000Kva Transformer
Hangzhou Qiantang River Electric Group Co., Ltd.(QRE) , https://www.qretransformer.com