When the LS3404 melody chip U1 is activated, "hold" S1 is pressed, SCRI is turned on and the telephone line is held through T1, R1 and LED1. The voltage is used to activate the melody chip through R1 and LED1. Q1 and Q2 form a restart circuit to maintain the chip melody.
Primary: circuit breaker, current transformer, isolating switch, grounding switch, voltage transformer, arrester, electroscope and outlet terminal, etc
Secondary: control cabinet, comprehensive protection, relay and so on
An original; Vacuum circuit breakers. Current transformers.{voltage transformers} ground switches. Insulators. High - voltage fuses. Contact boxes. Busbar sheath busbar splint. Sensors. Second original; Integrated protector. Open and close switch. Red and green button. Red. Green. Yellow light.
High Voltage Switch Parts,Cnc Machined Parts,Milling Spare Parts,Custom Metal Milling
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