electronic kits engineering We—148 Birthday Candle

This is a experimental product which simulate real candle, that can be lighted and extinguished. When lighted, it plays birthday song, and when extinguished, stops the song. This can make your birthday jubilantly. It uses switch SW2 and MK1 to realize the function of lighting and extinguishing, when the LED is lighted, it would be candlepower. So its function is listed as following: 1. Lighted ?Q3 Q4 form bitable trigger circuit. When you press switch SW2, Q4 collector voltage reduces, Q3 base voltage reduces, Q3 collector voltage increases, Q4 base voltage raises, Q4 collector voltage drops, then the circuit reverses, Q3 stops, Q4 saturated. Q4 collector lower output makes Q5 saturates and circuit goes smooth, then IC will make it plays song, happy birthday. 2. Blowed off by mouth When blowing to MIC, MIC will induce an electricity signal, and magnify by Q1 Q2, then changed into positive pulse after through diode D1 and go into Q3, Q3 base voltage raises, Q3 collector voltage reduces, but Q4 raises. Then both reverse again. Q3 saturates, Q4 stops, Q4 has high output that makes Q5 stops, LED is off. Then IC also stops playing music.

Category:

Science & Technology

Tags:

• educational
• toys
• electronic
• kits
• science
• activity
• children
• technology
• computer
• mechanics
• robots
• diy
• present
• soldering

[happygamestvfun1]

i can write software to do this, big whoop...

[karatemark27]

this is cool

[petermok387]

very good