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clap switch

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rahulmodi

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CLAP SWITCH

general description
used to turn a device on or off by sound only, eg; clap. when triggered in ckt. it will stay on or off till triggered again.

how it works
ckt has 2 stages - preamp usin trans. q1 4 amplifying mic signal. second consists of 2 transistors q2 and q3 as a FLIP FLOP. (can some one explain this part of the circuit to me.)
flip flop is triggere by preamps o/p. it in turn triggers o/p transistor q4 which controls relay. (can someone explain connection of a 5-pin relay to me. is my interpretation at the bottom of the page correct.).
with each change of state of the FLIP FLOP o/p transistor will be forced to chage state being on or off. this in turn turns the relay on or off. relay is changeover type and it's contacts are rated 220 v/ 3a/6a. microphone is condensor type 4 gr8er sensitivity.
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Russlk

New Member
The schematic shows Q3 only connected to R11, which makes no sense. If it were connected to R9, there would be positive feedback that could latch the circuit. I looks like a very unreliable design.
 
H

hyedenny

Guest
Hi,
How about using an opamp output with one decoupling capacitor, one bypass capacitor, a resistor, and a diode to square up the output.
Then either input to a microprocessor, an SCR, a transistor, a flip-flop, or some other kind of latch. Your parts count would be much smaller.
 

rahulmodi

New Member
help on relay connections

hey thanx a lot guys 4 replyin
i'll think over ur suggestions.
can you help me out with connections for a 5-pin relay with terminals

. . NO
. COM
. . NC
 
H

hyedenny

Guest
NO stands for "Normally Open," NC stands for "Normally Closed," COM stands for "Common."
Common goes to ground, and you have to choose whether to use NC or NO depending on what you want to do.
Most relays have little schematics of their circuitry printed on the side.
 
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