You could try **broken link removed**.
The circuit generates a longer pulse from a short voltage impulse from the transducer.
It might need quite a sharp shock. Anyway, you'll need to do some experimentation with this to get it just right. I'm guessing this is for the security alarm? If so,
perhaps it would be ideal for detecting breaking glass or something.
o yesss sir you are right but not only for security but for some other purposes im making it & all are dealing with plans to help mankind & too its for my personal use too thanks a lot sir let me do practicals on it first
hello sir the link you ahve given here containing a circuit duagram proper to my need but having to resistance value undefined have a look again please . So please let me know about its value sir , im on my practical board now . . .thanksss
The resistor on the left can be (say) 10k. The resistor next to it depends on how long you want the LED light up - the formula for that is on the
555 wikipedia page (page-down to monostable). If the circuit doesn't work when the piezo is tapped, then try swapping the piezo leads
around (I've not tried this circuit. It's not brilliant, but should work..).
yo sir its working but not very much sencetive but enough reasonable for me to solve my purposes thanks
okk tell me how to make a simple remote sensor using tsop 1838 photo transistor , & a few npn pnp transistors resistors & capacitors.i dont want to use any ic here but want to solve the purpose with the few.please tell . . thanks
Heres a circuit, but
note the "piezo buzzer" in the circuit is not the same as a "piezo element". Replace the piezo buzzer with an LED
and resistor (470 ohm) if you like.
You coud use a MOSFET instead of a transistor, e.g. IRFZ44. Or use a bigger transistor.
See section 8 of this web page on how to connect up the mosfet.
Also stick a 1M resistor between the G and S pins, and a 1k resistor in series with point (B) and whatever you're driving the MOSFET with, e.g. switch or 555.
For the diode, use any diode you have handy.
2N3055 should be fine it's a NPN BJT. It's a bit big. If you wanted to use a MOSFET, then virtually any N-channel enhancement MOSFET should be fine.
IRFZ44 is very popular. What N-ch MOSFETS are available where you are?
sir it is popular i know well im watching it all over since 4 years but strictly in our area so far but failed to get it so pleasee let me know the substitute so as to proceed my experiments sir thanks
Any n-ch enhancement mosfet. e.g. BS170 is good for 0.5A, which should be sufficient for a small motor. Or 2N7000.
There are thousands, if you go to farnell.com, you can search for different ones, just select Semiconductors->MOSFET->N-ch.
ya okk i got the list now let c if these are available or not , well thanks a lot lot lot sir let me complete the practicals on the above description properly & clearly
Not sure what you mean.. You can use a 555 in monostable or astable mode, as you saw on the wikipedia page.
You're now familiar with both modes - astable for the DC motor control that you were interested in, and monostable for the piezo trigger.
You're also now familiar with driving a motor with a transistor or MOSFET. What do you mean by simple switching mode?
but i made this practical twice no result as shown here in picture so i need the same operation but the correct circuit not this one its not working simply as it needs proper biasing which is not shown
I'm not surprised it didn't work, the circuit there is incomplete. It has no resistors or capacitors. The wikipedia page shows how to correctly use the 555.
Your piezo circuit can be used. Just replace the piezo with a switch.
Refer to my post #10 and connect one end of a 1k resistor to point (B) on the MOSFET cct, and the other end to pin 3 of the 555.
best personal alarm i have seen used a 1"d piezo sensor with ball bearings to amplify motion for security alarm and small autotransformer to boost 9v to >>100v with resonant alarm sound on same sensor