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scott45
Joined: 10 Jul 2006
Posts: 3
Location: Indiana
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Posted:
Wed Jul 12, 2006 11:23 pm Post subject:
help building circuit |
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Iam a Aircraft Machanic I work mostly on turbin's I know very little about building a electrical circuit.
What Iam trying to do is build a circuit that runs off of 12 volt AC the power supply is a v6 automobile engine mounted on a frame.
The power lead we are using shows 14.7 volts when the engine is running this is alternater we get the 12.7 volts with engine off.
What I need is a circuit that will set off a alarm or beeper when the voltage gets down to 10.7 volts while the engine is off. The alarm or beeper needs to have a volume controll on it also as we need to here it over heavy equipment at times.
I have talked to alot of people on this and every one is deff on what to do a couple people said to use a LM741 op amp IC, a piezo buzer, and relay.
What we a needing is a circuit that can handle the 15 volts when the engine is running set off a warning of some kind when the engine is not running and sees 10.7 volts be able to adjust the volume of the warning/buzer and a LED so we know its on and working.
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neon
Joined: 25 Feb 2006
Posts: 593
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Posted:
Thu Jul 13, 2006 8:58 am Post subject:
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| An LM741 will work but not as good as a LM139 comparator. You will need also a LM136,236,or LM336 voltage reference. I don't think a piezo can supply the alarm output. You will need a SONALERT or a LM555 oscillator driving a tweeker speaker. Further help is available if you want it. Eventualy the whole thing is a bunch of resistors providing windows of events simple realy. If you want i can design this thing for you free of charge just let me know where to send it. |
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scott45
Joined: 10 Jul 2006
Posts: 3
Location: Indiana
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Posted:
Mon Jul 17, 2006 7:03 pm Post subject:
design |
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| neon wrote: | | An LM741 will work but not as good as a LM139 comparator. You will need also a LM136,236,or LM336 voltage reference. I don't think a piezo can supply the alarm output. You will need a SONALERT or a LM555 oscillator driving a tweeker speaker. Further help is available if you want it. Eventualy the whole thing is a bunch of resistors providing windows of events simple realy. If you want i can design this thing for you free of charge just let me know where to send it. |
Neon that would be great if you could design this I sent pm about a week ago dont know if you got it or not.
Let me know on this we can work somthing out.
Thanks
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neon
Joined: 25 Feb 2006
Posts: 593
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Posted:
Tue Jul 18, 2006 8:22 pm Post subject:
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| just leave an e-mail add here i will send it. I don't think that 12vac can start that engine not unless is rectified and you are using it to charge a battery to start. so i will desgn you the whole thing throw away what you don't want ok. |
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scott45
Joined: 10 Jul 2006
Posts: 3
Location: Indiana
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Posted:
Wed Jul 19, 2006 12:19 pm Post subject:
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| neon wrote: | | just leave an e-mail add here i will send it. I don't think that 12vac can start that engine not unless is rectified and you are using it to charge a battery to start. so i will desgn you the whole thing throw away what you don't want ok. |
Ok sound good Thanks again
Scott
Scott@rushvilleindiana.us |
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