Re: TI-H: Electronics junk
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Re: TI-H: Electronics junk
>
>I was looking at some schematics and have 2 questions:
>1. How does a relay work? I know it's some kind of switch but thats
all
I think there are several types but a simple one is is similar to this:
there is an electromagnet on the 1st circuit, and, when activated, it
pulls a contact towards it closing (or opening) the second circuit. So
now you can do stuff like power the little electromagnet with a low
voltage circuit and use it to control a high voltage application.
leads to 1st circuit leads to second circuit
______ ______
|| |
|| \
|| 0
------ ------
|| is electromagnet, / is switch... I guess in this example there should
be a spring to move the switch back after the electromagnet goes off...
no space to draw it in...
>2: IN these schematics, it shows where +12V goes into the system but
>doesn't show where -volts goes. Should it go where the schematics show
>ground (I think it's ground, It's a inverted pyramid made with
horizontal
>lines or a tornado) eg.
>--------
> ------
> ----
> --
yup, that's ground... if all you need is +V and ground, then you can
usually just use the -V as ground... at least that works for *most* of
my crude (ok very crude ;) ) circuits... or to be safe you can build a
small voltage regulator circuit (1 78xx, 2 caps) and have a real
ground...
Muhammed
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