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amplifying a voltage signal


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In my wiring escapade I have come across another obstacle.

 

You've heard of voltage reducers (usually 12V to 6V)

 

Well, I need something to do just the opposite. I have a component that is outputting 0.07V (that's 70 millivolts), and I need to boost that signal to somewhere up around 1 volt, because the component receiving the signal is not recognizing such a low voltage signal.

 

Is there some way to do this?

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what are you trying to do? turn on a amp or something in the truck? most 12v relays will close with .07V, so maybe you should use that signal you have to close a relay, and then have the relay send people to whatever you're turning on, you'll have 12 as the unit then. just an idea

 

Jacob

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In my wiring escapade I have come across another obstacle.

 

You've heard of voltage reducers (usually 12V to 6V)

 

Well, I need something to do just the opposite.  I have a component that is outputting 0.07V (that's 70 millivolts), and I need to boost that signal to somewhere up around 1 volt, because the component receiving the signal is not recognizing such a low voltage signal.

 

Is there some way to do this?

 

 

 

 

It would help if you fed us some more details. I can show you how to build a DC voltage doubler but that won't get you up to 1 volt.

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Thanks for the responses. I'm still trying to get this cell phone kit to work right. It's supposed to mute my stereo whenever I receive or place a call. It's supposed to do this by putting voltage on one of the wires in my stereo harness, but so far it's not doing the job.

 

I wanted to test the stereo harness wire (I thought maybe I was splicing into the wrong one), so I put 1.5 volts on it with a D-cell energizer battery, and sure enough, my stereo muted.

 

So now I know I have the right stereo wire, and I measured the voltage on my cell phone output wire (the one that's supposed to send the signal to the stereo wire), and it puts out zero volts when I'm not on a call (as it's supposed to), but only 0.07 volts when I place a call with the kit.

 

From all that, I determined the following:

 

1. I have the right stereo wire

2. My cell phone kit's 0.07 volts is not sufficient for my stereo to recognize the signal.

3. 1.5 volts is sufficent, but I could probably get by with less.

 

I have been told that I should use the smallest voltage level I can get by with, because the system's full 12 volts can damage the computer data bus thingy.

 

The instruction manual said I may have to use a relay, but I was not aware that 0.07 volts was sufficient to close a relay. Also, even if this works, how will I reduce the relay's load voltage from 12 down to 1.5 or less? I know voltage reducers exist, but I've only heard of the ones that reduce 12 volts to 6 volts.

 

Thanks, guys. I was beginning to think I'd just have to live without this feature.

 

Jon :smash:

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Well, I finally got it working.

 

I had reported the voltage wrong in my earlier post. My kit was actually only putting 10 millivolts on the mute wire, not 70.

 

At first, this seemed to present an even greater problem. However, I learned a new piece of info that solved everything:

 

The head unit has another mute input back there. The one I was tapping into was on the 24 pin connector, but there's also one on the 12 pin connector too. This one's designed to receive a very low (such as 10 millivolts) signal. When I tapped into this wire, everything worked beautifully.

 

Now when I place or receive a call, my stereo mutes, and it says 'Phone' on the face of the head unit. Here's the diagram of the connector pins. Again, if anyone uses this feature, the low-voltage terminal is on the 12-pin connector, as marked in pen.

If you were going to send audio feeds, it would be through the Audio (+) and Audio (-) terminals, also marked in pen. My kit did not have this feature, so I'll just have to use the speaker that came with the kit.

Anyways, here's the diagram (it's a pdf file, so I can't display it within the post):

 

 

http://bama.ua.edu/~roden001/GMBose_w_OnStar.pdf

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