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I'm designing an altimeter based on a pic microcontroller and a freescale pressure sensor.

I'd like to output the altitude from the pic using an analog gauge. I found some useful information here.

What I want to know is where to buy analog gauges that allow me to put my own scale (I'm basically looking for the raw ammeter)

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Padu Merloti
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3 Answers3

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You should be able to buy the 0-5V voltmeter from Futurlec, then drive it using PWM from your microcontroller. I think using a voltmeter is more efficient than an ammeter, unless it's a very small range ammeter (otherwise, if it's a 0-100mA ammeter, you'll need to waste 100mA just to move the needle to 100%).

The volt meter I linked to can be opened, and you can replace the scale with your own (or just glue your own on top of it).

davr
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Perhaps try IMS? I believe they're in southern California.

By the way, A PIC will output a voltage more easily than a current, so you're probably going to want a voltmeter rather than an ammeter (maybe you knew that already). You could always use a handy voltage-to-current converter (a "resistor") to make a current from a voltage, but it's simpler to just read the voltage directly.

pingswept
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RS sell a range of meters with blank scales - example link. You could also use one with a pre-printed scale and calibrate your output signal to give a meaningful reading on the scale.

As with most of these questions, you forgot to say where in the world you are. If RS do not cover your area then Farnell cover more countries - Example link

uɐɪ
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