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Old April 27th 04, 12:33 AM
Tim Wescott
 
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Tom Kreyche wrote:

Does anyone have sources for analog meter movements that can rotate at least
250 degrees? I'm building a custom rate-of-climb instrument for my glider.

I found one source at http://www.us.yokogawa.com/MI/ but their smallest
off-the-shelf unit is a bit large at 50x36mm. It uses taut band technology.

I've been trying to find a source for air-core movments but web searches
only show up people selling automobile tachometers. I'd can drive the meter
with PWM or DAC or whatever.

Thanks, Tom



So what's the matter with an automobile tach? They're all electronic
these days, so you drive them with a pulse train who's frequency is
proportional to the reading you want to see.

12000 feet = 12000 RPM (assume you can get one that high) = 200 rev/sec
= 400 pulse/sec for a 4-banger.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com