[simpits-tech] N1 & N2 Gauges

[David C. Allen]

Jeroen
Since I have not found the overhaul manuals for the instruments, my next
step is to find a generator and take it for a spin.

Thank you for your ideas and I will let the group know what voltage the
generator outputs.


David
N9070U 737-222



On Mon, Aug 7, 2017 at 12:42 PM, Jeroen Huijben <jeroen_huijben at hotmail.com>
wrote:

> I presume that you want to leave the gauges intact.
>
>
> The simplest method would be a three legged H bridge consisting of a pair
> of FETs per phase.
>
> Then the microcontroller would cycle each phase through high, low and off
> in the proper order and phase offset.
>
> Then you would increase and decrease the rate with the engine RPM.
>
>
> If that turns out to be too crude you could PWM a sine wave.
>
> Then you use an opamp to buffer it, and then add a 120 degree phase
> shifter, second buffer, second phase shifter and third buffer.
>
> If the gauge requires a lot of current you can add another amplifier to
> each phase's buffer..
>
>
> Or use three PWM outputs and let the microcontroller deal with the phase
> offset.
>
>
> Any idea on the gauges voltage and current requirements?
>
>
> Vriendelijke groet,
> Jeroen.
>
>
> ------------------------------
>
>
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