working a real gauge without PMSys.

[mauriceb]

Just a reminder folks that the time constant formula is Megohms x Microfarads and not K ohms. With the values shown, the capacitor would charge pretty much instantly.

Maurice

[Jackpilot]

so.... I do not want to smoke my gauge!!??

[mauriceb]

so.... I do not want to smoke my gauge!!??

so.... I do not want to smoke my gauge!!??

???? No idea what else you want to smoke , but if this is in response to my comment about megohms, the higher the resistance, the less current through the gauge and less possibility of smoking the gauge.

Having said that, I don't think this circuit will accomplish what you want to do, namely have the needle go up slowly. With the values that you showed, the capacitor would charge pretty much instantly and once the capacitor is charged, the gauge would receive all the current that goes through the pot .

No harm in trying though and the only chance of damage to the gauge is if the pot goes to zero ohms or close to it, so as Mike said, you need a resistor in series with the pot to avoid that possibility.

Maurice

[Jackpilot]

Check Y.ca

[Matt Olieman]

and.... after you get this monster working.... we want to see pics or better yet video

Matt Olieman

[Jackpilot]

You bet!!!

Posted another crazy idea for the trim gauge too....

Having fun anyway,,,

[Mike.Powell]

Just a reminder folks that the time constant formula is Megohms x Microfarads and not K ohms. With the values shown, the capacitor would charge pretty much instantly.

Maurice

Even though the resistance is in KOhms and the cap's in microFarads, the time constant is about a second because it's a big cap.

1 K * 1,000 mFd -> 10E3 * 10E3 * 10E(-6) -> 1

[mauriceb]

Even though the resistance is in KOhms and the cap's in microFarads, the time constant is about a second because it's a big cap.

1 K * 1,000 mFd -> 10E3 * 10E3 * 10E(-6) -> 1

My mistake . For some crazy reason, I missed the 3 zero's following the 1. Need more diet coke to wake me up

Maurice

[Jackpilot]

IT WORKS FINE

made a video but what I have is a .MOV format
Do not know how to upload it

Very happy...will allow populating the NG with live analogs..brake pressure/Hydraulic/ temperatures/ APU EGT/Oxygen etc...

Parts cost about $5, gauges average $20 on EBay

[Matt Olieman]

Jack, upload it at www.MyCockpitVideos.com if you haven't' registered there yet, you'll need to do that. Pretty simple to upload it.

Then you can link it to one of your post here, or I can do that for you.

Matt Olieman