Question about electric trim

[cessnadriver1]

I am currently flying a Cessna 182 but hope to start building a 7 soon. I had a question about trim, specifically electric trim. I currently fly with a manual trim tab and it is nice to have the "takeoff" position easily noted. Is there a gauge or device that one can use with electric trim for this? I have recently gotten my taildragger endorsement in a Citabria and the way to check correct trim position was to turn around and look at the tail and line up the tab and the elevator. This is fine as well but I was wondering if there is such an item to be able to see the position of the trim tab?

[TX7A]

Yes. There are different options available. Even some of the EFIS boxes can show trim indication depending on set-up.

[Buggsy2]

The electric trim Vans sells uses the Ray Allen servos and indicators I believe.

[DCat22]

Originally Posted by Buggsy2

The electric trim Vans sells uses the Ray Allen servos and indicators I believe.

Yes.

And if I recollect, the servo includes a simple slide potentiometer to output the servo's position that can be read by "whatever".

[Mike S]

Originally Posted by DCat22

Yes.

And if I recollect, the servo includes a simple slide potentiometer to output the servo's position that can be read by "whatever".

You recall correctly.

The servo has 5 wires in it, two for the motor, and 3 for the indicator feedback.

[CODon]

5 wire as stated above. I did have EMI problems with the indicator and had to shield lines. Some folks do and some don't and probably driven by routing and the Ray Allen indicator. There does not appear to be a 5 wire shielded cable so ended up with a three and a two. Ray Allen said they did not know of problems,but did later admit that they were working on a different power supply, so they knew. Spent 3 days chasing problem with one of my satellite electrical guys and we definitely tied it to interference. Hope you don't have a similar problem, but just wanted to minimize your troubleshooting if you do. Don