GRT Avionics

I'm on the bench with my Mini-X.

My in-plane setup is 2 HXr and the mini-X, which share the dual AHRS and external magnetometer no problem.

On the bench at home, I have no GPS antenna and no external magnetometer connected but want to make the internal mag function.

Ive set Serial 3 to Off, and set external mag to No. I still get no heading info on the PDF; and "Magnetometer Heading" in the AHRS setup is grayed out. The XYZ raw magnetometer numbers are changing and I have about 490 on mag strength. The internal mini AHRS functions as expected.

My intentions are to connect the GPS antenna (new Glissen MCX) when it arrives in the post in a couple of days and finish bench setup, check out maps, and verify comms with one of the HXRs via serial 1. I'm expecting by providing the mini's GPS, AHRS and heading to the HXr, it too will show me maps so I can play with flight planning. Ive updated all the mini s/w to the latest as of today.

What am I missing wrt the mini internal magnetometer??

The internal magnetometer in older Mini displays is for gyro stability only. It does not provide a compass heading. You need an external magnetometer or GPS track with 5+ mph ground speed to get a heading or track display.

Ok wait a sec.

I count at least 4 places in the Mini-X manual that tells me that the external magnetometer is optional for the Mini-X. Which to me means that I get to choose whether I use the internal or external magnetometer. (Its an issue cause my mini-x doesnt want to calibrate with the external magnetometer, tho the HXrs are ok with it...)

But youre saying that internal magnetometer wasnt available for the Mini-X?

I bought the Mini-X to be completely redundant from the HXrs which is what the manual says it should be.

My Mini-X is serial # 650 (which FWIW, I sent in for AoA upgrade along the way.)

Is my Mini-X really an old generation? IF so, can I send it in for "fixing" so I have this choice?

I'm saying the internal one doesn't provide a heading display. The external magnetometer is optional because the AHRS can use GPS track instead and every Mini includes a GPS. Starting with the AHRS hardware in the Mini there have always been two choices for the AHRS heading/track:

1. Magnetic compass heading from an external magnetometer.

2. GPS ground track with ground speed above 5 mph.

Using the internal magnetometer for heading display was never an option. It wasn't accurate enough for that. The internal magnetometer had two purposes:

1. Stabilize the gyros without external magnetometer or GPS track. This helped with initial gyro alignment and maintaining alignment on the ground.

2. Maintain the heading/track display without an external magnetometer if GPS track is temporarily lost.

All newer AHRS hardware including newer Minis don't have an internal magnetometer.

Ok, I understand. Thanks