Why does an STEC-50 require up to 3 minutes to initialize?

[PeterNSteinmetz]

I was just checking out the auto-pilot in a club‘s Debonair today. It is an STEC-50. You switch it to test and it runs through the test sequence pretty quickly and properly.

You then switch it to operate and the manual says it can take up to 3 minutes to be ready. Why does this process take so long?

 

[Jim Logajan]

Based on material I found on the net, it has gyro which might take several minutes to stabilize or come up to speed after electrical power applied. If it is tied to a GPS it might take a few minutes to get a lock on it location.