Andrew Gideon wrote:
How "particular" to an AP are DGs?

We're looking to replace a DG in an aircraft that has an [original] Cessna
Navomatic 300A (I think it is called) autopilot. In the not too distant
future, we'll be upgrading the AP (probably to an STEC unit, likely to the
STEC 20 (we already have the STEC 30 Alt installed)).

Would we need a new DG when we upgrade the AP?

- Andrew

The STEC autopilots are rate based and get their control information
from a special turn coordinator. The DG heading bug is fairly generic
and only plays a factor to tell the DG a desired heading when in that
mode.