I have acquired a KX-155, KLN-89B and a 209A indicator. The 209A has a built-in relay to switch between the GPS and NAV. I'm trying to figure out what 'annunciation' is _required_ for this setup. The MD41 annunciator is about $950. I can get the control head only for about $700.

The real question is do I have to have this? $700 seems like a lot for a couple of switches and some lights! Can I not have a simple toggle switch on the panel to switch between NAV/GPS and let the 89B do all the annunciation?

Matthew