Help with compatibility upgrading my equipment

[AntonioBindi]

I was very glad to find this Forum, and impressed at the responsiveness. I am in Brazil, and struggling to find well-prepared technical assistance to help me adapt my current configuration instead of trying to sell me "everything new".

I just bought a 2003 Hunter 466, that came with a bunch of Raymarine electronics (some in need of substitution / upgrade). I would like to know what items can I save, when upgrading my chartplotter to a MFD. I am quite a layman regarding the electronic parameters, although some reading has put me understading a bit.

My current configuration is as follows:

At the helm (picture attached):
- ST60 Depth Display (busted screen, alarm will sound but buttons won't work)
- ST7001+ Autopilot (working fine. I fixed the screen after the picture was taken)
- ST60 Speed Display (works occasionally. I may have to get new speed transducers)
- A57D Chartplotter (which is the only device displaying AIS information. Not sure where the AIS data is being generated though - I haven't digged the boat enough to find it yet)
- Garmin GPSMap 2108 (not a big fan, as I was used to a touchscreen version on previous boat.
- ST40 wind instrument (actually, 2 of those)


At the Nav Station:
- SL72 Radar Display (not working - Powers on, but no display or button sounds)
- RC435 Chartplotter (works, but I never use it)
- There is a "400 course computer" hidden in the cabinet, which I believe is related to the autopilot.

There are at least 3 external GPS antennas around the cockpit (not sure why so many)
There is a Raymarine Radome on the mast (not sure what model, but certainly installed in early 2000's, if that helps).

My idea here was to upgrade the helm instruments to a 9" MFD (a98 possibly), with all the functions integrated (Chartplotter / Radar / AIS / Depth etc), and keep the autopilot (don't want to upgrade this expensive unit now)

If everything works as intended will probably get rid of the RC435 down below, and reposition the Garmin 2108 and the A57D somewhere inside, for some redundancy.


My questions are:

1. Will my current autopilot work with the a98, accepting their full routing capabilities (Navionics routes, etc?)

2. If I want to upgrade my current st60 wind / depth displays to, say, i70 multifunction displays, will I need to get new wind / depth / speed transducers for them, or will my old ones be compatible? Any converters necessary?

3. I am aware I would need a new digital radome, since my old one is not compatible with the a98. Will the Rd418Hd Radome be also compatible with the Garmin 2108, as a second screen downstairs? If so, will I be able to use both the Garmin and the a98 simultaneously?

4. Will my AIS unit (currently feeding the A57D) be compatible with the a98? Will I be able to feed the Garmin AND the a57D simultaneously? (same question as 3)

5. If I DO have to upgrade my depth transducer, I am considering getting a thru-hull with Downvision because... why not? Will it send basic depth data to all my equipment?

6. Do I really need a separate external GPS antenna for each of the displays, as it's currently installed?

Thank you, for any help with this.

Cheers!

Antonio B.
Rio de Janeiro, Brazil