mviowa wrote: ↑Tue Oct 11, 2022 7:50 pm
To start, I'm a huge fan of MGL. From a technical perspective, I like the design. While I was drawing up my installation documents, I was thinking about a few alterations that would appeal to me and drew them up. Just sharing to see what others think.
Here are the key points I wanted to accomplish:
offload AD from iBox (redundant pressure transducers over can bus? just replace the sensor module if it fails.)
eliminate the hose barb from AD sensors ( I like threaded)
eliminate 'jumpers' and resistors; incorporate into hardware design with dip switches
switch to Amphenol aerospace connectors
Let me know what you think!
I enjoy seeing posts like this because I enjoy seeing the enthusiasts at work.
One thing though that I did want to mention is that unless you expect to see these products in Bombardier Challenger aircraft, the majority of consumer avionics will never see AMP aerospace connectors. The price of just one MIL-SPEC connector is a factor of 10 above a d sub, and d subs are proven to be great connectors in pretty much all brands of GA avionics, and even in many part 25 aircraft these days.
I will say that from a wiring standpoint I agree that being able to enable CAN termination on a per-unit basis would be nice, as opposed to doing so on the harness. That said though, coming from a support standpoint, the reason many of these jumpers exist on the harness side is so that if a unit ever needs replacement, there is minimal configuration on the unit itself ultimately reducing support calls and downtime because someone forgot to or doesn't know about turning on the termination resistor.
While I am 100% on board with you on moving to threaded pressure connectors, offloading the air data from the iBox (or EFIS itself in most cases) and onto another unit doesn't really seem to me like you're solving much. Pressure sensors are probably one of the least troublesome things that I am aware of and making a new unit dedicated to air data will only serve to take up more space, use up more precious microcontroller chips that we desperately need, and adds additional wiring complexity to the CAN bus. In one example you're moving the AD to the SP-9, making it an ADAHRS but other than copying Garmin's method, you're only moving the sensors to another box that would still need an entire replacement if the sensors did go bad.