The KMD does NTSC video, and this is used for onboard radar. I have this connection in mine and have successfully tested it, as described here. However I don’t plan to keep the KMD for a long time; the centre stack update would displace it. I will keep the Sandels though. Not sure what they can display, but google/images instantly shows this
That pic also shows traffic, ex TAS6xx in my case, exactly as I have it. From the IM:
Data Link Weather Option
The SN3500 supports Flight Information Services-Broadcast (FIS-B) data link
weather (precipitation and lightening), input via a single RS-232 Input from a WSI
Data Link receiver in software version 3.00 and above. Purchase of a key code to
enable the weather display is required.
I have the wx500 displaying on it already, but that just shows strikes.
A thread hijack though 
as I am probably the only person doing this.
Peter wrote:
WSI Data Link receiver
I fear that is XM weather only. Also 2005 would be rather early for an ADS-B UAT FIS-B signal integration.
Peter wrote:
KMD does NTSC video
I looked into generating PAL/NTSC video signals as that would also feed the G500/600 devices. But I fear the image quality would be bad due to different resolutions, the weather data would not overlay on the navigation data, it would simply use the screen space to display some radar only image. Also Garmin seems to charge 1,5k to get the video feature unlocked and the ADL devices would need a serious upgrade to output NTSC/PAL. So eventually I decided this was probably not the way to go.
Since WSI pulled the plug there is an opportunity to get ADL weather on a sandel with an unlock fee? I would be interested :-).
The install manual shows that the SN3500 input is one RS232 line and further two on the 429 input…
from aviation consumer:
https://www.aviationconsumer.com/avionics/sandel-sn3500-ehsi-pricey-performance/
The traffic and weather inputs requires a special software key that adds about $1500 to the price-$714 for each software key to be precise. The traffic option includes most types of traffic formats, but the SN3500 only accepts WSI weather, not XM-based formats._
Generating NTSC video is easy but yes it is more electronics… and almost nobody in the marketplace will be able to use it. Not sure how you could georeference it, too, because you can’t know the screen centre lat/long and the scaling for the display device. When ADL data is displayed within the ADL app, there is total control over the map position and scaling, which enables georeferencing, which leads to the Q of how is georeferencing achieved when ADL data is displayed on an IFD540?
Is there a spec for the WSI wx data stream? The ADL data starts life as bitmapped images.
Both my SN3500s already have the keys for stormscope data display, traffic display, and the roll steering option.
As an aside, years ago somebody developed client-side code for a browser which displayed the meteox.com radar image, georeferenced! The browser, running on a phone, or on a tablet with GPS, had access to the GPS location. It did actually work, almost… It was implemented on a private site. So even a browser is capable of displaying a georeferenced image, so Sebastian could port his system to be entirely browser based.
