I think an useful feauture could be “Spotter maximum distance”, especially for VHF ES propagation, where the path is very localized. The distance could be calculated from the main square. I think the only possible source would be pskreporter.
For now, my workaround is to include a lot of particular calls on the radius of interest (for example 100km from me) but this list needs to be revised quite often, new calls becomes active. However, the trigger worked wonderfully for most of ES and DX tropo openings.
Any opinion on this?
I still consider it’s good to have useful alerts for very localized ES, TEP, ducting, etc.
For now I need to manually maintain a list of active calls on each band (2m, 6m, 4m) who are on a particular radius (for example 80km) from my QTH.
I guess the issue is where to obtain accurate data on callsign location from, in order to have a universal solution that works for callsigns worldwide and regardless of the spot source. QRZ.com comes to mind with their API, but based on a recent inquiry to their staff about bulk lookups (Trigger "QRZ.COM entry exists" for callsign pse? - #4 by HB9DQM) I don’t think this would work in practice at HamAlert’s scale.