[aprssig] APRS-IS Object Filter Syntax

Keith VE7GDH ve7gdh at rac.ca
Fri Apr 19 12:20:25 CDT 2013


Peter VA3YOW wrote...

> I would like to filter objects by 1) name and 2) Distance if possible
> I have tried the o/ command using it similar to p/ but didn't work.
> Anyone know what o/ syntax will work to filter specific object
> prefixes and or distances?

It might be worth looking at the "type" filter...

------------------------------------------------------------------------
Type Filter
The type filter will pass traffic depending on the packet type.
More than one type can be defined in one single command. You
can also limit this to a distance around a station or object.

Syntax:   t/type
                t/type/CALL/dist

Where:   t = type command
         type = is one or more of the following letters
              p = Position packets
              o = Objects
               i = Items
             m = Message
              n = NWS Weather and NWS Area Objects
             w = Weather
              t = Telemetry
             q = Query
              s = Status
              u = User-defined
CALL = callsign of a station or name of an CALLobject
    dist = distance in km from CALL to pass this type

Samples:
t/p   This will pass all traffic with a position
t/w This will pass all weather traffic. For
       positionless weather objects the corresponding
       position packet will also be sent when it is
       next heard
t/mos This will pass all messages, objects and status traffic
t/p/SM5NRK/500  Pass all position packets within 500 km
      from last known position of SM5NRK
------------------------------------------------------------------------

You could request objects within X km of a particular station.

Of course, if you know the name of the objects, you could just
use the object filter and request specific objects. However, the
type filter would allow you to fetch certain objects based on
their location without having to know the exact name of them.

73 es cul - Keith VE7GDH
www.ui-view.org
--
"I may be lost, but I know exactly where I am!"



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