[aprssig] some questions about APRS queries

Michael Conrad do5mc at friggleware.de
Sun Oct 5 06:50:20 EDT 2008

Hi all,

I'am implementing a query module for my APRS software, but have some trouble with
the ?APRSD and ?APRSH queries (page 79 of APRS Spec 1.0.1).


1. How long after the last beacon a station should be reported as heard direct ?
    (Using net cycle time of 10 minutes could be to short.)

2. What happen, if more stations were heard direct, than fitting into one response ?
    (In average about 30 stations would fit into one response message.)


3. Is one hour counted from 00 to 59 OR 60 minutes back from the time the query was received
    by the station ?
    (The first one is much easier to implement (but requires a absolute clock), the last one is more exact.)

    Reading the spec, I assume the first one is right ("in each of the last 8 hours").

Thanks in advance

      Michael, DO5MC

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