[aprssig] Invalid object

Heikki Hannikainen hessu at hes.iki.fi
Mon Mar 29 07:41:59 EDT 2010


On Mon, 29 Mar 2010, Keith VE7GDH wrote:

> Lynn KJ4ERJ wrote...
>
>> Why all the spaces after the object name and before the coordinates?
>
> AA3NJ>APGO01,NV4FM-5*,N3KTX-1,qAS,KB2CEV:
> ;MDEVNT1  *       3911.13N\07640.30W!
> Action Event @ I-195 EAST/WEST SOUTH OF MD
>
> Object names must be 9 characters, or padded with spaces... e.g. the object
> name above is "MDEVNT1  ".  The asterisk indicates that it's a live object.
> However, the time stamp appears to be missing. There do seem to be seven
> spaces there which is the number of characters used by the time stamp. The
> spec does indicate "an object always has a time stamp" so the time appears
> to be missing.
>
> Looking back to the original message from Rob AA3NJ he was asking
> why his objects were marked as "invalid object". I would  be willing to
> bet this was because of the missing stamps.

You're probably right - the decoder used by aprs.fi requires that the 
timestamp is there. The easiest way to figure out the errors is to find 
some packets for which there are no error messages in the raw packets 
display, and to compare against them. The missing timestamp should be 
obvious from there. The raw packets display of aprs.fi can also show 
packets in a "hex dump debug" mode, and the decoded packets too.

Like advertised for quite a few times, the decoder can be downloaded at:
http://search.cpan.org/dist/Ham-APRS-FAP/

See FAP.pm, sub _object_to_decimal for details.

   - Hessu





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