[aprssig] Digipeater addresses/spec question

Alexander Sack pisymbol at gmail.com
Wed Jul 20 11:19:05 EDT 2011

On Wed, Jul 20, 2011 at 10:57 AM, Lynn W. Deffenbaugh (Mr)
<ldeffenb at homeside.to> wrote:
> On 7/20/2011 10:51 AM, Alexander Sack wrote:
>> Yes I got that this from Bob's page on SSIDs (thanks).  But the spec
>> seems to insinuate that AX.25 Source addresses have SSID's which is
>> again the source of my confusion.
> Yes, in AX.25, all station addresses in the header, including the source,
> destination, and all path components, have four bits reserved for the SSID.
>  When these packets are put into human-readable form, the -0 is typically
> suppressed and presented as just the callsign with no -SSID.
> So, every station address in every packet on the air will contain an SSID
> from 0 through 15 inclusive.  But the human readable packets will suppress
> the -0 for convenience.
> Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32

Thanks guys (Stephen, Lynn, Bob, etc.).  Okay, that makes way more
sense.  So its my radio's parser output.  All makes sense now.

-aps (KC2ZSX)

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