[OZAPRS] APRS with Foundation license

Warren VK3BYD vk3byd at wia.org.au
Wed Oct 6 11:04:47 EST 2010


Hi Richard,

I depends how the station is transmitted.
If I use a TNC and send my transmission direct (and only) to RF then the
rules for AX25 apply and SSID is encoded into the transmission as 0 - 15.
However if I send my beacon only via Internet then it is treated as plan
text so the SSID could be any ASCII character.

Cheers
Warren. 

-----Original Message-----
From: ozaprs-bounces at aprs.net.au [mailto:ozaprs-bounces at aprs.net.au] On
Behalf Of Richard Hoskin
Sent: Wednesday, 6 October 2010 10:47
To: 'Australian APRS Users'
Subject: Re: [OZAPRS] APRS with Foundation license


Hi Ray,

> I have to confess I do not know what would happen with a seven character
> callsign but given that the last character ends up where the SSID is
> expected, one could expect packet corruption. I'm just looking at the
> v2.0 (1984) specification and the source address field is seven octets
> long. The first six are for the callsign, the seventh for the SSID. For
> a callsign with less than six characters, the space to the right of the
> last character is padded with ASCII spaces. The dash, between the
> callsign and the SSID is not mentioned but appears to be a delimiter
> after the callsign. Given that the SSID field expects certain ASCII
> characters and, another letter may not meet the requirement, I stand by
> my assumption that packet corruption is a possibility.
 


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