[aprssig] Mic-E encoding on HF -- does generic SSID path GATE?
Stephen H. Smith
wa8lmf2 at aol.com
Fri Aug 4 14:49:24 EDT 2006
ben at ben.com wrote:
> [this is a duplicate of a message I posted to nwaprssig a month or so ago,
> but I got no reply]
>
> The "Generic APRS digipeater path" encoded in the Destination SSID includes
> all the paths typically used on VHF (WIDE1-1 and up) but it doesn't include
> a SSID for "GATE".
>
> Is GATE implied on HF as a matter of configuration at the receiving station?
> Or does HF APRS need to use dest SSID-0 and encode the GATE,WIDE* path
> longhand?
>
>
You will have to use the explicitly-stated long-form path if you really
want to be gated, but it really isn't necessary anyway.
Nearly all APRS HF receive stations igate received packets directly into
the Internet system, along with any other functions such as cross-band
digipeating.
Gating onto VHF first so that numerous areas hundreds of miles apart
will have their local nets cluttered with out-of-area transmissions on
two meters, that then generate multiple duplicate entries into the
Internet system from 2M is really unnecessary.
Bear in mind that ALL of a packet has to be received PERFECTLY before
ANYTHING is recovered from it. The shorter the packet, the less air time
it takes, and the more likely it is is to be successfully received.
(Less chance to be hit with a pop of noise, a fade or QRM from other
dumb trackers. )
Using Mic-E format on HF with NO PATH at all (i.e. "direct") and no
comment field (just lengthens the packet) is most likely of all to
succeed, since it creates the absolutely shortest possible packet.
--
Stephen H. Smith wa8lmf (at) aol.com
EchoLink Node: 14400 [Think bottom of the 2M band]
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