[aprssig] Q: Paths and the D700 and Digipeating in General (LONG)

Robert Bruninga bruninga at usna.edu
Tue Jun 7 11:40:11 CDT 2005

>>> noskosteve at yahoo.com 06/07/05 12:21 PM >>>
>Will a digi set for ALIASES of TEMP,WIDE1-1 digipeat
> a packet with _either_ a path of TEMP  *OR*  
>WIDE1-1   in the first slot?


>With a path of :      XXXX,YYYY
>Is it true that this packet will ONLY be 'peated by 
>a Digi with XXXX in its list? 


> In other words if no XXXX Digi hears it, it dies, 
>forever lost in the ether, even if a YYYY Digi hears it?
Yes (though I think that some of the very special
software digis can do what I called preemptive digipeating
and can do it.  But these are rare...

>Then the XXXX Digi transmits it  (marking XXXX 
>with  *) and only a YYYY digi will then 'peat it?

>So, Digis look for the first alias without  * and if 
>it gets a match with *any* in its list it  repeats it?

===  Part two  GATE question  ===
>In the HF case (1st excerpt below).  The recommended path 
>               GATE,WIDE2-1
>means that ONLY a GATE will take this packet off 
>the RF network, right?______


>Then, after the GATE gets it, it will only then 
>be digipeated by the true WIDE (assuming it has 
>the WIDEn-n software)?___

>  Except,  is this from the HF side *to* 2M or  
>from 2M to HF -- or does it matter -- ?_____
ONLY from HF to VHF.  It doesnt hurt to add
a few packets from a few HF mobiles into a
few VHF networks for one hop only, but it is a
NIGHTMARE if anyone does it from VHF to HF
because there are 800 such VHF networks
all operating at 1200 baud and the HF network
can only handle a few users at 300, so
never, go from VHF to HF.  

If one wants to play on HF, one should get an
HF rig...

 >Moving to (the final) PART 3 a related topic "Call Substitution"
Without this, I believe each Digi that  'peats a packet puts an asterisk (*) in the field of the path designator it "used" ??   Hmmmm  Peter piper 'peats a peck of 'peated packets...

*With* Call Substitution, we will see (within the 'peated packet) a list of calls of the digis that handled this packet, right?  I think the last one will have the *   I look @ the findu raw packets and next hope to follow the q construct information there...'cept I don't really know wht a "client" is...
Call substitution worked back when we used multiple
hop entries like RELAY,WIDE,WIDE so that it would
arrive as DIGI1,DIGI2,DIGI3*.  But no we only do
WIDEn-N so there is no "callsign substitution" but
we call it "tracing" where the digi inserts its callsign
in front of the WIDEn-N if it digipeats it.

>What is the stuff immediately after my call 
>(T2PS9Y) in the APRS-IS packets on findu

It is the TOCALL.  But since APRS is to everyoone
we use those 6 bytes for other things.  Usually for
the APRS version number or for Mic-E style packets,
for the LATITUDE and message bits encoded.

K9DCI-9>T2PS9Y,WB9WLS*,WIDE2-2,qAR,KH6KI-1:'tZdl,M>/]Steve Wonder Lake IL 145.410   ???

==========   EXCERPT #1  =================
Date: Fri, 03 Jun 2005 19:26:27 -0400
From: "Robert Bruninga" 

Subject: Re: [aprssig] HF and the new n-N paradigm, mobile digis

Good questions!

>What would be the recommended path for APRS 
>mobile/portable stations on HF? ... the old way 
>was to use GATE, WIDE ... Would the new way
> be GATE, WIDE1-1?

No, because the special path of WIDE1-1 is for
use by home and fill-in digis only. So better to
use the path of GATE,WIDE2-1. It is still only
a 1 hop path but does not key up home stations.

>Also, is there any convention in place for a standard 
>alias to be used for a mobile digi? For example, ...
>I've got a pockettracker.... to make it back to my car

Yes, set your D700 to digipeat by using a PC to enable
its UITRACE parameter with the permanent alias of
TEMPn-N. This way, any mobile any time can be used
as a temporary digi, but all the other time, the digi does
not digipeat any normal on-air packets and so does not
add any problems. But is always available.

de WB4APR, Bob

==========   EXCERPT # 2  ================
Message: 9
Date: Sat, 04 Jun 2005 09:50:53 -0400
From: "Robert Bruninga" 

Subject: [aprssig] Mobile Digis (New -N Paradigm)
To: , , "Robert Bruninga"

Content-Type: text/plain; charset=US-ASCII

We should add this recommendation formally to the 
New-N Paradigm. This will go a long way towards
common and consistent use of pocket trackers and
other temporary applications:

D700 user's should be aware of these settings:


Set Tracket to 144.99
Set D700 band B to RX 144.99
Set D700 band A to TX 144.39
Set D700 TNC to RX B & TX A
Set RADIO-TNC-DCD to both A&B
Save in a PM just for this application
Set pocket tracker to use path VIA WIDE1-1,WIDE2-1

This will make the pocket tracker use the the full
power of the D700 and with courteous channel 
sharing AND with no interference or congestion
between the tracker and your mobile. Notice that
setting DCD to both is generally not a good idea
for normal operation because it will keep your 
normal posits from going out if you are using band
B. So that is why this should be in a PM all its 
own only used for digipeating the tracker.


This will cause your D700 to ALWAYS be ready at
any time to act as a temproary digipeater in support
of TEMPn-N routing. SUch as FieldDay.

The question is whether this is saved in APRS mode
or only in packet mode. And if you set it while in a
PM, can it be saved there too? I suspect this only
works in PACKET mode but that is fine for Field Day
or any other temporary net you want to set up.

You can use TEMP or WIDE1-1 to digipeat thorugh any
mobile that is in APRS mode and has APRS-MENU-DIGI ON.
And you can use TEMP7-7 as a path for Field Day
via any D700 that is in packet mode or any other time.

Once we all agree to this or some other arrangement,
lets get EVERYONE on board. We can easily 
send a MESSAGE to ALL D700 users by simply using
the GROUP MESSAGE function. All of the Kenwoods
come with the default MESSAGE group of KWD.

Until we get the word out, a good message might be

To: KWD: See new-N settings for D700. Google XXXXXXX

and after we get everyone to a consistent set, then for
special events where you need an instant net on 
a different freq for emergency or special comms then:

To: KWD: SPECIAL, pse support alt-net on 145.01 TNX

or any other uses.. But we need owners to be fully
awayre of the potential of their radios, how to set
them up, and how to use them. THus, I want us all to
debate the final settings for digipeating and agree and
then include it in the New-N pparadigm so that APRS
works consistently everywhere and is flexible and can
respond quickly to emergent needs.

de Wb4APR, Bob

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