[aprssig] Repeater Frequency Objects +

Robert Bruninga bruninga at usna.edu
Wed Apr 9 13:25:50 EDT 2008

This issue was discussed over on the Uidigi list, but it is now
resolved and so I am bringing it to the APRSSIG for general

The Question was the problem with the "+" symbol in repeater
frequency object names.  These objects appear to be lost to
FINDU, even though they are in the system.  You can see the
problem by looking at all of the 147.XXX repeater objects.  See

Click on one that has a + in the name, and a position map
display is not available.  But click on one without it, and it
works just fine.  The problem is that these object names are
passed from one routine to the other as URL's and URL's cannot
have a + in them.  Although this could be fixed by special code
in every such URL, FINDU has dozens of routines and is not going
to be able to fix this.

Therefore, I have changed all my docs and recommendations to
include this info.  Meaning, that + works OK on local RF where
the objects are most valuable, but that if the digi sysop wants
to see these objects via FINDU, then it is not a good idea to
use  a "+" in the object name.

But it is simple to work around.  In any of these URL's simply
type the WILDCARD (*) character in place of the "+" and it will
usually work.  For example.  My object is "147.105+D", which
cannot be found on FINDU.  BUT, if I ask for "147.105*D" then it
is found and plots just fine.

The only problem to this I see is that using the wild card,
might also find these repeater objects:  "147.105SD" or
"147.105ND" or "147.105-D"... I cant find any to test this

Anyway, lets get all those local repeater objects on the air.
Se how:

Bob, Wb4APR

> Recently, I have been asking our local digi
> owners to beacon locally (no hops) the 
> Skywarn frequency that covers the area. 
> An example of the Beacon Text is 
> !4636.23NS09417.79W#PHG5310/Skywarn   Crosslake 147.03+   
> Beacon set to every 10 minutes (local only)

Yes, please do!  This is part of the APRS LOCAL-INFO initiative.
But actually, there are much better formats.  The problems with
the above format are 

1) people do not see the freq unless they go look for it.
2) It only shows up under the DIGI's call
3) The freq will not show up on any D7 screens
4) The new D710's will not be able to one-button QSY

Please see the web page:
Which recommends a format something like this:

;147.03+SW*111111z4636.23N/09417.79Wr T107 R20m Net T 9pm

Will show up on the front panel of all mobile APRS radios as
" T107 R20m
" Net T 9pm   
" Skywarn

The benefits of this format are:
1) Can have a different position than the DIGI sending it
2) Shows on all APRS systems as an 147.03+SW object
3) Shows the PL tone (T107) (or Toff if no tone is used)
4) Shows the useable Range of the repeater (R20m)
5) Shows weekly net times
6) Shows as a Repeater Object
7) Flashes this info on the screen every 10 minutes locally only
8) Any D710 owner can automatically QSY to this frequency by
simply pressing the front panel "TUNE" button.  This will tune
the radio and set the PL for instant QSO.

These formats have been hammered out over the last few years and
work very well. Follow the TXXX format exactly. Do not include
tenths of a Hz.  Estimate the radio range in miles (in the USA)
or km elsewhere (R30k).  

The "SW" was chosen to make this 147.03+SW APRS object unique in
the world.  Check http://map.findu.com/147.03* to see what other
such objects have already chosen as their modifying characters
and choose ones that are unique.

Please spread the word.  EVERY APRS digi should be beaconing ONE
of these frequency objects to all users in its immediate SIMPLEX
range.  Normally, the intent of this FREQUENCY OBJECT is to
announce the *single*most*recommended*voice*repeater for
visitors and travelers in that immediate area.  If that is also
the skywarn frequency, then that is good.

But if the skywarn channel is a normally dead repeater with a
low probablity of users most of the time, then that is not
usually a good "most-recommended" repeater for visitors and
travelers.  Of course, this is purely a local option, and so the
digi owner will do what he thinks best.  But even in a highly
active skywarn area, if another voice repeater (not the skywarn
one) is the most commonly used, then I would still vote for
listing the most common repeater, because that is where the
traveler can find SOMEONE to talk to.  And there he can ask what
the skywarn frequency is.

The locals all already know what the skywarn freq is.  They
don't need the frequency beacon.  But it is the clueless
traveler, visitor, or occasionaly operator that may need this
Frequency Object to help him make contact and get local info.

Good luck.  This Local Info initiative is sweeping APRS and is
very powerful at getting more people involved in APRS by
providing more real-time, local info of immediate use.

Spread the word, far and wide. 


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