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[aprssig] APRS legality

Robert Bruninga bruninga at usna.edu
Wed Jan 28 23:07:04 UTC 2009


<all the continuing paragraphs and endless repetition snipped>

> Bob,... I'd say over the last 12 years I've  
> transmitted somewhere over 100,000 packets 
> on HF and VHF APRS. Aside from a tiny handful 
> of messages (probably less than 0.001%), 
> none were directed at "one or more specific 
> stations".  They were one-way transmission 
> to whoever happened to be listening, and for reception  
> into the APRS Internet System.

Fine, that was your intent.

Similarly, I have probably transmitted 100,000 or so packets too
but the difference is that mine were all directed toward the
local APRS network and the specific partitipating stations.
None of mine (except the unattended remote telemetry station)
were one-way transmissions. 

> Two one-way transmissions do not make a 
> two-way transmission!

Agreed!  Because they are both one-way transmissions!  But my
APRS transmissions are not one-way transmissions with no
intended recepients as you claim.  My APRS station comunications
are two-way communications intended for a specific set of
recepients who are all participating in a two-way (multi-way)
net.

> Right now you and I are having a two way 
> conversation. No matter how much it  
> seems to others we are just screaming at 
> each other, each message is a reaction to 
> the other person's prior message.  If one 
> message from me was "today is wednesday", 
> and you sent "The sky is blue", are we 
> having a two way conversation? Of course 
> not, we are both sending random one-way thoughts.

We hear that all the time on ham radio.  Users are sharing their
often random thoughts with the group and a tit-for-tat is not
required by the FCC rules.  In the example above, and in this
email two-way exchange, we are talking apples and oranges, yet I
say it IS a two-way communications because there are two or more
of us talking at each other.  There is no requirement in the FCC
rules that requires comprehension or agreement by the other
station to make it 2-way. 

> You send your position every 30 minutes, 
> I send my weather every 10 minutes, Joe 
> sends his tide reading every 15 minutes. 
> Is this a three-way conversation, or 
> three one-way transmissions. To me, the 
> answer is obvious. 

Yes, it is obvious to me too.  It is a 2 or 3-way communications
on the APRS network. If they are sending these on the APRS
network using a transceiver that is also receivig this data,
then it is a multi-way communication between/among that group.
However, if the tide gage is connected to a transmitter only,
then it is a remote telemetry device and it is sending a one-way
transmission which we both agree is also legal under the FCC
rules.

> And yes, I know this isn't your "concept" 
> behind APRS (TM).  

Ah, but it is.  It's a two-way, or if you want to be specific,
it is a multi-way comunications network and of course it can
include the clearlly defined one-way telemetry devices as well
as all the other two-way exchanges. 

> This is however, the reality of 144.39. 
> Go ahead and encourage people to use 
> APRS more like your concept. Just please 
> do not say people do not have the legal 
> right, or the Bob-given right, to use the 
> way the majority use, and want to continue 
> to use, 144.39 and its associated APRS 
> (TM) tools.

Ah, I don't think I ever said any of that.  I welcome one-way
WX/tracker/etc telemetry devices for the applications they are
best at, but I also encourage every station with a transceiver
and/or an operator present to use the two-way aspects of his
APRS station to the advantage of all in his local net.  This
heated debate is from what appears to me to be your attempt to
force your concept of one-way transmission on everyone else.

And I disagree with your facts.  I contend that the vast
majority of APRS stations are two-way and that the remote
transmitter-only one-way telemetry devices are in the tiny
minority.
In my area, right now, I see 241 stations on local RF in the
DC/Baltimore area:
 - 56 are digi's     (2-way)
 - 44 are objects    (2-way)
 - 50 are home stns  (2 way)
 - 18 are home WX    (2-way)
 - 60 are D7/700/710 (2-way)
 -  2 are remote WX (1 way)
 -  4 are Mic-E's   (1-way)
 -  3 are NMEA      (1-way)
 -  4 are trackers  (1 way)

So lets make a deal.
I won't try to call your one-way transmit only telemetry devices
as two-way, if you won't try to force your definition of one-way
on all the rest of APRS stations that are two-way participants
in the network.

Bob, Wb4APR




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