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[aprssig] APRS legality

Robert Bruninga bruninga at usna.edu
Wed Jan 28 17:12:51 UTC 2009


> Yes, in this one, specific case of allowed 
> one-way communication, namely "Brief 
> transmissions necessary to establishing 
> two-way communications with other stations." 
> The intent is everything. In the other 
> allowed cases, intent matters not at all.

I disagree.  The annals of Amateur radio are full of documented
cases of illegal operations by curmudgeons that maliciously
occupy a frequency, maliciously transmit  CW practice,
maliciously call CQ, maliciously transmit all manner of
emissions that in themselves are legal, but obviously illegal in
their intent to interfere with the communications of others.  I
say -intent- has everything to do with the legality of
transmissions.  My sensitivity here is:

>> ... I disagree completely with your definition
>> that attempts to turn APRS into a lifeless 
>> one-way, lights-on-nobody-home, broadcast-for-
>> public consumption system, on which no one can 
>> find anyone to communicate with in real time.
> 
> My definition attempts to turn APRS into nothing, 
> my definition allows hams to use APRS for those 
> things that interest them. Sorry it isn't what 
> interests you, but APRS belongs to every ham now, 
> and every ham needs to be free to use those parts 
> of the Swiss Army knife that fit their own needs 
> and desires.

Yes, all applications that do not detract from others are
welcome.  We are not arguing the devices or stations, what we
are arguing is the definition of the APRS system.  I defined it
as a system designed for two-way exchange of information between
all participants.  You are trying to define it as a one-way
broadcast telemetry system.  We disagree completely!  APRS has a
national channel, a network and a protocol.  All three were
designed to optimize the distribution of information and two-way
communications between all participants in the net.  So as I
said before:

>> The legal way to use the system is to 
>> participate in the network as it was designed...
> 
> How can you cling to this idea that a network 
> is needed to make APRS legal in the US. 

Because without transmissions being intended for the other
participants, (as they are in a net) then by your own claims,
they are nothing more than blind one-way transmissions, which
are very strictly limited by the FCC in the rules.  It is not in
keeping with the general principles of ham radio to transmit
blindly on a shared net, so for the health of the network, we
need APRS operators to be sharing the experience and the channel
and able to react to the network situation and to each other.

> Show me one single place in the rules where 
> the word or even the concept of network 
> appears...

A net is a group of other licensed individuals participating in
a two-way information exchange.  The concept covers the
situation when you transmit to that group, since without it
according to your claims, then any transmission to a group would
be a violation of your rules where you claim any transmission
not directly to another licensed individual is a one-way
transmission.  It is not.  It is part of a two-way communication
just like any other APRS station transmission except for the few
examples of Telemetry also discussed here. (Unattended trackers,
WX stations or instruments).

> Again, it is a shame that the FCC felt 
> one-way was such an obvious concept 
> they did not define it. I maintain that 
> any transmission not directed at one or 
> more specific amateur stations as part of a  
> bidirectional exchange is one way. 

Great!  Finally we agree.  APRS is that bi-directional two-way
communication system, with individual operators "transmitting"
their information "directed at" the many other "specific amateur
stations" all participating in the bi-directional exchange on
the national APRS frequency called  APRS (the quotes are your
words).  We agree that there are some one-way examples also on
APRS as noted above, from unattended remote sensors.  But they
do not define APRS.  The one-way devices with transmistters-only
are a tiny minority.  The two-way network of stations using
-transceivers- is what defines APRS, and is the clear
distinction the FCC was trying to make.

> I did not say nets were bad, simply that 
> they have nothing to do with the rules. 
> Operating in a net or not, the same rules 
> apply.  Operating in a net does not free 
> you from a single requirement of the rules.

I agree completely here too.  And you notice that your words are
now allowing for NET's in  your statement above as "one-or more
specific stations", which is what I have claimed all along.
That is what we call a "net", and that is what makes APRS a
two-way system between stations.

>> Positions (or weather for that matter) 
>> of APRS operators participating in a net 
>> are no more telemetry than my saying "its
>> cold outside"[on the morning net].
> 
> Except they are one-way.

Nope, they are two-way, since they are transmitted by an
operator to "one-or more specific stations" who are
participating in the roundtable (net) as two-way stations. (We
agree that positions from unattended one-way trackers,  WX or
remote instruments are one-way, since they are not listening).

> Thank you. And so are home and mobile 
> stations who automatically transmit 
> their weather or position data. 

We disagree here.  If the station is both sending and receiving
on the APRS channel with all the other specific participants
(using your words), then it is two-way communications and not
the same as the one-way unattended transmit-only remote devices
that clearly fit the FCC definition of one-way transmissions. 

> If you don't say this, then a station that 
> transmits when no one is listening MUST be 
> violating the rules.  Can't you see it is 
> ridiculous to have legality determined by  
> who is listening???

Exactly!  That is why your interpretation is ridiculous.
You are saying that every one of my voice transmissions on the
morning 2 meter FM voice roundtable are one-way, because I am
not directing them specifically to a specified member of the
group.  I say that is absurd.  Those transmissions in such a net
are two-way, just like APRS transmissions are in a net and are
also two way (unless from a one-way device).

>> But I want to encourage the licensed 
>> operators of those [one-way] "trackers"
>> installed in a vehicle with a live 
>> human licensed radio operator on board 
>> to also have the means to be contacted 
>> and participate in the APRS network if 
>> by nothing else than including his voice
>> monitoring frequency in his position text.  
>> So that he can be a two-way participant 
>> in the APRS network.
> 
> Encourage whatever you want, but don't 
> disparage those who use APRS for functions 
> different than you want. APRS is open to 
> participation  of any licensed ham.

I try not to disparage those one-way trackers.  They have great
value in specific applications.  In fact, I have two remote
one-way telemetry sensors on the air myself.  I am *not* trying
to disparage those one-way trackers, but what I am trying to do
here is prevent you from disparaging all the other majority of
APRS operators as just a bunch of self-serving- one-way-
transmit-in-the-blind- for-internet-public-consumption system.

APRS is a two-way tactical real-time network for the exchange of
digital information between operators (which also allows the use
of some one-way telemetry devices as well).  Users may use it
how they see fit, but should consider the other users when they
join the net (ie, transmit). 

Hope that clarifies the distinction.
Bob, WB4APR




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