APRS - Tool or Toy?
Automatic Packet Reporting System (APRS) is essentially a computer mapping program and terminal software combined, which
allows users to display real-time information on a computer screen via symbols and text using wireless transceivers.
This information can be transmitted by any one participant and viewed by any other person on the network or system
using a previously agreed upon radio frequency and the APRS soft ware along with a transceiver/receiver, TNC (wireless
modem) and a personal computer.
Global positioning systems can also be integrated into APRS to 'beacon' the users location to all other members of the
APRS 'net'. This provides 'cruise missile' accuracy of the reporting stations location. Examples of this tracking ability
include balloon launches, tracking of emergency support vehicles and personnel and participants in various sporting events
including marathons, boat races, bike rides, etc. Locations are either entered manually by the participant or net
controller based on map headings, or passively displayed with greater accuracy by GPS connected to the TNC with or without
a PC depending on the exact capabilities of the beaconing station.
Therefore everyone on a APRS system can be a information disseminator or an information user at the same time depending
on their situation and personal preference. APRS can be slaved to personal weather reporting stations allowing automated
reporting of local weather conditions including wind speed, direction, barometric pressure and rainfall. APRS can even
take National Weather Service data in the form of hourly surface observations (SA) data and display the information to
all users.
Does all this really provide something lacking in the weather/ham community or is it an interesting technological toy
seeking a reason to exist?
SKYWARN volunteers are entrusted with the task of "identifying, evaluating, and reporting dangerous weather". As
volunteers to the National Weather Service we are the ground based eyes to the NWS. Our information supplements the
technological assets of the WSR-88D Doppler radar and essentially provides a human calibration to a capable technological
resource. Along with the dedicated staff at the NWS a proven weather assessment triad is thus established.
As any tool which furthers these goals is a asset, and any tool which does not directly address the SKYWARN mission is
an impedance, we must cast a very critical eye on any tool be it APRS, or any other technology or procedure that is
currently available or forthcoming.
To end any further suspense the writer would vote a resounding NO to the perusal of APRS as any sort of "primary"
severe weather reporting tool. My opinion should be considered as a starting point for any APRS debate and not the
last word in considering APRS for severe weather identification, evaluation, and reporting.
Let us consider the following;
APRS's most critical weakness is the lack of the ability of a net controller to respond and determine the veracity
of any icon or text displayed on an APRS screen. Anyone can put anything on the map and not be interrogated by voice
as to the exact reasoning behind the report.
Tornado, hail, and severe rainfall symbols can be placed on the PARS map and set into motion by anyone, but no longer
maintained, therefore creating spurious weather events of an undefined origin, duration, and magnitude.
Voice communications are a two way event that offer the fastest and most concise depiction of rapidly changing events.
In a severe weather situation "speed is life". Anyone with severe weather training can participate in a severe weather
net, recognition of the originator can usually be confirmed by net control, or other hams, were as an APRS report will
be displayed, but remain difficult to confirm or interrogate.
APRS mapping to provide an overview of events seems irrelevant considering the ability of Doppler radar and the ability
of the NWS and it's amateur net controller's to provide real-time information to the spotter community.
A handy talkie/cell phone/land line, some training and two eyes looking at the sky are the minimum requirements for
SKYWARN spotting. A combination of transceiver, laptop PC, TNC and GPS can cost $1,000 to $2,000 and will be slaved
to only satisfying APRS hardware and communications requirements and provide no voice communications.
Can someone in their car or home managing an APRS station really keep their attention on the weather spotting or just
dealing with the protocol of APRS?
For $100 to $150 a LCD mini television will give me a live Doppler radar from commercial TV stations, in real-time,
in my car, during significant weather events without tying up any of my communications resources. A $39 pocket weather
alert radio can INSTANTLY alert me to watches and warnings. Can APRS do this?
When the fur starts flying in a severe weather situation, would you rather have a trained observer on voice frequencies
relaying information to the NWS or a pleasant looking icon on APRS being relayed to a minority of computer/ham radio
enthusiasts?
Conclusions
The best use of APRS to the spotter community, in my opinion, is if it could take real-time NWS Doppler radar data
and text warning messages and relay it to spotters mobile in the field or at their homes. Baring this eventuality,
this writer will "sit this one out" and wait for the mission and the technology of APRS to catch up with the real
needs of the SKYWARN community.
Currently APRS seems to be a interesting and rather fun technological adjunct to packet radio operations. Tracking of
moving vehicles or personnel seems to be its strong point and may have some relevance for public service activities.
Many ARES groups use packet for transmission of discrete or sensitive data, but again APRS would be an adjunct and not
a necessity.
Let this not be a condemnation of APRS, but the start of a serious discourse of weather spotting priorities and the
evolution of APRS to further the goals of severe weather identification, evaluation, and reporting.
73 Bernie Kopp KB9KEF
Milwaukee Area Skywarn Association
Milwaukee/Waukesha A.R.E.S.
E-Mail: bkopp@execpc.com
2-meter FM Voice 146.910- 127.3 PL Milwaukee Repeater Club (Wx Net)
146.670- 127.3 PL Milw./Waukesha A.R.E.S. (Wx Net)
