Timewave DSP-232, Operating Manual

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Chapter 6 GPS Applications
to send short messages and bulletins. Using Ultimeter II weather information can also be shown on the
computerized maps.
Hardware Configurations
There are four different hardware configurations you can use when operating within an APRS system, each for a
different purpose:
1. A computer running APRS, a GPS receiver, a DSP-232, an APRS Adapter Cable (optional), and a radio:
This complete con-
figuration allows you to
track all users on the system
in your area (including
yourself), and send/receive
messages and bulletins.
Because only one computer
port is used, this
configuration is called
Hardware Single Port
mode. Using AEA’s APRS
Adapter Cable, you can
connect a GPS receiver and
a DSP-232 to a single COM
port on a computer running
APRS, see figure 6-2.
Without AEA’s APRS
Adapter Cable, the DSP-
232 and GPS receiver would need to be connected to separate COM ports. Having two COM ports free on most
computers is a luxury most us don’t have with all the Windows related equipment such as mice and other serial
peripherals. Mobile laptop computer users need the APRS Adapter Cable because most only have one COM port.
Note: You will need to have a DB25 to DB-9 Adapter for the AEA APRS adapter cable to connecto to the
DSP-232.
2. A computer running APRS software, any AEA TNC, and a radio (No GPS receiver):
Because the TNC and GPS receiver use separate computer COM ports (totalling 2), their configuration is called
Dual Port Mode. This configuration lets you track all users on the system with your location being entered
manually. This also lets you send and receive messages within APRS. All AEA TNCs can be part of a system such
as this. This configuration allows anyone with any AEA TNC who is running APRS software in their computer to
take part in this GPS technology. You don’t need a GPS receiver to pull down location information from the
satellites because you enter your position manually on the APRS computerized map, which in most cases is fine
because you are at your house which doesn’t (shouldn’t) move. The only time you really need a GPS receiver is
when you are operating packet while mobile because manually updating your position while mobile isn’t practical-
you need the GPS receiver to pull in those satellite location signals and update your position as you move.
3. A DSP-232, a GPS receiver, and a radio (No PC):
This trio allows you to transmit your location automatically to others in an APRS system without having a computer
in the vehicle. This is known as a Stand Alone Tracking Device because others can track your motion without you
having to run APRS or even have a computer. The firmware in the DSP-232 allows the TNC to parse the incoming
location information from the GPS receiver (without the use of a computer running APRS which usually does the
parsing) and then beacon the information over the ham bands.
Because the DSP-232 can work both as a stand alone tracking device and as a connected APRS component, this
TNC can be of aid in natural disaster situations, during public service events, and search and rescue missions,
among other things.
For example, in a marathon, a pace car, ambulances, and other support vehicles could each have a DSP-232 acting
as a Stand Alone Tracking Device. A coordinator can be in a centralized location using a DSP-232, radio, and an
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