What Does EchoStation Do?
EchoStation is software that lets you
connect a personal computer to one or two radios, to create either a
repeater or an announcement machine. The program takes care of all
necessary functions, such as turning the transmitter on and off at appropriate times, and
sending a CW ID or
voice
ID periodically.
Repeater-control circuits typically use specialized hardware to perform
functions such as CW identification, tone generation, and timing. Since
EchoStation implements all of these functions within its software, no such
equipment is required. This makes EchoStation ideal for portable or
emergency set-ups, or for clubs who wish to use an existing PC to control their
repeater.
EchoStation uses your PC's built-in sound card to communicate with a
transceiver (or a separate transmitter and receiver), by receiving audio signals
from the receiver's speaker jack and sending audio signals to the
transmitter's microphone input.
The program can run in any of four different modes:
Duplex repeater
Simplex repeater
Simplex autopatch
Each of these modes is described below.
Announcement machine
An announcement machine plays any of several pre-recorded announcements at designated times.
It is most commonly used to announce club meetings, hamfest information,
news bulletins, etc. over an existing repeater. To prevent
interference, it "listens" before transmitting to be sure the frequency is not
already in use before beginning an announcement.
Note that EchoStation can run as a repeater and announcement machine at
the same time.
Duplex repeater
A duplex repeater (a conventional repeater) receives on one frequency and
transmits on another simultaneously. Anything received on one frequency is
immediately re-transmitted on the other. Of course, this setup requires a
separate transmitter and receiver, and some type of RF isolation to prevent the
transmitter from interfering with the receiver. EchoStation also allows a
telephone line to be connected, through a "voice modem", for autopatch
capability.
Simplex repeater
A simplex repeater receives and transmits on the same frequency, but at
different times. It picks up a signal on the receiver, begins "recording"
it, and after the signal finishes, it turns on the transmitter and "plays it
back". This can be accomplished using an ordinary transceiver and a single
antenna. However, it is generally only usable for short transmissions,
because there are long periods of silence between each one. This type of
repeater is usually used for portable or emergency set-ups.
Simplex autopatch
A simplex autopatch allows telephone calls to be placed or received over a
single radio frequency. In this mode, EchoStation connects to an FM
transceiver, and switches it rapidly between receive and transmit. A
station using the simplex autopatch sends touch-tone commands over the air to
begin and end each call, and during the call, the two parties take turns
speaking to each other.
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