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2.3.7
The loudspeaker
The modem has a loudspeaker which may be used to listen to
what is happening when we call. The manufacturer's volume
setting is «lown.
Let us go through the stages of what happens when you make
your first attempt, and which we are now prepared to do. (The
following illustrates an example of a person in Norway calling
Semaforum BBS. The procedure will be very similar in your own
country).
When you dial Semaforum BBS, the first thing you hear is that
the modem lifts the receiver. After a second or so you will hear
the dialling tone. Thereafter you will hear the number being
dialled, - irregular tones with tone signals or clicking with impulse
connections.
The dialling tone ceases the moment the modem commences to
send the number and you will now hear a new signal. This is a
special call-up tone (1300 Hz) which is used to inform the
modem at Semaforum that this will be a data transmission. In
addition you may hear other background noises. These occur
when the telephone line is being routed to the number you
dialled.
When the line is connected, you will hear the telephone calling
at the remote apparatus. Let us assume that you don't get the
busy signal and that the modem at Semaforum BBS is
connected up to the line. You will now hear a high-level peeping
lasting about 3 seconds. This is the answer tone from the
bulletin board modem. This is followed by a new tone, the
remote modem's carrier wave.
Your modem will now sense its carrier wave . The connection
will now be established. It sounds as though the transmission
tone has been stifled. The status message CONNECT appears
on the screen.
The modem is now in modem status. Everything now entered at
the keyboard will be transmitted to Semaforum BBS.
This will be the situation, in a
little while. But first, some small
tasks are required to be carried out.
LZTR104006 R1.00
Zat 14.4/14.4-7 and Zat 19.2/19.2-7
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