Wavecom W40PC, Руководство пользователя

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Glossary of Terms WAVECOM Decoders v6.15 W40PC, W41PC, W51PC
SELCAL
Selective call systems are an efficient supplement to voice traffic. One method was the so-
called single-tone-mode using five different tone frequencies, another one the two-tone-modes,
where the call number is transmitted as frequency combinations.
Developments led to the five-tone-sequence systems. The five digits are often divided into two
groups. The first digits work as radio net flags, the last three digits are user call numbers.
The entire call number is transmitted by consecutive tones in decade sequence. When two
identical digits are to be transmitted consecutively, then an eleventh frequency is used as a
repetition identifier. If there more than two identical digits are to be transmitted the repetition
tone is appended to the digit tone (e.g. 22222 is transmitted as f2 fw f2 fw f2, where f2 is the
tone for “2” and fw is the repetition tone).
In most systems the accuracy of the single frequencies has to be 1/-1.5% of the
nominal value.
Modifications of the tone allocation and tone duration has led to numerous systems despite
many standards.
Only the EURO (EuroSignal) system uses six consecutive tones. The worldwide telephone
signaling standard DTMF mode transmits two simultaneous tones.
Server
See file server.
Shift
The difference between two tones in a FSK transmission
shoc RSM
Software and database to control receivers and decoders produced by shoc Inc, R.Haenggi
Size control
A screen element found on WINDOWS that allows you to change the window size.
Space
Application Condition Condition
Voltage to signal ground Negative (-) Positive (+)
Conventional term MARK SPACE
Binary digit value 1 0
Timing signal state Off On
FSK signal state Lower frequency Higher frequency
Spinner
A control that allows you to increment or decrement numbers either by typing the numbers or
clicking the UP and DOWN arrow keys.
String
An item of information consisting of a sequence of text characters.