Wavecom W-SPECTRA (Automatic Monitoring System) V1.1.0 - Manual (Page 205)

WAVECOM Monitoring System W-SPECTRA, W-SPEED Manual V1.1.0 Transmission Modes
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X.25 PLP encapsulation in a LAPB frame (Cisco “Internetworking Handbook”).
The GFI (General Format Identifier) field contains general information of the packet format, the LCI (Logi-
cal Channel Identifier) field contains information on the logical channel and the PTI (Packet Type Identifi-
er) field contains information on the PLP packet type.
The WAVECOM implementation of the X.25 decoder features some options that can be selected:
Options | Frame Format… offers the decoding of Basic, Extended or Super frames.
Options | Display Mode… offers the display of All Frames or Error free Frames.
Options | Display… selects the kind (RAW, FULLFRAME, DATA ONLY) of data which ar to be displayed
 RAW: The content of the frame is not decoded, only the byte values, starting with the address-
field, are displayed (hex being the best choice). In this way signals can be displayed which only to
some degree conform to the standard.
 FULL FRAME: This is the general case in which header data as well as user data are displayed.
User data ar displayed in the text window and frame and packet headers are displayed in the sta-
tus lines as well as in the text window.
 DATA ONLY: Frame and packet headers are displayed in the status lines. In the text window only
user data are displayed.
ZVEI-1
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.
Parameter Value
Frequency range VHF/UHF
Operation modes Analogue Selcal
Modulation FM, SUB Tone
Receiver settings FM, BW = 12 kHz
Input format(s) AF, IF
If 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 within +1/-1.5% of the nominal value.
For ZVEI modes having nominal tone durations of 70 ms, the duration of a single tone may vary ± 15 ms.
Decoding the selective calls is started by clicking on a system. If transmission and system selection con-
form, the call sign is displayed on the monitor. In the Options menu a Time Stamp function can be ena-
bled to add date and time to each call.
Tone Allocation
Digit Hz Digit Hz
0 2400 8 2000