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Download W74PC, W-PCIe, W-PCI, W-CLOUD and W-CODE
Transcript
The center frequency can be set to any value between 200 and 3400 Hz via the Center item in the Demodulator menu. The center frequency is nominally 800 Hz which is dictated by the quartz filters of professional receivers while other receivers work with 1000 Hz. The shift can be set between 100-300 Hz and controls the lock-in-range of the center frequency (bandwidth = 1.2 x shift). Using Options | Alphabet the output can be set to Latin, Cyrillic, Greek, Arabic or Hebrew. Using Options | AFC the continuous automatic tuning to the center frequency of the CW-Morse signal can be enabled or disabled. The software reports an error condition (ERROR) if the controlled parameters as the dot-dash ratio, the inter-word or inter-character breaks deviate too much from the standard, and error-free decoding cannot be maintained. DCS SELCAL DCS stands for Digital Coded Squelch (also known as DCSS, Digitally Coded Squelch Signaling), and is used for selective calls and remote control applications. Parameter Value Frequency range VHF Operation modes Digital Selcal Modulation FSK Symbol rate 133.7,134.4, 137 Bd Receiver settings FM, BW = 15kHz Input format(s) IF The data is transmitted on sub audible tones within the frequency range 2 Hz to 300 Hz. In practice, DCS is similar to CTCSS, but uses 104 octal 3-digit code words instead of continuous analogue tones. The data is sent as a series of 23-bit GOLAY encoded frames without any sync bits. Polarity can be normal or inverse, and must be selected by the user. DCS Code Table Normal Inverse Normal Inverse Normal Inverse Normal Inverse 023 047 155 731 325 526 516 432 025 244 156 265 331 465 523 246 026 464 162 503 332 455 526 325 031 627 165 251 343 532 532 343 032 051 172 036 346 612 546 132 036 172 174 074 351 243 565 703 043 445 205 263 356 212 606 631 047 023 212 356 364 131 612 346 051 032 223 134 365 125 624 632 053 452 225 122 371 734 627 031 054 413 226 411 411 226 631 606 065 271 243 351 412 143 632 624 071 306 244 025 413 054 654 743 072 245 245 072 423 315 662 466 WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0 Transmission Modes 153
