Service Manual
UHF1 (400-470MHz) Information
35
7.2.2
Receiver Back-end
Figure 7-3 Diagram of IF Processor
The first IF signal (73.35MHz) output by the IF amplifier goes into AD9864 (U401) via Pin 47, where the
signal is converted to the second IF signal (2.25MHz). Then the signal is converted to digital signal via
ADC sampling, and output via the SSI interface. Finally, the digital signal is sent to DSP (OMAP5912) for
demodulation.
AD9864 employs reference frequency of 19.2MHz and shares the crystal with the OMAP. The second
LO VCO comprises an oscillator, a varactor and some other components, to provide the 71.1/75.6MHz
LO signal. The 18MHz clock frequency is generated by the LC resonance loop.
7.3
Frequency Generation Unit (FGU)
The FGU is composed of VCO and PLL. It is the core module of the whole TX-RX system. This circuit
provides accurate carrier frequency during transmission, and stable LO signal during reception. It has a
direct influence on the performance of the system.
Summary of Contents for PD70X Series
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Page 49: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G PCB View Main Board Bottom Layer 39 ...
Page 50: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Top Layer 40 ...
Page 51: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Bottom Layer 41 ...
Page 52: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Top Layer 42 ...
Page 53: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Bottom Layer 43 ...
Page 54: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Top Layer 44 ...
Page 55: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Bottom Layer 45 ...
Page 57: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G Block Diagram Baseband Section 47 ...
Page 127: ...Service Manual UHF1 400 470MHz Information 117 Transmitter Circuit ...
Page 138: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G PCB View Main Board Bottom Layer 128 ...
Page 139: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Top Layer 129 ...
Page 140: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Bottom Layer 130 ...
Page 141: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Top Layer 131 ...
Page 142: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Bottom Layer 132 ...
Page 143: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Top Layer 133 ...
Page 144: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Bottom Layer 134 ...
Page 146: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G Block Diagram Baseband Section 136 ...
Page 217: ...Service Manual UHF2 450 520MHz Information 207 Transmitter Circuit ...
Page 228: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G PCB View Main Board Bottom Layer 218 ...
Page 229: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Top Layer 219 ...
Page 230: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Bottom Layer 220 ...
Page 231: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Top Layer 221 ...
Page 232: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Bottom Layer 222 ...
Page 233: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Top Layer 223 ...
Page 234: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Bottom Layer 224 ...
Page 236: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G Block Diagram Baseband Section 226 ...
Page 307: ...Service Manual UHF3 350 400MHz Information 297 Transmitter Circuit ...
Page 318: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G PCB View Main Board Bottom Layer 308 ...
Page 319: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Top Layer 309 ...
Page 320: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Bottom Layer 310 ...
Page 321: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Top Layer 311 ...
Page 322: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Bottom Layer 312 ...
Page 323: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Top Layer 313 ...
Page 324: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Bottom Layer 314 ...
Page 326: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G Block Diagram Baseband Section 316 ...
Page 401: ...Service Manual UHF5 806 941MHz Information 391 Transmitter Circuit ...
Page 413: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G PCB View Main Board Bottom Layer 403 ...
Page 414: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Top Layer 404 ...
Page 415: ...PD70X PD70XG HD705 HD705G PCB View Channel Board Bottom Layer 405 ...
Page 416: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Top Layer 406 ...
Page 417: ...PD78X PD78XG HD785 HD785G PCB View Channel Board Bottom Layer 407 ...
Page 418: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Top Layer 408 ...
Page 419: ...PD78X PD78XG HD785 HD785G PCB View Keyboard Bottom Layer 409 ...
Page 421: ...PD70X PD70XG PD78X PD78XG HD705 HD705G HD785 HD785G Block Diagram Baseband Section 411 ...
Page 494: ...VHF 136 174MHz Information Service Manual 484 Transmitter Circuit ...