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Motorola Gp328plus Gp338plus Gp338xls Detailed 6804112j28 G Manual
Motorola Gp328plus Gp338plus Gp338xls Detailed 6804112j28 G Manual
Here you can view all the pages of manual Motorola Gp328plus Gp338plus Gp338xls Detailed 6804112j28 G Manual. The Motorola manuals for Portable Radio are available online for free. You can easily download all the documents as PDF.
Page 101
Frequency Generation Circuitry5B-9 6.0 Frequency Generation Circuitry The Frequency Generation Circuitry is composed of two main ICs, the Fractional-N synthesizer (U201), and the VCO/Buffer IC (U241). Designed in conjunction to maximize compatibility, the two ICs provide many of the functions that normally would require additional circuitry. The synthesizer block diagram illustrates the interconnect and support circuitry used in the region. Refer to the relevant schematics for the reference...
Page 102
5B-10Frequency Generation Circuitry 6.1 Synthesizer (Refer to UHF Synthesizer Schematic Diagram on page 5B-23) The Fractional-N Synthesizer uses a 16.8MHz crystal (FL201) to provide a reference for the system. The LVFractN IC (U201) further divides this to 2.1MHz, 2.225MHz, and 2.4MHz as reference frequencies. Together with C206, C207, C208, R204 and CR203 , they build up the reference oscillator which is capable of 2.5ppm stability over temperatures of -30 to 85×C. It also provides 16.8MHz at pin...
Page 103
Frequency Generation Circuitry5B-11 6.2 VCO - Voltage Controlled Oscillator (Refer to UHF Voltage Controlled Oscillator Schematic Diagram on page 5B-24) Figure 5-5: VCO Block Diagram The VCOBIC (U241) in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U241 pin 19) determines which oscillator and buffer will be enabled. A sample of the RF signal from the enabled oscillator is routed from U241 pin 12, through a...
Page 104
5B-12Frequency Generation Circuitry The VCOBIC(U241) is operated at 4.54 V (VSF) and Fractional-N synthesizer (U201) at 3.3V. This difference in operating voltage requires a level shifter consisting of Q260 and Q261 on the TRB line. The operation logic is shown in Table 5-1. In the receive mode, U241 pin 19 is low or grounded. This activates the receive VCO by enabling the receive oscillator and the receive buffer of U241. The RF signal at U241 pin 8 is run through a matching network. The resulting...
Page 105
Notes For All Schematics and Circuit Boards 5C-13 7.0 Notes For All Schematics and Circuit Boards * Component is frequency sensitive. Refer to the Electrical Parts List for value and usage. 1.Unless otherwise stated, resistances are in Ohms (k = 1000), and capacitances are in picofarads (pF) or microfarads (µF). 2.DC voltages are measured from point indicated to chassis ground using a Motorola DC multime- ter or equivalent. Transmitter measurements should be made with a 1.2 µH choke in series with the...
Page 106
5C-14 Notes For All Schematics and Circuit Boards THIS PAGE INTENTIONALLY LEFT BLANK
Page 107
Circuit Board/Schematic Diagrams and Parts List5B-158.0 Circuit Board/Schematic Diagrams and Parts List 40 J2001 B503 3 FL201 TP201 C247 C251 C285C289 C370 C374C386 C248 C273 C286 C276 C253 C271 C272 L282 3 L2431 L273 3 L2531 L271 L321Q261 3 4 Q241R333R339 R243R248 R253R260 SH241 C210 C211 C212 C213 C214 C220 C230 C257C260 C294 C292C229 C203 C217 C235 C228 C233 C238 C297 C291 CR201 L201 L202L203 L232 Q210 3 4 Q260 3 4 R256R255 SH201 U247 B504 C522 FL301PB502 R352 VR441 C325 C324 C323 L311 R351 SH323C328...
Page 108
5B -16Circuit Board/Schematic Diagrams and Parts List 2 S502 35 4 1 2S501 C8 C 4J101 4 3 2 J102 C108 C132 C173 C172 CR105H101 P100 Q111 3 4 R101 R170 R133 R172 C315 C321 C395 C313 C310 C314 C318 C380 C306 C311 C316 C317C312 CR304 CR305CR303 L340 L306 L307 L305 L304 R306 R307R347 R305 SH302 C309 C307 L303 Q301 R304R303R340 R328 C383 C390 C346C339 C340 C341 C342C343 C357C358 R344 13 25 37 1U301 C337 C329 C347 C348 C356 L314 SH322 C336C344 C360C355C361C382 L331R343 R350 C345 C334 C359 C327C330 C326...
Page 109
Circuit Board/Schematic Diagrams and Parts List5B-17 ZMY0131016-O 40 J2001 B503 B504 FL201 13 4 6 SH201 TP201 C210 C211 C212 C213 C214C220 C230 C257C260 C292 C229 C203 C217 C235 C228 C233 C238 C297 C291 CR201 L201 L202 L203 L232 Q210 3 4 Q260 3 4R256R255U247 C294 C247 C251 C285C289 C370 C374 C386 C271 C272 C248 C273C286 C276 C253L282 3 L2431 L273 3 L2531 L271 L321 Q261 3 4 Q241R333R243R248 R253R260 R339 SH241C391 C328C397 C325 C522 C554 C324 C323 FL301 R351 L311PB502PB504 Q316 Q315 R326R334 R335...
Page 110
5B -18Circuit Board/Schematic Diagrams and Parts List ZMY0131017-O 2 S502 35 4 4C8 C S501 2 C108 CR160 J101 4 3 21 J102 R101 R170 CR103 P100 Q 111 3 4 C172 C132 C173 CR105 H101 R133R172R102 R130 R131C105 C309 C315 C321C395 C306 C311 C307 C310 C314 C318 C313C380 C316 C312 C317 CR304 CR305CR303 L340 L306 L307 L303 L305 L304 Q301 R306 R307R304 R303R347 R305 R340 R328SH302C337 C383C390 C329 C336 C344 C345 C346 C347 C348C334 C356C339 C340 C341 C342 C343 C357 C360 C355 C358 C359 C361 C382 L314 L331 R343 R350...