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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 171
Frequency Generation Circuitry5D-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 172
5D-10Frequency Generation Circuitry 6.1 Synthesizer (Refer to 330-400MHz Synthesizer Schematic Diagram on page 5D-24) 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...
Page 173
Frequency Generation Circuitry5D-11 6.2 VCO - Voltage Controlled Oscillator (Refer to 330-400MHz Voltage Controlled Oscillator Schematic Diagram on page 5D-25) 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,...
Page 174
5D-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 175
Notes For All Schematics and Circuit Boards 5D-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 176
5D-14 Notes For All Schematics and Circuit Boards THIS PAGE INTENTIONALLY LEFT BLANK
Page 177
Circuit Board/Schematic Diagrams and Parts List5D-158.0 Circuit Board/Schematic Diagrams and Parts List B503 B504 C216 FL2011 3 46 40 J2001 TP201 C247 C251 C285C289 C370 C374C386 C248 C273C286 C276 C253 C271 C272 L282 3 L2431 3 L2531 L271L273L321Q261 3 4 Q241R333R339 R243R248 R253R260 SH241TP202 TP302 C210 C211 C212 C213 C214C220 C230 C257C260 C294 C292C229 C282 C283 C203 C217 C235 C228 C233 C238 C297 C291 CR201 L201 L202L203 L232 Q210 3 4 Q260 3 4 R206 R256 R255 SH201 U247C328 C324 C325 C521 C323 C391...
Page 178
5D-16Circuit Board/Schematic Diagrams and Parts List 2 S502 35 44 C 8 C S501 2 C108 CR160 1 J101 4 3 2 J102 P100 C132 C173 C172 CR103 CR105 H101 M100Q111 3 4R101R170 R133 R172 C309 C315 C321 C395 C307 C310 C314C306 C311 C380 C312 C318 C313C317 C316 CR304 CR305CR303 L340 L304 L306 L307 L303 L305 Q301 R306 R307 R304 R303 R347 R305R328 R340SH302 C337 C383 C390 C329 C336 C344 C345 C346 C347 C348C334 C356C339 C340 C341 C342 C343 C357 C360 C355 C358C359 C361 C382 L314 L331R343 R350 R344SH322 13 25 37 1U301...
Page 179
Circuit Board/Schematic Diagrams and Parts List5D-17 ZMY0131018-O 40 J2001 B503 C216 C282 C283 C210 C211 C212 C213 C214C220 C230 C257C260C294 C292 C229 C203 C217 C235 C228 C233C297 C291 CR201 FL201 1 3 4 6 L201 L202L203 Q210 3 4 Q260 3 4 R206 R256R255 SH201 TP201 C238 L232 U247 B504TP202 TP302 C391 C328 C324 C325C521 C323 C397 FL301L311PB501 PB502 Q315 Q316 R326 R334 R335 R338R300 R314 R316 R318 R319 R325 R327 R351 R352 RT300 RT301 SH323 VR300 VR440 C381 C375 R310 C319 C320C322 L309L310 R308 R309...
Page 180
5D-18Circuit Board/Schematic Diagrams and Parts List ZMY0131019-O C539 C540 C541 C542 C543 C548 C525 C526 C527 C528 C529 C530 C531 C532 C533 C534 C535 C536 C537 C538 C544 C545 C546C547 C549 C550 C551 C552 C553C555 R509 R511R510 2 S502 3 54 4C8 C S501 2J101 4 3 21 J102 C108 CR103 CR160 Q 111 3 4R101 R170 P100C132 C173 C172 CR105H101 R133 R172 R130 R131 C311 C309 C315 C321 C395 C307 C310 C314C306C380 C312 C318 C316 C313C317 CR304 CR305 CR303 L340 L304 L306 L307 L303 L305 Q301 R306 R307R304 R303 R347...