Motorola Gm328 Gm338 Gm398 Detailed 6804112j18 E Manual
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Computer Software Copyrights The Motorola products described in this manual may include copyrighted Motorola computer programs stored in semiconductor memories or other media. Laws in the United States and other countries preserve for Motorola certain exclusive rights for copyrighted computer programs, including the exclusive right to copy or reproduce in any form, the copyrighted computer program. Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in...
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i Table of Contents Section 1 Model Chart and Technical Specifications 1.0 GM328/GM338/GM398 Model Chart ................................................................... 1-1 2.0 Technical Specifications ...................................................................................... 1-2 Section 2 Theory of Operation 1.0 Introduction .......................................................................................................... 2-1 2.0 VHF (136-174 MHz)...
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ii Section 4 VHF PCBs/Schematics/Parts Lists 1.0 Allocation of Schematics and Circuit Boards ....................................................... 4-1 1.1 Controller Circuits ........................................................................................... 4-1 2.0 VHF 1-25W PCBs / Schematics / Parts Lists ...................................................... 4-3 VHF (136-174 MHz) 1-25W 8486172B06 Top Side .............................................. 4-3 VHF (136-174 MHz) 1-25W 8486172B06...
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1-1 Section 1 MODEL CHART AND TECHNICAL SPECIFICATIONS 1.0 GM328/GM338/GM398 Model Chart GM Series, VHF 136-174 MHz Model Description AZM25KHC9AA1GM328 136-174 MHz 1-25W AZM25KHF9AA5 GM338 136-174 MHz 1-25W AZM25KHN9AA8GM398 136-174 MHz 1-25W Item Description X GCN6112_ GM328 Control Head Direct Mount XGCN6114_GM338 Control Head Direct Mount X GCN6115_ GM398 Control Head Direct Mount XXIMUD6010_Tanapa WM 136-174 MHz 1-25W X IMUD6023_ Tanapa WM 136-174 MHz 1-25W XXXRAD4198_BNC 136-144 MHz, 1/4 Wave Roof...
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1-2Technical Specifications 2.0 Technical Specifications Data is specified for +25°C unless otherwise stated. General Specifications Channel Capacity GM328 GM338 GM398 4 128 160 Power Supply 13.2Vdc (10.8 - 15.6Vdc) Dimensions: H x W x D (mm) Depth excluding knobsGM328 56mm x 176mm x 177mm (add 8mm for Volume Knob) Dimensions: H x W x D (mm) Depth excluding knobsGM338 59mm x 179mm x 186mm (1 - 25W) 59mm x 179mm x 198mm (25 - 45W) (add 9mm for Volume Knob) Dimensions: H x W x D (mm) Depth excluding...
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Technical Specifications1-3 *Availability subject to the laws and regulations of individual countries.Transmitter VHF *Frequencies - Full BandsplitVHF 136-174 MHz Channel Spacing12.5/20/25 kHz Frequency Stability (-30°C to +60°C, +25° Ref.)±2.5 ppm Power 1-25W Modulation Limiting ±2.5 @ 12.5 kHz ±4.0 @ 20 kHz ±5.0 @ 25 kHz FM Hum & Noise-40 dB @ 12.5kHz -45 dB @ 20/25kHz Conducted/Radiated Emission (ETS)-36 dBm 1 GHz Adjacent Channel Power-60 dB @ 12.5 kHz -70 dB @ 25 kHz Audio Response (300 -...
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2-1 Section 2 THEORY OF OPERATION 1.0 Introduction This Chapter provides a detailed theory of operation for the VHF circuits in the radio. For details of the theory of operation and troubleshooting for the the associated Controller circuits refer to the Controller Section of this manual. 2.0 VHF (136-174 MHz) Receiver 2.1 Receiver Front-End The receiver is able to cover the VHF range from 136 to 174 MHz. It consists of four major blocks: front-end bandpass filters and pre-amplifier, first mixer,...
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2-2VHF (136-174 MHz) Receiver There are two 2-pole 44.85 MHz crystal filters in the high-IF section and 2 pairs of 455 kHz ceramic filters in the low-IF section to provide the required adjacent channel selectivity. The correct pair of ceramic filters for 12.5 or 25kHz channel spacing is selected via control line BWSELECT. The second IF at 455 kHz is mixed, amplified and demodulated in the IF IC. The processing of the demodulated audio signal is performed by an audio processing IC located in the...