LA VHF: 29 - 50 MHz
SVR-200 Service Manual SVR-200 Vehicular Repeater This manual is intended for use by qualified technicians and includes all necessary information pertaining to the SVR-200 operation, circuit design and maintenance. Changes that occur after date of printing will be incorporated in supplemental service publications.
SVR-200 Service Manual Foreword Scope of this manual This manual contains the specifications, functional description, operating instructions, schematic, parts locator and parts list for the SVR-200 synthesized vehicular repeater. This manual is intended for use by qualified service technicians to aid them with installation, interfacing, alignment and trouble shooting of the SVR-200 when used with other land mobile radios.
SVR-200 Service Manual Specifications Transmitter: VHF Frequency Range: Rf power out: Spurious emissions: Freq stability -30°~+60°C: Modulation: Hum and Noise: Audio response (300-3kHz): Audio distortion: Local mic sensitivity: FCC Type Acceptance: Industry Canada Approval: 29-50 MHz (29-44 MHz and 36-50 MHz) 250mW - 2W -50dBc 15 PPM 20K0F3E -40 Flat or +6dB/octave <3% @ 60% deviation 300mV-5VPP LRUSVR-200LA 2390 XXX XXX Receiver: Frequency Range: RF sensitivity: Squelch sensitivity: Modulation accepta
SVR-200 Service Manual Functional Description Generally, vehicular repeaters are used as mobile extenders in cross-band operation: the link is VHF Low Band simplex and the mobile is Lo-band, VHF, UHF or trunking. In-band operation is possible, but care must be taken to prevent interference between the mobile's higher power transmitter and the repeater receiver. Proper frequency selection and antenna placement are important even in cross-band operation, but especially for inband use.
SVR-200 Service Manual If another unit were to arrive from a different scene and it is still the active priority, there will be two active repeaters on the air when a condition to repeat exists. When one of the SVR-200s unkeys to check for handheld activity, it will detect the presence of the other active SVR-200 and increment it’s priority counter and cease transmission. This is the self clearing mode to prevent radio collisions.
SVR-200 Service Manual Installation Before installing the SVR-200, ensure that the RF and repeater sections are properly aligned per the tuning instructions on pages 8-14 of this manual. Additionally, ensure that the SVR-200 jumpers are properly configured for use with the particular mobile radio that it will be connected to: J1 Controls the maximum drive level of the transmit audio output to the mobile radio. If J1 is installed, output amp U1B will have an adjustment range of 0-100 mVPP.
SVR-200 Service Manual Pin 3: Remote enable/disable. Connect to the radio's auxiliary output or a separate switch to remotely enable or disable the repeater. If this line goes high to activate the repeater, ensure that JP1 is set to the “+” position. If this line goes to ground, set JP1 to the “-” position. J8 has two positions to add a pull up (+) or pull down (-) resistor to this line if used with an open collector or dry contact output. Pin 4: Mobile PTT output.
SVR-200 Service Manual Alignment Before aligning the SVR-200, ensure that the mobile radio is aligned per the manufacturer’s service procedure; Ensure that the SVR-200 is properly programmed and the jumpers are set per the previous section. In order to properly align the SVR-200, you will need two service monitors and the mobile radio that the repeater will be installed with. Refer to figure 1 for alignment points.
SVR-200 Service Manual Receiver 1. Receiver IF: Connect a DC voltmeter to TP1 on the SVR-200 main board. Set the service monitor connected to the SVR-200 to the generate mode, receive frequency with a 1kHz tone and 60% deviation. Adjust the RF output of the monitor for a 1VDC reading at TP1. Adjust T1 and T2 on the RF board for a maximum reading at TP1. 2. Repeater squelch: Adjust the service monitor RF output for .5µV. Adjust RV9 on the SVR-200 main board so the repeater COR LED is just on.
SVR-200 Service Manual Communications Monitor A Mobile Radio Communications Monitor B Interface Cable SVR-200 Figure 4 Page 10
SVR-200 Service Manual Programming Using the Software The SVRCPS personalization software is used to program the SVR-200 for all of the operating parameters and options. The software is compatible with Windows 2000 and later operating systems The software is menu driven and on-line help is available at any time by clicking the left mouse button on the HELP icon on the right side of the tool bar.
SVR-200 Service Manual Mobile COR polarity: Determines if the COR signal from the mobile is active high or active low. Radio Type: Select either conventional or trunking. If a trunking mobile is selected, the SVR-200 will go through the voice channel acquisition procedure during portable-to-base repeat mode. On-air polarity: Select either active high or active low. This line is used to monitor the local mobile PTT for local mic repeat on conventional radios.
SVR-200 Service Manual Theory of Operation Receiver: The receiver is a double-conversion superheterodyne type, designed for narrow band FM reception. The first local oscillator is derived from the frequency synthesizer. The second LO is crystal controlled. RF Stage: The incoming RF signal from the antenna jack is directed to the first RF bandpass filter to improve selectivity and then to the input of the RF amplifier. The output of the RF amplifier is then presented to a second bandpass filter.
SVR-200 Service Manual Receive audio path: Receiver audio from the transceiver module is input on P2 pin 13 and presented to U5 pin 10 and pin 16. Pin 10 is the input of the receiver highpass filter to remove any sub-audible signals before being output on pin 11 and sent to U4 for receiver audio processing. Pin 16 is the input to the sub-audible tone decoder section of U5. Receive audio entering pin 7 of U4 is processed as flat, or -6db/octave depending upon PC programming.
SVR-200 Service Manual P1.5 Serial clock line output. Serial data that is sent to the PLL, the E²PROM and the audio processor chips are clocked by each low-high-low transition on this line. P1.6 Serial data output. Data sent to U10, U4 and U5 are output on this line and clocked by P1.5. P1.7 Data input to the microprocessor. Serial data is read from U10 (E²PROM) and U5 (sub-audio processor) on this line. P2.0 Lock tone output.
SVR-200 Service Manual T0 Test input, active low. Shorting J3 puts the microprocessor into test mode for alignment purposes. If shorted at power up, the receiver will operate open squelch mode and audio will be heard at the local speaker port regardless of carrier or tone input to the receiver. Although alignment is normally done with the RSSI output at TP1, a Sinad reading can be obtained using this mode of the test input.
SVR-200 Service Manual Notes This Page Intentionally left blank Page 17
SVR-200 Service Manual Parts List Reference Description Part # C1,C5,C6,C9,C10,C12,C15,C18,C35,C37 ......................... .1µFd chip capacitor ............................ 1010-03-5104 C2 ..................................................................................... 22µFd 16V tantalum chip capacitor ..... 1610-25-6226 C3,C27 .............................................................................. .047µFd chip capacitor ........................ 1010-03-5473 C7,C8,C13,C41 .................
SVR-200 Service Manual R50,R77-R80 .................................................................... 15K chip resistor ................................. 2010-03-5153 R54-R62,R64 .................................................................... 330 Ohm chip resistor ......................... 2010-03-5331 R68,R69 ............................................................................ 4.7K chip resistor ................................ 2010-03-5472 R43 ...............................................
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5 4 3 2 1 RxAudio RSSI RX5V R1 100K R2 270 L18 .01 C25 4p S-227-5008 C21 R8 100 C22 15p HPF C1 270p C2 68p C3 68p LPF C4 220p L6 270nH L5 220nH L7 220nH C14 560p C15 C16 68p 100p C11 47p C9 47p 10K L23 180nH 100p 120nH C17 100p C12 82p L17 3.
