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The information in this publication is subject to improvement and change without notice. Although every effort is made to ensure the accuracy of the information in this manual, Broadcast Electronics accepts no responsibility for any errors or omissions. Broadcast Electronics reserves the right to modify and improve the design and specifications of the equipment in this manual without notice.
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Marti Electronics Product Warranty (One-Year Limited) Broadcast Electronics (BE) hereby warrants all new Marti Electronics branded products, including STL systems, manufactured by BE, against any defects in material or workmanship at the time of delivery thereof, or that develop under normal use within a period of one (1) year, from the date of shipment.
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Emergency and warranty replacement parts may be ordered from the following address. Be sure to include the equipment model number, serial number, part description, and part number. Non- emergency replacement parts may be ordered directly from the Broadcast Electronics stock room at the number shown below.
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All returned merchandise must be sent freight prepaid and properly insured by the customer. MODIFICATIONS - Broadcast Electronics, reserves the right to modify the design and specifications of the equipment in this manual without notice. Any modifications shall not adversely affect performance of the equipment so modified.
SR-30 / SR-40A RPU Receivers 1 Introduction The Marti SRPT-30 and SRPT-40A Transmitters with companion SR-30/SR-40A Receivers, form a high quality FM, synthesized, point-to-point, line of sight, radio communications link for remote broadcast applications. The SR-30 receiver is a dual channel unit that can be programmed on any 2 frequencies within a 50 MHz band.
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3. Ensure the receiver rear–panel ON/OFF switch is OFF. Connect the rear–panel AC line receptacle to an 85 to 264V, 47 to 63 Hz AC power source. USE ONLY A 3–PRONG GROUNDED OUTLET RECEPTACLE FOR SAFETY. The unit can also be operated from a +10V to +14V external dc supply. If DC operation is required, refer to Figure 1 and connect: 1) the positive wire to J4–7 and 2) ground to J4–8.
Mobile Repeater Connections A mobile repeater installation requires one of the following Receiver to Transmitter cables: For an RPT–15 Transmitter, use Cable No. 585–037–2 with 4 Amp fuse. For an SRPT–30/40A Transmitter, 12–15 VDC operation, use Cable No. 585–139. For SRPT–30/40A Transmitter, 15–30 VDC operation, use Cable No. 585–140. A mobile repeater installation also requires one of the following mobile mounting brackets: - For an SR–30/SR–40A receiver, use Mobile Mounting Bracket 700–252.
BASE STATION ANTENNA INSTALLATION CHECKLIST The following suggestions are offered to help those responsible for antenna installations avoid costly errors in assembly and adjustment. Marti Electronics, Inc. assumes no responsibility for the installation and performance of antenna systems associated with its equipment. The following suggestions are not intended to be a complete step–by–step procedure, simply a listing of some of the most frequently reported errors in antenna system installation.
4 OPERATION CONTROLS AND INDICATORS 4.1.1 SIGNAL ATTENUATION CONTROL The SIGNAL ATTENUATION control adjusts a variable attenuator at the input of the converter. This control is designed to minimize the reception of unwanted signals during interference conditions. These conditions are due to extremely high intermodulation from a combination of neighboring signal frequencies.
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4.1.4 MULTIMETER The SR–30/SR–40A is equipped with a multimeter. The multimeter is controlled by the meter select switch. The following text presents a description of the multimeter switch positions. To use the multimeter, operate the switch to the desired position and view the indication on the meter. The green values on each meter scale present nominal values.
INITIAL START–UP AND OPERATION The following text presents initial start–up and operating procedures. Apply power to the unit. The POWER indicator will illuminate. The AFC LOCK indicator will illuminate when the unit locks to a frequency. The UNSQUELCHED indicator will illuminate if the unit signal level is above the squelch point. The MAX SIG level indicator will illuminate if no attenuation is applied.
5 THEORY OF OPERATION Refer to block diagram 597–8104–2 in the SCHEMATIC AND ASSEMBLY DRAWINGS section as required for the following discussion. Converter, 913–2132–150/–240/–330/–450/–950 The received RF signal is applied to the converter circuit board. This circuit board is: 1) assembled for specific bands of operation and 2) can accept a 50 MHz (30 MHz for 950 MHz units) wide group of frequencies within the specific band.
Input/Output Filter, 800–193AD All input/output circuits connected to the accessory connector as well as the AC line input have radio– frequency filters. The filter circuitry is located on I/O Filter Schematic 800–193AD. Front Panel Circuit Board Assembly, 953–2130–001/–002 The front panel circuit board contains three switching power supply circuits, decode circuitry for the SR–40A frequency programming switches, the metering circuitry, and a digital–to–analog converter (DAC) circuit.
8 TUNE–UP AND ADJUSTMENTS NOTICE This equipment was thoroughly tested and inspected at the factory prior to shipment. Adjustments should rarely be necessary in the field and should only be attempted by highly trained technicians familiar with this type of equipment. Laboratory grade test equipment is required and is listed under TEST EQUIPMENT AND TOOLS.
1. Connect an RF signal from an encoded Marti transmitter adjusted for proper encode frequency and modulation level as an encode signal source to the receiver. 2. Operate the multimeter to DECODE LEVEL. 3. Adjust SENSITIVITY control R1 for approximately 2 volts p–p on the front panel meter. 4.
LEVEL PART NO. DESCRIPTION REF. DES. 9 SR 30 BILL OF MATERIAL This bill of material uses an indented structure to show relationships of parts into sub assemblies. Example; all BOM LEVEL 2 parts are contained in the BOM LEVEL 1 part immediately above it. PART NO.
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LEVEL PART NO. DESCRIPTION REF. DES..3 400-196 IC, SMT, 1.5A STEP-UP REGULATOR ..3 401-164 IC, SMT, 8-Bit Ser In, Par Out SR Phillips U5,U6 74HC164D ..3 401-165 IC, 8-Bit Ser/Par In, Ser Out SR Phillips U1,U2,U3,U4,U20 74HC165D ..3 401-275 IC,SMT,OP-AMP,LOW NOISE,HIGH U15,U16,U17,U18, AUDIO BW...
LEVEL PART NO. DESCRIPTION REF. DES. 10 SR 40A BILL OF MATERIAL This bill of material uses an indented structure to show relationships of parts into sub assemblies. Example; all BOM LEVEL 2 parts are contained in the BOM LEVEL 1 part immediately above it. PART NO.
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LEVEL PART NO. DESCRIPTION REF. DES..3 401-164 IC, SMT, 8-Bit Ser In, Par Out SR U5,U6 Phillips 74HC164D ..3 401-165 IC, 8-Bit Ser/Par In, Ser Out SR Phillips U1,U2,U3,U4,U20 74HC165D ..3 401-275 IC,SMT,OP-AMP,LOW NOISE,HIGH U15,U16,U17,U18, AUDIO BW ..3 401-374 IC, OCTAL D FLIP-FLOP W 3-ST OUT U7,U12 ..3...
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