Instruction/ maintenance manual of the product SR560 SRS Labs
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MODEL SR560 LOW-NOISE PR EAM PLIFI ER 1290-D Reamw ood Av enue Sunnyv ale, CA 94 089 U .S.A. (408) 7 44-9040 Copyr ight © 1989, 199 0, 1997, 1 999 Stanford Res earch Systems All Rights Reserved .
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TABLE OF CONTENTS i Introduction and Setup Instrument Overview 1 Preparation for Use 2 Line Voltage 2 Line Fuse 2 Line Cord 2 Ventilation 2 Power-Up 2 Repackaging for Shipment 3 Use in Biomedical Appl.
TABLE OF CONTENTS ii Calibration and Repair Offset Adjustment 17 Calibration 17 Front End Replacement 17 SR560 Offset Adjustment Procedure 18 Battery Replacement 18 Fuse Replacement 18 Noise Contours .
INTRODUCTION AND SETUP 1 Figure 1: SR560 Block Diagram INSTRUMENT OVERVIEW The SR560 architecture is diagrammed above. The instrument provides DC- coupled low-noise amplification of single- ended and true differential input signals at gains of 1 to 50,000.
INTRODUCTION AND SETUP 2 independent operation. Rear panel banana jacks provide access to the internal regulated power supplies (or batteries) for use as a bias source.
INTRODUCTION AND SETUP 3 ROLLOFF bypassed HIGH-PASS 0.03 Hz, +6 dB/oct LOW-PASS 1 MHz, -6 dB/oct GAIN MODE High Dynamic Reserve GAIN 20, calibrated LISTEN ON DEVICE ADDRESS As per SW601 Repackaging for Shipment The original packing materials should be saved for reshipment of the SR560.
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SPECIFICATIONS 5 SR560 LOW-NOISE PREAMPLIFIER SPECIFICATIONS CHART Inputs Single-ended or true differential Impedance 100 M Ω + 25 pF, DC-coupled Maximum Inputs 1 VDC before overload; 3 V peak to pe.
SPECIFICATIONS 6.
OPERATION AND CONTROLS 7 Figure 2: SR560 Front Panel FRONT PANEL OPER ATING SUMMARY The operation of the SR560 Low-Noise Preamplifier has been designed to be as simple as possible. The effect of each keypress on the front panel is reflected in the change of a nearby LED.
OPERATION AND CONTROLS 8 common with chassis ground by connecting the "AMP GROUND" and "CHASSIS GROUND" banana jacks on the rear panel of the SR560. When connected to AC power, the chassis of the unit is always connected to the grounding conductor of the AC power cord.
OPERATION AND CONTROLS 9 information on using filters with the amplifier in AC coupled mode. Gain Mode The allocation of gain throughout the instrument is set using the GAIN MODE pushbutton The Gain Mode is displayed by two indicator LED’s: HIGH DYNAMIC RESERVE and LOW NOISE.
OPERATION AND CONTROLS 10 Figure 3: SR560 Rear Panel REAR PANEL OPERATING SUMMARY The SR560 rear panel is pictured in Figure 3. Various interface and power connectors are provided, along with fuses and charger status LEDs. AC Power Input The power entry module contains the receptacle for the AC line cord and fuse.
OPERATION AND CONTROLS 11 turn off and the yellow "MAINTAIN" LED will be on full brightness. Blanking Input The blanking input accepts a TTL-level signal and grounds the amplifier signal path after the front end for as long as the input is held high.
OPERATION AND CONTROLS 12 • AVOID DEEP DISCHARGE Recharge the batteries after each use. The two-step fast-charge / trickle-charge operation of the SR560 allows the charger to be left on indefinitely. ALWAYS recharge the batteries immediately after the BATT indicator LED on the SR560 turns red.
CIRCUIT DESCRIPTION 13 DIFFERENTIAL LOW-NOISE FRONT END Two high-impedance inputs A and B allow the instrument to operate in either single- ended or true differential modes. Relays K103 and K104 allow the inputs A and B to be individually grounded, while K101 selects AC or DC coupling.
CIRCUIT DESCRIPTION 14 adjustment is provided by this stage. U405B, half of an AD7528 dual 8-bit DAC is used to provide a ±5 volt offset voltage at the non-inverting input of U402. The front panel offset control also sums at this junction, and provides an offset voltage of ±5 V that is buffered by U407D.
CIRCUIT DESCRIPTION 15 regulator that provides twice the current of the LM317 negative battery regulator. Charging is controlled by changing the set voltage of the regulators based on battery charge status. Flip-flop U703 determines whether the charge regulators will be set to 15.
CIRCUIT DESCRIPTION 16 BATTERIES AND P.E.M. The batteries used in the SR560 are of sealed lead-acid construction. There are three 12 V, 1.9 amp-hour batteries, two of which serve as the positive power supply, and one of which serves as the negative power supply.
CALIBRATION AND REPAIR 17 OFFSET ADJUSTMENT The SR560's front-panel offset adjustment provides an easy way for the user to null the amplifier's DC offset. Use the COUPLING pushbutton to light the GND LED. Now, regardless of the SOURCE setting, the input to the amplifier is grounded internally.
CALIBRATION AND REPAIR 18 SR560 OFFSET ADJUSTMENT PROCEDURE Required equipment: Digital volt meter Oscilloscope 4 BNC cables 1 BNC tee Function generator Small slotted screwdriver Phillips screwdriver Remove the bottom cover of SR560 to expose the component side of pc board.
CALIBRATION AND REPAIR 19 The other two fuses are in-line with the batte ries . The se fuse s w ill blow i f the rea r panel ± 12 VDC supplies are shorted, or if the unit sources or draws ex cessive current to o r fro m the ba tteri es.
CALIBRATION AND REPAIR 20 INPUT VOLTAGE NOISE The amplifier's input voltage noise approximates that of a 1000 Ω resistor (about 4 nV/ √ Hz). For source impedances below 1000 Ω , the output noise will be dominated by the amplifier's input voltage noise.
CALIBRATION AND REPAIR 21 Gain Input Noise (nV/ √ Hz ) Maximum DR (dB 0) 1 60 0 2 40 0 5 25 6 10, LN 13 6 10, HDR 25 14 20, LN 11 6 20, HDR 25 20 50, LN 10 14 50, HDR 25 28 100, LN 4 14 100, HDR 20 .
CALIBRATION AND REPAIR 22.
APPENDIX A A - 1 REMOTE PROGRAMMING Introduction The SR560 is equipped with a standard DB- 25 RS-232C connector on the rear panel for remote control of all instrument functions. The interface is configured as listen-only, 9600 baud DCE, 8-bit, no parity, 2 stop bits, and is optically isolated to prevent any noise or grounding problems.
APPENDIX A A - 2.
APPENDIX B B - 1 NOISE SOURCES AND CURES Noise, random and uncorrelated fluctuations of electronic signals, finds its way into experiments in a variety of ways. Good laboratory practice can reduce noise sources to a manageable level, and the lock-in technique can be used to recover signals, which may still be buried in noise.
APPENDIX B B-2 ways which these noise sources work their way into an experiment. Capacitive Coupling A voltage on a nearby piece of apparatus (or operator) can couple to a detector via a stray capacitance. Although C stray may be very small, the coupled in noise may still be larger than a weak experimental signal.
APPENDIX B B-3 Resistive Coupling (or ‘Ground Loops’) Currents through common connections can give rise to noise voltages. Resistive Coupling Here, the detector is measuring the voltage across the experiment, plus the voltage due to the noise current passing through the finite resistance of the ground bus.
APPENDIX B B-4.
SR560 COMPONENT PARTS LIST C-1 Front Panel Parts List REF. SRS part# VALUE DESCRIPTION D 1 3-00884-306 RED LED, Rectangular D 2 3-00012-306 GREEN LED, Rectangular D 3 3-00012-306 GREEN LED, Rectangula.
SR560 COMPONENT PARTS LIST C-2 D 48 3-00004-301 1N4148 Diode J 1 1-00035-130 20 PIN DIL Connector, Male N 1 4-00651-425 270X9 Resi stor Network SIP 1/4W 2% (Common) N 2 4-00651-425 270X9 Resi stor Net.
SR560 COMPONENT PARTS LIST C-3 C 112 5-00023-529 .1U Cap, Monolythic Ceramic, 50V, 20%, Z5U C 113 5-00100-517 2.2U Capacitor, Tantalum, 35V, 20%, Rad C 114 5-00100-517 2.
SR560 COMPONENT PARTS LIST C-4 C 319 5-00033-520 47U Capacitor, Electrolytic, 16V, 20%, Rad C 320 5-00033-520 47U Capacitor, Electrolytic, 16V, 20%, Rad C 321 5-00031-520 220U Capacito r, Electrolytic.
SR560 COMPONENT PARTS LIST C-5 C 804 5-00225-548 .1U AXIAL Capacitor, Cerami c, 50V,+80/-20% Z5U AX C 805 5-00225-548 .1U AXIAL Capacitor, Cerami c, 50V,+80/-20% Z5U AX C 806 5-00225-548 .1U AXIAL Capacitor, Cerami c, 50V,+80/-20% Z5U AX C 807 5-00225-548 .
SR560 COMPONENT PARTS LIST C-6 D 705 3-00011-303 RED LED, T1 Package D 706 3-00062-340 KBP201G/BR-81D Integrat ed Circuit (Thru-hole Pkg) D 707 3-00226-301 1N5822 Diode D 708 3-00226-301 1N5822 Diode D 709 3-00306-340 LM385BZ-2.
SR560 COMPONENT PARTS LIST C-7 Q 703 3-00374-329 MTP20P06 Voltage Reg., TO-220 (TAB) Package Q 801 3-00376-329 MTP5N05 Voltage Reg., TO-220 (TAB) Package R 2 4-00616-453 49.
SR560 COMPONENT PARTS LIST C-8 R 212 4-00600-40 7 15.8K Res istor, Meta l Film , 1/8W , 1%, 50PPM R 213 4-00600-40 7 15.8K Res istor, Meta l Film , 1/8W , 1%, 50PPM R 214 4-00030-40 1 10 Resistor , Ca.
SR560 COMPONENT PARTS LIST C-9 R 403 4-00325-40 7 845 Resist or, Meta l Film , 1/8W , 1%, 50PPM R 404 4-00165-40 7 200 Resist or, Meta l Film , 1/8W , 1%, 50PPM R 405 4-00030-40 1 10 Resistor , Carbon.
SR560 COMPONENT PARTS LIST C-10 R 707 4-00042-401 15K Resistor, Carbon Film, 1/4W, 5% R 708 4-00376-407 2.87K Resistor, Metal Film, 1/8W, 1%, 50PPM R 709 4-00169-407 249 Resistor, Metal Film, 1/8W, 1%.
SR560 COMPONENT PARTS LIST C-11 U 101 3-00371-340 DG444 Integrated Circuit (Thru-hole Pkg) U 102 3-00382-340 OPA37 Integrated Circuit (Thru-hole Pkg) U 103 3-00090-340 LF411 Integrated Circuit (Thru-h.
SR560 COMPONENT PARTS LIST C-12 U 801 3-00112-329 7805 Voltage Reg., TO-220 (TAB) Package U 802 3-00307-340 LM2940T-10 Integrated Circuit (Th ru-hole Pkg) U 803 3-00090-340 LF411 Integrated Circuit (T.
SR560 COMPONENT PARTS LIST C-13 Z 0 0-00666-050 23" #18 WHITE Wire #18 UL1007 Stripped 3/8x3/8 No Tin Z 0 0-00667-050 20" #18 WHITE Wire #18 UL1007 Stripped 3/8x3/8 No Tin Z 0 1-00124-178 4 PIN Connector Housing, Plug Z 0 1-00125-179 4 PIN Connector Housing, Rece ptacle Z 0 1-00126-176 .
SR560 COMPONENT PARTS LIST C-14.
An important point after buying a device SRS Labs SR560 (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought SRS Labs SR560 yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data SRS Labs SR560 - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, SRS Labs SR560 you will learn all the available features of the product, as well as information on its operation. The information that you get SRS Labs SR560 will certainly help you make a decision on the purchase.
If you already are a holder of SRS Labs SR560, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime SRS Labs SR560.
However, one of the most important roles played by the user manual is to help in solving problems with SRS Labs SR560. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device SRS Labs SR560 along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
