technical manual for the experimental acoustic flow monitor · low power consumption circuit. the...
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Technical Manual for the Experimental Acoustic Flow Monitor
By Kevin C. Hadley and Richard LaHusen
U.S. GEOLOGICAL SURVEY Open-File Report 95-114
Vancouver, Washington 1995
U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary
U.S. GEOLOGICAL SURVEY GORDON P. EATON, Director
Use of brand names in this report is for identification purposes only and does not consititute endorsement by the U.S. Geological Survey.
For additional information Copies of this report can be write to: purchased from:
John E. Costa U.S. Geological Survey U.S. Geological Survey Earth Science Information Center 5400 MacArthur Blvd. Open-File Reports Section Vancouver, WA 98661 Box 25286, MS 517
Denver Federal Center Denver, CO 80225
CONTENTS
Abstract................................................................................................. 1
Introduction................................................................................................ 1
Purpose and Scope.................................................................................... 1
Acknowledgments................................................................................... 1
Theory of Operation....................................................................................... 2
System Overview......................................................................................... 2
Circuit Descriptions....................................................................................... 3
Sensor and Preamplifier................................................................................ 3
Signal Conditioning Circuit.............................................................................. 4
Analog/Digital Circuit.................................................................................. 4
Microprocessor Circuit................................................................................. 4
Symptom Analysis and Troubleshooting........................................................................10
Regulated Supply (+5VDC)........................................................................... 10
Operation of Circuit................................................................................... 11
References Cited............................................................................................. 11
Appendix 1- Printed Circuit Board (PCB) Component Layouts................................................. 12
Appendix 2-Printed Circuit Board (PCB) Parts List.......................................................... 16
Appendix 3-Acoustic Flow Monitor Module Hardware Connectivity Diagram.................................... 22
Appendix 4-Schematic Diagrams............................................................................ 24
FIGURES
1. Acoustic Flow Monitor system simplified functional block diagram ..................................... 2
2. Signal preamplifier schematic diagram ............................................................ 3
3. Signal conditioning circuit schematic diagram ...................................................... 5
4. Frequency response of the signal conditioning circuit................................................. 6
5. Analog multiplexer subcircuit schematic diagram.................................................... 6
6. Analog to Digital Converter subcircuit schematic diagram ............................................. 7
7. Microprocessor unit subcircuit schematic diagram ................................................... 8
8. Real time clock/calendar subcircuit schematic diagram ............................................... 9
9. Modem subcircuit schematic diagram ............................................................. 9
10. +5VDC regulated supply subcircuit schematic diagram .............................................. 10
Technical Manual for the Experimental Acoustic Flow MonitorBy Kevin C. Hadley and Richard G. LaHusen
Abstract
A debris flow detection system that monitors ground vibrations has been developed by the U.S. Geological Survey (USGS) in Vancouver, WA. The acoustic flow monitor (AFM) uses a non- contact method of flow detection for high reli ability. Prototype AFM systems were installed at several locations for evaluation, including Redoubt Volcano, Alaska; Mount Saint Helens, Washington; and Pinatubo Volcano, Philippines. The AFM hardware consists of a microprocessor based field module and a geophone sensor. The field module analyzes signals from the sensor and radio transmits data to a base station com puter. Electronic circuitry of the AFM consists of the sensor pre-amplifier, signal conditioning, analog to digital conversion, and microprocess ing sub-circuits. Circuit descriptions, schematic diagrams, and parts lists are provided in this tech nical manual to assist scientists and technicians using the prototype AFM to maintain their sys tems. A troubleshooting guide is provided for the electronic technician.
INTRODUCTION
A debris flow detection system that monitors in- ground acoustic vibrations has been developed by the U.S. Geological Survey (USGS) in Vancouver, Wash ington. The Acoustic Flow Monitor (AFM) experi mental model was first built in 1989 and tested during the 1990 eruptions of Redoubt Volcano, Alaska (Brantley, 1990). Since 1990, the AFM system has
been installed for evaluation purposes at Mount St. Helens and Mount Rainier in Washington, Jiangjia Ravine in China, Cotopaxi Volcano in Ecuador and Pinatubo Volcano in the Philippines (Hadley and LaHusen, 1991).
The AFM has several features that give it versatil ity and durability. The non-contact method of flow detection eliminates the need for repetitive and haz ardous maintenance of equipment after each debris flow, unlike a trip wire detection system. The AFM equipment is weatherproof, rugged, and has been proved to operate at remote sites under extreme tem perature and humidity conditions. Two-way radio communications enable automatic, real-time data transmissions from remote instrument sites to a base station receiver. Users have the ability to query the AFM field units from a base station computer to obtain data or modify system operating parameters.
Purpose and Scope
In support of cooperating scientists and techni cians who are currently utilizing the AFM experimen tal model, this manual is intended to provide the necessary technical information for persons with a working knowledge of electronics to maintain the AFM hardware. Schematic diagrams, component lay outs and parts lists are provided, as well as guidelines for troubleshooting the circuitry.
Acknowledgments
The authors would like to acknowledge those per sons who have provided assistance to install, maintain and provide evaluation comments on the hardware,
SIGNAL CONDITIONING CIRCUIT
MICROPROCESSING CIRCUITANALOG/DIGITAL CIRCUIT
Rgure 1. Acoustic Flow Monitor system simplified functional block diagram.
software and performance of the experimental AFM systems. In particular, individuals who have provided exceptional support include: Joe Dorava of the Alaska Volcano Observatory, Jinfan Duan and Ye Mingfu at the Dongchuan Debris Flow Observation Center in China, Patricia Mothes and Wilson Enriques of the Institute Geofisico-Escuela Politecnica Nacional in Quito, Ecuador and Sergio Marcial and Arnoldo Melosantos of the Philippine Institute of Volcanology and Seismology.
THEORY OF OPERATION
The AFM is a micro-powered field computer pro grammed to continuously analyze the amplitude, fre quency and duration of ground vibrations. The AFM reads and transmits digital data via UHF radio back to a base station receiver at timed intervals. If debris flow activity is detected a data set is sent immediately.
The AFM is designed to analyze the frequency spectrum, 10 to 100 Hz, where acoustic ground sig nals generated by debris flows are known to occur (Okuda and others, 1979). A geophone sensor con verts ground motion to input signals for the AFM module. Input peak amplitude values are compared with a 'threshold' value stored in the AFM memory.
If input signal levels exceed the threshold the AFM begins tracking the elapsed time that input levels remain above threshold and compares the elapsed time with a 'duration' value stored in memory. If the elapsed time value exceeds the duration the AFM jumps to an alert mode resulting in an immediate data set transmission that is flagged to indicate a debris flow alert status. The AFM will remain in alert mode and continue to send flagged data at 1 minute intervals while input levels remain above threshold. When the signal level drops below threshold the AFM resumes normal operation sending unflagged data transmis sions at preset timed intervals, typically every 30 min utes. The threshold, duration and frequency band values define the criteria for debris flow detection by the AFM. These parameters may vary depending on desired sensitivity of the unit at each field site.
SYSTEM OVERVIEW
The AFM circuitry is composed of several func tional subsystems (fig. 1). The geophone sensor con verts vertical ground velocity to an analog signal. A signal preamplifier located near the geophone sensor maximizes the input signal-to-noise ratio to the AFM
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from the sensor cable. The amplified signal is filtered into 3 frequency components by the signal condition ing circuit of the AFM module. An analog multiplexer (MUX) consecutively selects the 3 input channels to be digitized by the analog-to-digital converter (ADC). The micro-processing unit (MPU) controls input channel selection and analog-to-digital conver sions. The MPU also controls radio communications. Radio transmissions are activated by the push-to-talk (FIT) circuit and data are modulated by the 300 baud modem and passed to the radio transmitter. The AFM, while analyzing acoustic data, monitors radio commu nications for commands from the base station or other AFM units.
CIRCUIT DESCRIPTIONS
Appendixes in this report include complete sche matic diagrams, component layout diagrams, hard ware connectivity diagram, and parts lists for circuits discussed. Sub-circuit diagrams are included in this section for quick reference.
Sensor and Preamplifier
The AFM system uses a Mark Products model L10-AR geophone as the vibration sensor. The geo- phone is inexpensive, waterproof and ragged. It has a specified -3db frequency response of 10-250 hertz with no spurious responses. The sensor is operated critically damped (0.7 damping) to provide a flat fre quency response and prevent overshoot at the 10 hertz resonant frequency.
The signal preamplifier (fig. 2) is a low offset, low power consumption circuit. The printed circuit board (PCB) is cast in epoxy resin for protection against moisture and physical damage. Therefore, the circuit is unserviceable and must be replaced if faulty.
Power to the preamplifier board is provided by the primary +12VDC battery supply and regulated to +5VDC by U3. Cl and C2 decouple transient signals from the DC supplies.
Ul provides -5VDC to U2 by inverting the output from U3. C3 and C4 function as a charge pump/res ervoir for Ul. C5 is a decoupling capacitor for the output of Ul.
Signal gain of U2 is controlled by the value of Rl with the relation {GainU2 = 10 + (360K/R1)}. Rl is fixed at 2K giving a gain of 190. The output from U2 is applied to the signal conditioning circuit via the geophone cable.
Signal Conditioning Circuit
The signal conditioning circuit (Fig. 3) consists of an amplifier and an array of low pass and high pass filters with associated peak detectors. The signal from the geophone cable is passed through a 300 Hz low pass filter and then amplified (XI1). Three paral lel filters split the signal into 3 frequency bands: 1) 10-300 Hz, 2) 10-100 Hz and 3) 100-300 Hz. Fre quency responses are shown in figure 4. The 10 Hz lower limit is a-function of the geophone frequency response. Peak detectors on the output of each filter track peak signal amplitudes for analysis.
Power to the signal conditioning PCB is derived from the +5VDC power bus on the A/D PCB, dis cussed in a later section. Ul provides a -5VDC to U2 and U3 by inverting the +5VDC. C4 and C5 are charge pump and reservoir capacitors respectively for Ul. AC decoupling capacitors (.1 uF) are used throughout the circuit to eliminate transients on the power supply bus. The 300 Hz low pass filter on the input consists of one-fourth U2, Rl and C6. C8 and C9 are AC coupling capacitors with biasing resistors R2 and R5 respectively. The filtered signal is ampli fied by one-fourth U2, R3 and R4. The signal is fil tered by 3 parallel filter circuits consisting of one- fourth U2, R6 and C12 (300 Hz low pass); one-fourth U3, R8, C13 and one-fourth U3, R9, C14 (2-stage 100 Hz low pass); and one-fourth U3, C16, Rl 1 and one-fourth U3, R12, C20 (2-stage 100 Hz high pass). Diodes Dl, D2 and D3 and their correspond ing operational amplifiers U2 and U3 function as amplitude rectifiers. Capacitors Cll, CIS and C19 with resistors R7, RIO, and R13 respectively provide an envelope output of peak amplitude levels for each frequency band on Jl. The outputs are applied to the mux input channels on the Analog/Digital circuit.
Analog/Digital Circuit
The Analog/Digital (A/D) PCB contains 5 sub- circuits: 1) the analog multiplexer (MUX), 2) -5VDC power supply, 3) peripheral interface adapter (PIA), 4) 12 bit analog-to-digital converter (ADC), and 5) address decoder circuits.
Signal inputs are coupled to the A/D PCB through connector P2 and appear on MUX U3 pins 13,14, and 15 (fig. 5). Channel selection is con trolled by logic levels applied to U3, pins 9,10, and 11 from PIA Ul pins 4,3, and 2 respectively (see Appendix 4). The MUX output on U3, pin 3 is buff ered by U9 and applied to ADC U2, pin 3 (fig. 6).
An analog to digital conversion is initiated by a write cycle to U2 that toggles U2, pin 9 and 10 to a low logic level. A 2 millisecond software pause allows completion of the conversion before the first byte is read. A read cycle occurs when U2, pin 11 is toggled low via inverter U5. The high byte (bits 0 through 7) is read on the first read cycle and the low byte (bits 8 through 12) on the second. The conver sion and read steps are repeated for each input signal channel.
Power to the A/D PCB on P3, pin 36 is derived from the +5VDC regulated supply of the MPU PCB, discussed later in this section. U10 inverts the +5VDC supply producing a -5VDC supply output to U2, U3 and U4. U8 provides a stable +5VDC refer ence to U2. LI and Dl operate as a one way charge pump and C18 as a reservoir for U10.
Chip selection for the A/D PCB is controlled by - U6 which decodes addresses appearing at U6, pins 1, 2 and 3.
Microprocessor Unit Circuit
Subcircuits on the MPU PCB include: 1) the microprocessor unit (MPU) and memory, 2) address decoder, 3) real-time clock, 4) 300 baud modem, and 5) regulated power supply circuits.
MPU Ul is an 8-bit CMOS microprocessor. The instruction code for Ul is stored in U3, UV-eras- able read-only memory (EPROM) (see Appendix 4). Random access memory (RAM) for MPU Ul is pro vided by U4. Upon power-up, the inputs on Ul, pins 8,9, and 10 are latched to set the MPU mode of oper ation (fig. 7). The mode of operation is set for a mul tiplexed AO-A7 address/DO-D7 data bus and an externally derived serial communications clock. Address lines AO-A7 are latched to the address bus by U2 and controlled by the address strobe at Ul, pin 39 (see Appendix 4). The serial communications inter face (SCI) of Ul is set at 300 baud by the pulse rate from U7, pin 13 which is gated through U8 and applied to Ul, pin 10. The system clock frequency (E) appearing at Ul, pin 40 is equal to 614 KHz or
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one-fourth the oscillating frequency of Yl. In addition to setting modes of operation, Ul also establishes the AFM station identification (ID) number by reading the inputs on Ul, pins 16,17, and 18 which are manually set with switch SW2.
A restart of the AFM will occur with a restoration of power to the unit or by resetting the MPU with SW1. Upon restart operating parameters including: 1) threshold, 2) duration and 3) transmit interval are set to default values in the instruction code stored in U3.
U10 is a real time clock/calendar that interfaces directly with Ul and has programmable operation modes (fig. 8). Upon restart, Ul writes to the U10 command register setting the clock operation modes to a 24 hour cycle with an oscillator frequency of 32.768 KHz provided by Y3, C20, and C21. If primary power to U10 is removed backup power from battery BT1 will maintain clock operation and settings.
Modem U5 interfaces the MPU SCI I/O ports (Ul, pin 11 & 12) to the UHF transceiver (fig. 9). U5 has originate and answer modes of operation that are con trolled by the logic level appearing on U5, pin 13. A logic high from Ul, pin 19 simultaneously sets U5 to originate mode and activates the push-to-talk (PTT) circuit (Ql) enabling the radio transmitter. Data trans mitted from Ul, pin 12 appears on U5, pin 11. The
modulated data output on U5, pin 17 is sent to the transmitter. On the receive side, data from the receiver appears on U5, pin 16. The demodulated digital data on U5, pin 5 is applied to Ul, pin 11. Transmit and receive digital data appear at TP3 and TP2 respectively for test purposes. Tl and T2 pro vide impedance matching between the modem and transceiver. The transmit level of U5 (-9 dbm) is set by R7. Carrier detect timing and carrier detect threshold circuits internal to U5 are set by C14 and CIS on U5, pins 4 and 7 respectively.
Address decoder Ul 1 decodes Ul address bus lines A13, A14, and A15 on Ul 1, pins 1,2, and 3 respectively for chip selection on the MPU PCB (see Appendix 4).
Power to the MPU, A/D, and signal conditioning PCB's is provided by a +5VDC regulating supply cir cuit including U6 and Q3 (fig. 10). Dl and Rl 1 form a voltage reference to amplifier U6. U6 drives transis tor Q3 and feedback from the emitter of Q3 is applied to U6, pin 2. U6 adjusts the base current of Q3 to maintain a regulated +5VDC supply. RIO sets the quiescent operating current of U6.
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SYMPTOM ANALYSIS AND TROUBLESHOOTING
Troubleshooting and repairing of the AFM elec tronics requires a trained technician who has a solid understanding of electronic principles, both analog and digital, and proper test/repair procedures. The fol lowing guide will assist the technician in isolating a problem area on the circuit board. Knowledge of the test equipment and theory of operation of the circuits is imperative to effectively troubleshoot problems to the component level.
Equipment needed: 1) multimeter, 2) oscilloscope, 3) signal generator, 4) watt meter, 5) frequency counter and 6) radio scanner.
Regulated supply (+5VDC)
Symptom: +5VDC supply absent from all or part ofcircuit.Areas to check:
1) +12VDC primary power input to the PCB - using a multimeter measure the voltage across J4 on the MPU PCB (see Appendix 1). (12 -14.5 volts = ok).
2) The +5VDC regulated supply circuit - measure the voltage at TP4 (4.8 - 5.2 volts = ok).
3) The +5VDC supply bus - verify continuity of the +5VDC supply bus to problem areas.
Symptom: Excessive current consumption. Normal maximum current consumption (not includ ing radio):
Total, all PCBs (< 35mA = ok).MPU and A/D only (< 30mA = ok)MPU only (<20mA = ok)
Areas to check:1) PCB solder side - inspect the solder side of the
PCB for solder bridges or shorted leads (applies pri marily to newly constructed or reworked boards). If corrosion is present on older boards, remove it and recheck current consumption.
2) Component side; integrated circuit (1C) or dis crete component - Visually look for signs of a faulty component such as discolored, chipped, or broken component cases. Check for bent component leads or 1C pins and pins not fully inserted into a socket.
3) 1C removal - If component failure is suspected power down the circuit and remove all IC's. Never insert or remove IC's from a powered circuit. Dis charge C16 before removing or inserting IC's. With all IC's removed, power up the circuit and recheck supply current consumption (< 10mA = ok). If cur rent consumption is still high then a defective discrete component exists. Capacitors generally have a higher
10
failure rate than resistors. If an 1C is suspected insert IC's one at a time, with the MPU inserted last, and recheck current consumption, looking for a consider able increase. Replace IC's drawing high current. Electrical characteristics for IC's can be found in man ufacturers data books.
Operation of circuit
Symptom: No data is transmitted from AFM Areas to check:
1) Radio transceiver - with a watt meter and fre quency counter, verify that the radio transmitter is functioning properly by measuring the output power and carrier frequency, (refer to the manufacturers radio specifications for tolerances).
2) Modem/PTT interface - with the radio con nected to the AFM and power on, perform the follow ing tests:
a) Use a scanner tuned to the transmit frequency to listen for a modem tone (2225Hz) while keying the transmitter. No tone indicates a problem in the modem interface circuit.
b) Initiate an AFM restart with reset switch SW1 of the MPU PCB located on the outside of the PCB enclosure and listen for data being transmitted imme diately after restart. Frequency shift keying (FSK) from modem U5 should be clearly heard. No FSK indicates no data being modulated by U5.
c) Verify the PTT circuit is operating. If, upon restart of the AFM, there is no radio carrier present then a problem in the PTT circuit exists. Ground J3, pin 1 on the MPU board. This should activate the transmitter; otherwise, a problem in the cabling to the radio is likely.
3) MPU PCB - with an oscilloscope check the sys tem clock signal (E) from Ul at TP1 (614KHz, 5V pk- pk, square wave = ok). Monitor TP3 on the oscillo scope while initiating a MPU reset with SW1. Look for digital data being transmitted immediately after reset (+5VDC, square wave = ok).
Symptom: Digital data values not consistent with analog input. Areas to check:
1) Geophone/pre-amp sensor - view the amplified output of the sensor at TP1 on the signal conditioning PCB with an oscilloscope while gently vibrating the geophone (max. 2-3 volts pk-pk, sine wave = ok).
2) Signal conditioning PCB - using a signal gen erator inject a sine wave (max. 4-5 volts pk-pk) to the input of the signal conditioning circuit on TP1. J2-3 is signal ground. Perform the following tests: (Refer to fig. 3)
a) Sweep the generator frequency from 10 to 300Hz while observing the lOOHz high pass output on TP8. The output should increase to a maximum at 300Hz.
b) Sweep back from 300 to lOHz while observing the lOOHz low pass output on TP6. The output should increase to a maximum at lOHz.
c) The 300Hz low pass dc output level on TP4 should have a flat response over the full 10 to 300Hz range.
3) A/D PCB - check the voltage reference to ADC U2 on pin 5 (+5.00 +/- .05VDC = ok). If an AFM base station system is available to receive and view data perform the following tests:
a) Apply +5VDC to MUX input channel INO, INI, and IN2 on P2, pins 26,25, and 24 respectively.
b) Measure the voltage on the analog input to ADC U2, pin 3 (+5VDC = ok).
c) Restart the MPU and check data values received at the base station (approx. 4095 all chan nels = ok).
Erroneous data indicate problems with the MUX input channel selection circuitry, which includes PIA Ul, or with ADC U2. Note, a constant digital value of 1285 on all channels indicates the MPU does not acknowledge ADC U2 on the data bus. Check conti nuity between the MPU and A/D PCBs.
REFERENCES
Brantley, S., ed. 1990, The eruption of Redoubt Volcano, Alaska, December 14,1989 -August31,1990, U.S. Geological Survey Circular 1061, p. 27-31.
Hadley K.C. and LaHusen R.G., 1991, Deployment of an acousticflow monitor system and examples of its application at Mount Pinatubo, Philippines: EOS, Transactions, American Geophysical Union, v. 72, no. 44, p. 67.
Okuda, S., Suwa, H., Okunishi, K., Yokoyama, K., Ogawa, K., and Hamana, S., 1979, Synthetic observation on debris flow, Annals of Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan, Volume 22 B-l, pp 157-204 (in Japanese).
11
APPENDIX 1Printed Circuit Board (PCB) component layouts
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39.
1 /ml
Microprocessor unit (MPU) PCB component layout.
15
APPENDIX 2Printed Circuit Board (PCB) parts list
16
APPENDIX 2
Ref.No.ClC2C3C4C5RlUlU2U3
Pre-amplifier PCB:
DescriptionCapacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., lOuF, 16V, +/- 20%Capacitor, elect., lOuF, 16V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Resistor, met. film, 2.0K Ohm, 1/4W, +/- 1%1C, C-MOS, voltage inverter, ICL76621C, amplifier, instrumentation, HD84021C, +5V regulator, 3-terminal, 78L05
MFR'sMultipleMultipleMultipleMultipleMultipleMultipleMultipleHydelcoMultiple
17
APPENDIX 2
Ref.No.ClC2C3C4C5C6C7C8C9CIOCllC12C13C14C15C16C17CISC19C20C21DlD2D3RlR2R3R4R5R6R7R8R9RIORllR12R13R14R15R16UlU2U3
Signal conditioning PCB:
DescriptionCapacitor, elect., lOOuF, 16V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, poly, film, .luF, 63V, +/- 10%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., NP, 4.7uF, 50V, +/- 10%Capacitor, elect., NP, 4.7uF, 50V, +/- 10%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., NP, 4.7uF, 50V, +/- 10%Capacitor, poly, film, .luF, 63V, +/- 10%Capacitor, poly, film, .luF, 63V, +/- 10%Capacitor, poly, film, .luF, 63V, +/- 10%Capacitor, elect., NP, 4.7uF, 50V, +/- 10%Capacitor, poly, film, .luF, 63V, +/- 10%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., NP, 4.7uF, 50V, +/- 10%Capacitor, poly, film, .luF, 63V, +/- 10%Capacitor, elect., lOOOuF, 16V, +/- 20%Diode, silicon, signal, 1N4148, or 1N914Diode, silicon, signal, 1N4148, or 1N914Diode, silicon, signal, 1N4148, or 1N914Resistor, carbon, 3K Ohm, 1/4W, +/- 5%Resistor, carbon, 20K Ohm, 1/4W, +/- 5%Resistor, met. film, l.OK Ohm, 1/4W, +/- 1%Resistor, met. film, 10.0K Ohm, 1/4W, +/- 1%Resistor, carbon, 20K Ohm, 1/4W, +/- 5%Resistor, carbon, 3K Ohm, 1/4W, +/- 5%Resistor, carbon, 200K Ohm, 1/4W, +/- 5%Resistor, met film, 16.2KOhm, 1/4W, +/- 1%Resistor, met. film, 16.2K Ohm, 1/4W, +/- 1%Resistor, carbon, 200K Ohm, 1/4W, +/- 5%Resistor, met. film, 16.2K Ohm, 1/4W, +/- 1%Resistor, met. film, 16.2K Ohm, 1/4W, +/- 1%Resistor, carbon, 200K Ohm, 1/4W, +/- 5%Jumper, 0 OhmJumper, 0 OhmJumper, 0 Ohm1C, C-MOS, voltage inverter, ICL76621C, quad op. amp., low power, LT10141C, quad op. amp., low power, LT1014
MFR's
MultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultiple
MultipleLinear Techn.Linear Techn.
18
APPENDIX 2
Analog/Digital (A/D) PCB:
Ref.No.ClC2C3C4C5C6C7C8C9CIOCllC12C13C14C15C16C17CISC19C20C21C22C23DlLIPI
P2UlU2U3U4U5U6U7
U8U9U10
DescriptionCapacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., lOuF, 16V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., lOuF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Diode, silicon, signal, 1N4148 or 1N914Choke, 330uH, 100mA, Q min = 60, 43LS334Switch/connector, 16-pin dip, 8-pin sip (May be omitted depending on application)Header, shrouded, 26-pin, for IDC connector1C, CMOS, peripheral interface adaptor (PIA)1C, CMOS, ADC, 12-bit + sign, ADC1205CCJ-11C, analog multiplexer, 8-channel, 4051C, analog multiplexer, 8-channel, 405 11C, C-MOS, Schmitt trg., hex inv., 74HC141C, C-MOS, 3-to-8 line decoder, 74HC1381C, C-MOS, magnitude comparator, 74HC688
1C, precision reference, 5V, LT10211C, C-MOS, op-amp, low power, ICL761 11C, C-MOS, regulator, inverting, MAX635
MFR'S
MultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMouser Elect.Multiple
3M,AMPHitachiNational Semi.MultipleMultipleMultipleMultipleNational Semi. HarrisLinear Techn.IntersilMaxim
19
APPENDIX 2
Microprocessor unit (MPU) PCB:Ref.No.BTlClC2C3C4C5C6C7C8C9CIOCllC12CISC14CISC16C17CISC19C20C21C22C23C24DlQiQ2RlR2R3R4R5R6R7R8R9RIORllR12R13R14
DescriptionBattery, lithium coin, 3VCapacitor, elect., lOOuF, 16V, +/- 20%Capacitor, ceramic, 15pF, 50V, +/- 20%Capacitor, ceramic, 15pF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., lOuF, 16V, +/- 20%Capacitor, elect., lOOuF, 16V, +/- 20%Capacitor, elect., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, ceramic, 15pF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, elect., lOOOOuF, 16V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, ceramic, 15pF, 50V, +' WoCapacitor, ceramic, 15pF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Capacitor, monolith., .luF, 50V, +/- 20%Diode, reference, LM 336-5.0, 5.0VTransistor, power, mosfet, IFR511, 60V, 4ATransistor, power, NPN, TIP29Resistor, carbon, 10K Ohm, 1/4W, +/- 5%Resistor, carbon, 10K Ohm, 1/4W, +/- 5%Resistor, carbon, 10K Ohm, 1/4W, +/- 5%Resistor, carbon, 620 Ohm, 1/4W, +/- 5%Resistor, carbon, 620 Ohm, 1/4W, +/- 5%Resistor, carbon, 2K Ohm, 1/4W, +/- 5%Resistor, carbon, 5K Ohm, 1/4W, +/- 5%Resistor, carbon, 2K Ohm, 1/4W, +/- 5%Resistor, carbon, IK Ohm, 1/4W, +/- 5%Resistor, carbon, 1M Ohm, 1/4W, +/- 5%Resistor, carbon, 10K Ohm, 1/4W, +/- 5%Resistor, carbon, 510K Ohm, 1/4W, +/- 5%Jumper, 0 OhmResistor, carbon, 10K Ohm, 1/4W, +/- 5%
MFR'S
MultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleNational Semi.MultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultipleMultiple
20
APPENDIX 2
Ref.No.R15
R16R17R18SW1SW2TlT2UlU2U3U4U5U6U7U8U9U10UllYlY2Y3
Microprocessor unit (MPU) PCB cont...
DescriptionResistor, carbon, 10K Ohm, 1/4W, +/- 5%Resistor, carbon, 20K Ohm, 1/4W, +/- 5%
Resistor, carbon, 20K Ohm, 1/4W, +/- 5%
Resistor, carbon, 20K Ohm, 1/4W, +/- 5%
Switch, push button, momentary, N.O.
Switch, thumbwheel, binary coded, EECO 1400
Transformer, audio, 4K - 600 ohm, TL021
Transformer, audio, 4K - 600 ohm, TL02 1
1C, C-MOS, MPU, HD6303RP
1C, C-MOS, Octal D-type latch, 74HC373
1C, C-MOS, Eprom, 64K, UV erase, 27C64
1C, C-MOS, Static RAM, 64K, 6264
1C, C-MOS, Modem, 300 baud, 74HC943
1C, Op-amp, programmable, LM4250
1C, Binary counter, 12-stage 4040
1C, C-MOS, AND gate, triple 3-input, 74HC1 1
1C, C-MOS, Schmitt trg., hex inv., 74HC14
1C, C-MOS, Real time clock, ICM7170
1C, C-MOS, 3 to 8 line decoder, 74HC138
Crystal, quartz, 2.4576Mhz
Crystal, quartz, 3.579545Mhz
Crystal, quartz, 32.768Khz
MFR's
MultipleMultiple
Multiple
Multiple
Multiple
Multiple
Mouser Elect.
Mouser Elect.
Hitachi
Multiple
Multiple
Multiple
National Semi.
National Semi.
Multiple
Multiple
Multiple
Intersil/Harris
Multiple
Multiple
National Semi.
Multiple
21
APPENDIX 3Acoustic Flow Monitor module hardware connectivity diagram
22
APPENDIX 3
Connectors:12VDC Sensor Input InputflAl ABCDE
RF Output
-BlkRed
Pin A--hi 2 VDC (Red) B = Sensor Big. gnd. (Blk) C = Sensor Big. (Grn) D-N/C
2-Wire cable-
TB1 2 - Wire cables: + Red/-Blk
SignalConditioning
PCB
MPU and A/D PCB ? S
26 COND. RIBBON:1 « SVDCpiil2 = GND(Bllc)
24 = CH
'4-Wire cable: TX signal (Red) RX signal (Grn) PTT (White) Gnd (Blk)
RADIO
Acoustic Flow Monitor hardware connectivity diagram.
23
APPENDIX 4Schematic diagrams
24
AP
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ND
IX
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dia
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U.8. Geological Survey
APR 1 12000
Denver Library
APPENDIX 4
71 71 71 71 71 71 r Z 710.0.0.0.0.0.0.0.
IRQA PB7R/P PB6E_ PB5cs2 PBHCSO PB3UCC PB2CS1 PB1GMD - PBO Al r> PAO
Ucc P=Q GND A5
DB7,12 INT 6,18 +Uin 5,13 -Uin
03 x QH^AIOQ5 All
RO1,9 a STS
DBO,8 V- CS AVcc CLKIN AGMD WR DGND RD DVcc
12U
5V -*-
5i
20 Jurq
Vi
V
5 678
U9<OFFST> n ^ -
L< V+IQ
X^j L
U-
j _ 2 _ 3 _ 4
7611
-5V
^i-C191 "f.luF
« 7
~6
MC Vi, , MCcxJ NC NC 2TRM Vo GND
c. 1 3
4
C13
.luF ^
Ui 1. 2
34
U10 1N
-Uo LX LBO +VS LBI Uref HND urn
\A 4148
56 .
L ,l330uH
_k. t=i i
Z-.J-C48J Ti°uF
635
lllilllllllJCXJ
CXJr- CXJ UT
CXJ
P3 - CAHD EDGE CONNECTION TO MICHOPHOCESSOH UNIT CIRCUITNotes:1. Jl to -5V for bi-polar; Jl to Gnd for uni-polar2. U4 optional for additional analog inputs3. U5 is 74HC14
Analog/Digital (A/D) Circuit schematic diagram