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T H I S W A R R A N T Y I S I N L I E U O F A L L O T H E R WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY OF FITNESS FOR A PARTICULAR PURPOSE. Grason-Stadler A Welch Allyn Company Grason-Stadler, Inc. 1 Westchester Drive Milford, NH 03055-3056 Telephone: 603-672-0470 Fax: 603-672-0487 Service Manual 1717-0110, , Rev.
Table of Contents Warranty Table of Warning Key to Symbols Used on Schematics viii Foreword ......SECTION 1 - PRODUCT SPECIFICATIONS Catalog Listings Standards...
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F O R E W O R D GENERAL SERVICE INFORMATION Operating, check-out procedures, trouble-shooting hints, etc., can be found in the Instruction Manual (1717-0100). Repair and/or bench testing of GSI 17 Audiometers should only be performed by trained personnel. The following instructions are provided primarily for use by persons who are skilled in the repair of electronic equipment.
S E C T I O N 1 Product Specifications 1.1 CATALOG LISTINGS 1717-9700 GSI 17 Audiometer, AC Power (USA) 1717-9710 GSI 17 Audiometer, AC Power and Battery (USA) 1717-9705 GSI 17 Audiometer, AC Power (Export) 1717-9715 GSI 17 Audiometer, AC Power and Battery (Export) 1.2 STANDARDS This unit is a single channel, pure tone screening audiometer.
1.4 OUTPUT HEARING LEVEL CONTROL CALIBRATED IN dB HL MEASURED IN INCREMENTS OF 5 dB RANGES -10 to dB B HL -10 to 90 dB B HL 500 to 6000 250 and 8000 Hz -10 to 70 dB B HL "+10 dB"...
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1.7 STIMULUS TYPES Continuous Tone Continuous FM Tone Pulsed Tone SIGNAL FORMAT Continuous - Signal steady as long as Present Bar is depressed. Pulsed - Pulsed Rate: 2.5 Pulses/sec Pulse rate is synchronized to the "Present Bar" so that first and last pulse will have 200 ms on time. DUTY CYCLE RISE/FALL TIME 20-50 ms...
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INDICATORS: Power ON/OFF Frequency Selector dB HL - LCD Left/Right Earphone Pulsed/Steady/FM Subject Response - LED "Battery Low" (when applicable, i.e. Battery Option purchased) - LCD Tone ON - LED Extended Range - LCD REAR PANEL CONNECTORS Left and Right Earphone - 1/4" Phone Jack Subject Response Switch - 1/4"...
1.10 POWER AND POWER LINE POWER RATING 9 Watts power module operated while simultaneously charging battery. 0.6 Watts battery power OPERATING MODES Power Line (Mains) Battery - Rechargeable (NiCad) or Non-Rechargeable (Alkaline) LINE (MAINS) VOLTAGE 115 V or 220 V LINE (MAINS) VOLTAGE VARIATION LINE (MAINS) FREQUENCY RANGE 50-60 Hz...
MECHANICAL DIMENSIONS 1.13 Weight: 5.6 lbs (2.53 Kg) Weight of Battery Pack: 1.5 lbs (0.68 Kg) Size: 13.25"W x 14"D x 3.75"H (33.66 cm x 35.56 cm x 9.53 cm) 1.14 MATERIALS USED IN MANUFACTURE GSI 17 Case Assembly - GE Cycolac T Battery Option Case Assembly - GE Cycolac T Power Module Case Assembly - Noryl SE - 100J (Flame Retardant)
1.18 ACCESSORIES Supplied Cataloq Numbers Test Headset (TDH39) 8000-0175 Audiogram Forms (1 pad of 50) 1717-9600 Instruction Manual 1717-0100 Battery Pack Assembly 1717-2010 (used with 1717-9710, 1717-9715 models only) AC Power Cord, one of the following: 120 v (US) 8000-0240 220 V (Euro plug) 8000-0241 240 V (UK)
S E C T I O N 2 Functional Description This section of the Service Manual is used to describe Connectors, Controls, and Indicators of the GSI 17. Refer to Figure 2-l for the layout and positioning of Connectors, Controls, and Indicators. THE FRONT PANEL CONTROLS AND INDICATORS (FIGURE 2-1) F1 - Power switch and indicators for ON and OFF (0).
2.2 REAR PANEL CONNECTORS AND INDICATORS R1 - Power input jack with front panel indication of position and rear panel indication of input power specifications. R2 - Attention, consult accompanying documents. R3 - Earphone output jacks with front panel indication of left and right phone provided by illustration of subject.
The RAM will be tested using a read after write verification process. After each location is tested its value will be initialized to 0. If an error is detected, an error code will be displayed on the HL display and the instrument will halt.
S E C T I O N Routine Maintenance 3.1 EARPHONE CORDS With extended use, earphone cords tend to fray internally at junctions with both earphone and audiometer connectors. This fraying will ultimately either decrease the signal level in associated earphone or cause signals to be intermittent as cord is flexed.
3.4 SPECIAL MESSAGES microprocessor-controlled instrument GSI 17 is a which performs a self check each time the instrument is turned on (the self check does not occur when the instrument is "awakened" from Certain messages will be displayed to the sleep mode).
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4.1 QUICK REFERENCE CALIBRATION Select Calibration Mode using Cal/Norm Switch. Select Frequency and Reference HL for calibration. Select Earphone Routing (L or R). Turn Tone ON using Present Bar. NOTE: Display will update to the ANSI SPL required for proper calibration - subtract or add microphone corrections as necessary.
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Table 4-l: CALIBRATION REFERENCE THRESHOLDS Freq (Hz) 1500 2000 3000 4000 6000 8000 1000 45.0 25.5 11.5 10.0 15.5 13.0 Standard Reference Threshold Levels re: 20 uPa for Telephonics TDH39-P earphones as measured on the National Bureau of Standards 9-A coupler. Reference ANSI S3.6-1989, IS0 389-1975 Standards.
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Switch # Function OFF (down) ON (up) Default Data Load Loads the default Calibration data into EEPROM when the Calibration Mode is entered. Custom SPL Mode Custom Enables the selection of user specified SPL values during the transducer calibration procedure when set to the Custom position.
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The EEPROM will then be tested by reading the complete EEPROM to a checksum which will be compared to a checksum generate stored EEPROM. If an error is found the word "CAL " will be flashed on the HL display and the initialization process will continue.
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4.5.3 FREQUENCY SELECTOR This control operates as in the Normal Mode to select frequency to be calibrated. All frequencies must be calibrated and they can be calibrated in any sequence. 4.5.4 PRESENT BAR Present Bar controls the presentation of the stimulus.
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will be restored. If this error occurs the calibration process can be continued for other frequencies. 4.5.7 RESPONSE SWITCH This switch is not used during the transducer SPL Calibration Mode. Operations of the switch are not processed. 4.5.8 HL DISPLAY This display performs the dual function displaying the Calibration HL level and the SPL to which the transducer output level must be adjusted for correct calibration.
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4.6 CALIBRATION MODE EXIT Calibration Mode can be exited back to the Normal Mode Cal/Normal Switch at any time except for when default calibration data is being loaded. In this case the Calibration Mode is exited when the loading of default data is complete. When the Calibration Mode is...
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described The Dip Switches, located beneath the HL dial, will be in reverse numerical order. The reason for this is that they are will in the order in which we anticipate the frequency of usage 4.8.1 DIP SWITCH S4 IF DEFAULT DATA IS LOADED, DIAGNOSTIC MODE D4 PROCEDURE NOTE : MUST BE PERFORMED! DEFAULT CALIBRATION DATA...
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custom RTL values are stored in EEPROM by transducer type. The RTL values for a left transducer and a right transducer must be the same. The HL limits are directly affected by any changes in the RTL values. MODE INITIALIZATION instrument When Custom RTL selection mode is selected...
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Cal Option Dip Switch is used to switch from custom RTL calibration mode to the transducer SPL calibration mode. OTHER CONTROLS other controls, except the Cal/Normal Switch and Dip Switch inactive during this mode. Operations of other controls will not be processed. HL DISPLAY HL display is used to display the selected custom RTL value...
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4.9 SELECTION OF THE DIAGNOSTIC MODE CAL/NORMAL SWITCH This switch is used to select the operating mode of instrument. The Diagnostic Mode is entered by setting this switch to the Cal position while Cal Option Dip Switch #1 is in on position.
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When switched into the Diagnostic Mode HL display will display a code to indicate which diagnostic test is being selected. The codes are as follows: "DO " = Hardware Diagnostic Test "D1" = Pushbutton Diagnostic Test "D2 " = Display Diagnostic Test "D4"...
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ROUTING SWITCH stimulus is This switch selects the transducer to which routed just as in the Normal Mode. FREQUENCY KNOB frequency oscillator knob is used to select internal frequency and to control the stimulus multiplexer. When 125 Hz to 8000 Hz are selected on the knob, the internal oscillator is set for the frequency selected and the stimulus mux is set to the internal oscillator.
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displayed in a right justified, integer format on digits 1, 2 and RESPONSE LED This LED is not used during the hardware diagnostic test and will remain OFF. STIMULUS when stimulus is being LED is used to indicate This being LED is OFF when the stimulus is...
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DESCRIPTION OF CONTROLS In this test, the controls except the Cal/Normal Switch are used to select functions, but are only operated testing purposes. HL DISPLAY This display is used to display the keycodes as controls operated. The keycode will display on digits 1 and 2. LOW BATTERY SEGMENT This LCD segment will indicate a low battery voltage condition.
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4.9.3 DISPLAY DIAGNOSTIC TES TT (D2) TEST DESCRIPTION test provides a means of visually testing the operation of This code LCD segments and LEDS. When the test is selected, the 2 seconds. will be displayed on the HL display for "D2 "...
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4.9.4 A/D CONVERTER DIAGNOSTIC TEST (D3) TEST DESCRIPTION This test will provide a means to test the A/D converter channel used to measure the battery voltage. When this test is selected the A/D input will be sampled every msec and the converted value displayed on the HL display.
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EQUIPMENT REQUIRED Variable DC power supply, operating range of +6.5 Vdc to +7.5 Vdc minimum DVM. Adjust DC power supply to 7.5 Vdc then connect the negative terminal to TP100 and the positive terminal to TP101. Connect DVM to Audiometer Module TP1000 (LOW) and TP102 (HIGH).
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4.9.5 ATTENUATOR MAXIMUM OUTPUT LEVEL CALIBRATION (D4) Data loaded,this procedure must be Default NOTE: performed before calibration of earphones. TEST DISCR I P T I O N If the Microprocessor of the GSI 17 has been replaced or a major calibration data loss has occurred the Attenuator Maximum output When performing this calibration, the level must be calibrated.
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TEST INITIALIZATION into attenuator maximum output level When switched calibration the instrument will be initialized as follows: Tone Type = Current Selection Frequency = Current Selection Stimulus M = Oscillator Position Channel = OFF Attenuator Position = 255 +10 dB Pad = Out Transducer Routing = Current Selection HL Display = Displays "D4"...
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EXTENDED RANGE PUSHBUTTON (+10 dB PAD) ------ This pushbutton is used to store the calibration data in EEPROM. After the calibration data is stored the EEPROM checksum will be updated. If the calibration data can be stored properly after attempts, the word "CAL" will be flashed on HL and then the previously displayed value restored.
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CAUTION: STATIC SENSITIVE DEVICES - USE PROPER PRECAUTIONS WHEN HANDLING AND SERVICING. DISASSEMBLY INSTRUCTIONS Disconnect GSI 17 from power. (Battery Pack and/or Power Module). Disconnect and set aside all accessories. Remove 2 round control knobs, Item 1. Remove 3 slide switch caps, Item 2. Close top cover, Item 3.
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5.3 ACCESSORIES & REPLACEMENT PARTS Earphone, TDH-39P, 50 ohms 8000-0046 (1 Earphone Cushion, Type MX-41/AR 8000-0143 (1 Headband 8000-0142 Phone Cord Assembly (L and R) 4204-0147 Headphone Audiocups 8000-0155 Patch Cord, 2 Cond. 4204-0505 Audiogram Form, 1 pad of 50 1717-9600 Instruction Manual 1717-0100...
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DIAGNOSTIC MODE FUNCTION CONTROLS the Diagnostic Mode DO are as follows: Function controls for Same as Normal Operating Mode - Power Switch active at all times. This 3 position switch is active at F2 - L/R Routing Switch all times in the Diagnostic Mode. Left Position - Output is not routed a m p l i f i e r .
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6.2 OUTPUT RELATED TROUBLESHOOTING SYMPTOMS Symptom Possible Solution(s) Output failures Earphone Cord, Earphone, Patch Cord/Jack Panel - If applicable, Amplifier, Output Routing, Enable/Disable, Switch, Latch/Control Circuit. GENERAL APPROACH TO FAULT ISOLATION If the loss of output is isolated to only one of earphones then exchanging...
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6.3 LEFT OR RIGHT AMPLIFIER TROUBLESHOOTING SYMPTOMS (Refer to Figure 6-2: BLOCK DIAGRAM OF AMPLIFIER SIGNAL FLOW) ALL VOLTAGES MEASURED WITH THE CHANNEL ON, L OR R SELECTED ACCORDINGLY, 1 kH z FREQUENCY, OUTPUT LOADED. Check for signal presence/absences at the amplifier output pin U400 pin 5 - Right U401 pin 5 - Left This should be an undistorted si new ave of approximately 80 m vR M S.
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V REF C P U E C , Figure 6-3: BLOCK DIAGRAM OF ATTENUATOR SIGNAL FLOW 6.4 ATTENUATOR TROUBLESHOOTING HINTS BLOCK DIAGRAM OF ATTENUATOR SIGNAL FLOW) (Refer to Figure 6-3: Non linearity, no output, large shifts in output level. The VCA (U301) output is controlled by a dc voltage produced by the D/A converter (U303) The input to the converter is...
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following table to check various circuit voltages proper level. Table 6-l: ATTENUATOR CIRCUIT TEST CHECK NOTE: Voltage measurements with DAC value of 0, 1 kHz Frequency and Tone Steady. Measurement Location Expected Voltaqe Junction R314 & R316 (R Side) - Osc. out .2 VRMS 3.35 Vdc U303 3 Pin 15 - DAC Voltage Reference...
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OSCILLATOR TROUBLESHOOTING HINTS rule only test equipment carried service representatives is a Digital Volt Meter (DVM). oscillator circuitry generally difficult, if impossible to troubleshoot in the field using a DVM. Various power supply pins may be checked at specific IC's on the oscillator circuit output pins may be checked for "relative"...
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data lines. In this instance probe these lines with an oscilloscope and look for any address or data lines that are in- active (no data or periodic state transition). If an in-active line is found the processor may be at fault but the problem is most likely a bad port or latch somewhere on the bus.
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The current draw of the GSI 17 can be checked by connecting an ammeter in place of the power switch. The current draw in the active mode should be less than 75 ma. In the sleep mode the current draw should be reduced to approximately 16 ma. 6.8 TROUBLESHOOTING THE DISPLAY Refer to the Calibration Mode, Section 4, for method of entry into the Display Diagnostic Mode (D2).
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6.10 ERROR MESSAGES The GSI 17 will display a Diagnostic Error Message should a condition exist which may cause incorrect or unreliable operation I f an error is detected normal operation of of the instrument. the instrument will be aborted and the instrument will stop The condition of the error will be indicated to the operating.
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Probable Cause and Solution Error Code INVALID TONE SWITCH SETTING - If not recoverable replace S5 then U503. INVALID FREQUENCY SWITCH SETTING recoverable replace RE2 then U503. INVALID ROUTING SWITCH SETTING - If not recoverable replace S4 then U503. UNDEFINED KEY CODE ERROR - This error may occur with the failure of any front panel control.
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Error Code Probable Cause and Solution EEPROM CHECKSUM ERROR - Data in the Mirror Memory is in error. recoverable perform calibration. If the problem is not resolved by calibration replace U503. EPROM EEPROM DATA LOAD ERROR recoverable replace U503 then U505. CALIBRATION TYPE READ ERROR - Should occur only E28 &...
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7.1 ANALOG CIRCUIT A square wave at the desired frequency is generated by a timer internal to the microprocessor. This square wave is applied to the input of switched capacitor filters for smoothing into a sine wave. filter section is programmed as Low Pass frequencies except...
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8.1 GENERAL NOTES The Audiometer Board is a self-contained audiometric module. If the board is changed, the headphones must be calibrated to the board. If during the calibration process, default data is loaded then diagnostic mode D5 procedure must be performed (see Section 4, Calibration of this manual).
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once in each of 3 different blocks within the EEPROM. When a calibration point is requested, the appropriate location in each three blocks is read and decoded. For the data to be valid value from 2 of the 3 blocks must match.
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The Left/Right Control The FM/Pulsed/Steady Control The Subject Response Switch The Calibration/Normal Mode Switch The Calibration/Diagnostic Mode Dip Switch(s) INPUT/OUTPUT (I/O) PORT DESIGNATIONS Physical Signal Direction Port Name Description HL1 and HL2 form a 2 bit U503 PORT(A) code of the HL selector position.
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Physical Signal Direction Description Name Port PULSE PULSE and FM form the 2 U503 PORT(E) 4 bit code of the Tone Type switch position. PULSE Invalid - 0 Pulsed - 1 Steady - 1 Voltage Source Status BAT/LINE U503 PORT(D) 6 0=lINE Voltage l=Battery Voltage BATVOLT...
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Signal Physical Port Name Direction Description PRESENT Present Bar Status 0=Pressed 1=Released AFILHI Oscillator Antialiasing Filter Select AFILHI 50/100 BP/LP 125 Hz - 0 250 Hz - 0 500 Hz - 0 750 Hz - 0 1 KHz - 1 1.5KHz - 1 2 KHz - 1 3 KHz - 1...
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Signal U511 Timer Name Direction Description TMRO SQWIN 8254 Counter 0 Used for the Oscillator SWQIN Frequency = TMR1 SCFCLK Clock. Stimulus Frequency 8254 TMR2 CLKGEN Counter 1 Used for the Oscillator Switched Capacitor Filter SCFCLK. (see the following table 8254 Counter 2 Used to Produce the 2 msec Time- base.
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8.8 OUTPUT ROUTING AND POWER AMPLIFIERS Analog switches U402 and U403 are used to route the attenuated, and possibly range extended, signal to the left and right power amplifiers. CPU reads status of front panel left/right switch and controls the analog switches accordingly. use of two power amplifiers (U400, U401) as well as...
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8.11 ATTENUATOR AND 10 dB RANGE EXTENDER The attenuator (U301) is a voltage controlled amplifier. Although it does have amplification gain, the majority of its dynamic range is used as an attenuator. The total range of the attenuator is 112 dB which is adjustable using a variable dc voltage applied to Pin 3 (EC) of the device.
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Adjust R403 for minimum distortion. Minimum distortion should be less than 2% (THD). Check distortion at opposite earphone jack. If distortion at output cannot be adjusted to NOTE : less than 2%, remove 60 ohm load and recheck. reduces, power If distortion amplifiers may be at fault, if not, attenuator may be the cause.
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Description Ref. Desisnation Part No. No. MISCELLANEOUS ESD Director, LCD, .83" H. SHIELD 1 1717-8005 1717-8005 SHIELD 2 ESD Director, LCD, 0.83" H. SHIELD 3 ESD Shield, Switch, .45" H. 1717-8010 TP100 thru TP102 Jumper, Test Point 5080-0001 EPROM, Programmed 1717-0500 U505 Crystal, 4 MHz, Low Profile...
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10.1 DESCRIPTION The GSI 17 can be operated via battery power with the 1717-2010 This battery pack can be used with the GSI- battery option. supplied rechargeable NiCad pack (8410-0060) or with commercially available size C alkaline batteries. (See Figure 10-3 for an illustration of the battery pack).
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Connect the battery pack power cord (A) to the power cord receptacle on the rear panel of the audiometer. For line power operation (mains) or recharging, connect the instrument power cord (B) to the receptacle on the lower edge of the battery pack (perpendicular to the (See Figure 10-2).
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indication, and the controls will not function. To restore operation, the batteries must be recharged for up to 18 hours (full charge), or AC power (mains) may be used. If the audiometer is operated via AC power (mains) with the rechargeable batteries in place, some battery charging will occur.
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7044-0037 17 17-0406 Figure 10-3: NiCad B A T T E R Y O P E R A T I O N...
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10.5 NiCad BATTERY ASSEMBLY PARTS LIST 1717-2010 Description Part No. Base, Battery 1717-7004 Cover, Battery 1717-7005 Label, Battery Compartment 1717-0442 Assembly, Battery Charge Board 1717-4710 Screw, Locking 6-32 x .375 lg. 7044-0037 Screw, Pan Hd., 6-32 x .750 lg. 7044-1205 Battery Pack, GSI 17, NiCad 8410-0060 Assembly, Battery Contact Board, Top...
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M O D U L E PARTS LIST QUANTITY PART NUHBER REFERENCE DESCRIPTION FUSE, 3110 AMP 5433- 102 1 LT350, REGULATOR, ADJ. DIODE, IN4151 6082- 100 I Cl, c2, c3 C A P , 1 uf, 35 v, 10% 4450-4301 RESISTOR, 1.24 K ohm 6350- 1124...
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