Welch Allyn Grason-Stadler GSI 17 1717-9700, Service Manual

Page 1: ...Covers Welch Allyn AM232 Audiometer ...

Page 2: ...r travel expense at the service center s current rate NOTE Changes in the product not approved in writing by Grason Stadler shall void this warranty Grason Stadler shall not be liable for any indirect special or consequential damages even if notice has been given in advance of the possibility of such damages THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDING BUT NOT LIMI...

Page 3: ...hanical Dimensions 1 14 Material Used in Manufacture 1 15 Leakage Test 1 16 Headband Static Force 1 17 Earphone Cushion Attenuation 1 18 Accessories SECTION 2 FUNCTIONAL DESCRIPTION Figure 2 l Connectors Controls Indicators 2 1 Front Panel Controls and Indicators 2 2 Rear Panel Connectors and Controls 2 3 General Operation of Controls 2 4 Power Up Initialization 2 5 Sleep Mode SECTION 3 ROUTINE MA...

Page 4: ...Mode Hardware Diagnostic Test DO Pushbutton Diagnostic Test D1 Display Diagnostic Test D2 A D Converter Diagnostic Test D3 1 1 1 1 Attenuator Maximum Output Level Calibration D4 4 2 4 2 1 4 2 2 4 3 4 4 4 5 4 5 1 4 5 2 4 5 3 4 5 4 4 5 5 4 5 6 4 5 7 4 5 8 4 5 9 4 5 10 4 5 11 4 5 12 4 6 4 7 4 8 4 8 1 4 8 2 4 8 3 4 8 4 4 9 4 9 1 4 9 2 4 9 3 4 9 4 4 9 5 SECTION 5 DISASSEMBLY 5 1 5 2 5 3 Figure 5 l Disa...

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Page 9: ... CMOS HANDLING PRECAUTIONS Many of the integrated circuits on the P C boards are CMOS and NMOS type CAUTION Failure to observe the following precautions whenever a circuit board or an integrated circuit package is handled can result in damage to the GSI 17 a Place instrument and parts on a grounded conductive work surface b Ground yourself with a strap having about 1 M ohm resistance C Ground the ...

Page 10: ...duction transducers TDH39 Earphones This instrument meets ANSI S3 6 and IEC 645 Type 4 Audiometer Standards The GSI 17 is designed to meet current revisions of the following standards and specifications for audiometers ANSI S3 6 IEC 645 IS0 389 IEC 601 1 3 TEST STIMULUS PURE TONE SPECIFICATIONS A pure tone is the only stimulus source for this audiometer DISCRETE FREQUENCIES 125 250 500 750 1000 15...

Page 11: ...lly in dB HL 1 6 TONE SWITCH This electronic switch turns the stimulus signal ON OFF with minimal audible distortion MODES Normal State Activated State Stimulus OFF Stimulus ON RISE FALL TIME 20 50 ms Measured at the 1 dB and 20 dB points on the signal envelope ON OFF RAT IO With the Tone Switch OFF the output will be at least 10 dB below standard reference equivalent threshold for any 1 3 octave ...

Page 12: ...the first and last pulse will have 200 ms on time DUTY CYCLE 50 RISE FALL TIME 20 50 ms ON OFF RATIO BETWEEN PULSES 20 dB FREQUENCY MODULATION FM Rate 5 Hz FM Deviation 25 1 8 TRANSDUCERS HEADSET TDH39 Earphones with 60 ohm impedance 1 9 FRONT PANEL CONTROLS AND REAR PANEL CONNECTORS FRONT PANEL CONTROLS Frequency Selection HL Select Mode Selector Pulsed Steady FM Routing Left Right Present Bar Po...

Page 13: ...w 0 Volts SUBJECT SWITCH J7 Pin Function Output Voltaqe Tip Switch High 5 Vdc Sleeve Switch Low 0 Volts POWER INPUT J1 Power Module Battery Power Connected No Power w NiCad Module Battery P i n Name Attached Installed J1 1 VSUP NC NC J1 2 CHASGND PROTECTIVE PROTECTIVE GND GND Jl 3 CGND 0 REF 0 REF Jl 4 BAT LINE 2 6 to 3 0 3 7 to 4 3 J1 5 VBAT 7 3 to 9 0 7 0 to 9 0 All values listed are in Volts DC...

Page 14: ...INS VOLTAGE VARIATION lo LINE MAINS FREQUENCY RANGE 50 60 Hz LINE MAINS FREQUENCY VARIATION 5 1 11 BATTERY PACK VOLTAGE BATTERY VOLTAGE OPERATING RANGE 7 0 v to 9 0 v BATTERY PACK TYPICAL OPERATING LIFE NiCad 22 Hours Alkaline 45 Hours 1 12 ENVIRONMENTAL CONDITIONS OPERATING TEMPERATURE RANGE 15 to 40 Degrees Celsius SHELF TEMPERATURE RANGE Power Module Operated 40 to 60 Degrees Celsius Battery Op...

Page 15: ...ryl SE 100J Flame Retardant 1 15 LEAKAGE TEST AC CONNECTED SAFETY TEST Leakage Current 25 uamps High Voltage Breakdown 115 V operation 3000 v 220 V operation 4000 v 1 16 HEADBAND STATIC FORCE 1 6 to 2 0 pounds when earcups are 5 7 inches apart Measured with distance center of headband to center of earphones equal to 5 inches 1 17 EARPHONE CUSHION ATTENUATION Frequency Hz Attenuation 125 6 5 250 4 ...

Page 16: ... serial numbers below 0856 require a different power module See Section 9 Power Module for details Optional Catalog Numbers Response Handswitch Patch Cord 2 Conductor Audiocups Battery Pack Assembly Battery Pack includes GSI supplied NiCad Battery May also be used with six 6 Size C Alkaline Batteries not included Replacement NiCad Battery 8000 0175 1717 9600 1717 0100 1717 2010 8000 0240 8000 0241...

Page 17: ...R 3 P io R 5 Figure 2 1 CONNECTORS CONTROLS INDICATORS 8 ...

Page 18: ...Level indicated on LCD F4 Present Bar for stimulus presentation F5 Loudspeaker in operation as such Actual presentation indicated by illuminated LED F6 Subject response indicator LED shows the operator that the test subject has pressed the handswitch button F7 Frequency control for setting stimulus frequency Frequency indicated in window adjacent to control F8 Routing switch for routing the stimul...

Page 19: ... LCD segment All polled controls are checked every 12 msec for a change in state All operations of all controls are debounced for 12 msec before processing The Extended Range pushbutton operates by a push ON push OFF manner The Present Bar and Response Switch operate by a press and hold manner except in the Calibration and Diagnostic modes where the Present Bar is push ON push OFF When a press and...

Page 20: ...ns All analog hardware will be initialized according to these selections After initialization the instrument will remain idle with all controls active 2 5 SLEEP MODE The GSI 17 has a mode which is designed to lengthen battery life When the unit has been left on under battery power without operation for more than 5 minutes the GSI 17 will enter the Sleep Mode It is important to emphasize that this ...

Page 21: ...trument set on 1000 Hz move the HL control F2 from 0 to 60 dB and listen for low frequency hum 60 to 120 Hz and random noise hiss or low rushing sound at all attenuator levels Some audible random noise at levels above 60 dB is permissible Below 60 d B however only the signal should be audible Any of these noises can be confused with the signal by naive subjects and affect the accuracy of the audio...

Page 22: ... the transducer i e left earphone or 3000 Hz will restore normal instrument function As is the case with any instrument malfunction a certified service technician should be contacted immediately Remember to make note of the combination of transducer and frequency which resulted in the CAL message 3 4 2 Exx When an error code consisting of an E and a 2 digit number xx number appears on the audiomet...

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Page 25: ... D3 this section 6 Attenuator maximum output level calibration See Diagnostic Mode D4 this section e Proceed with Transducer Calibration a Select Calibration Mode using Cal Norm Switch b Select Frequency and Reference HL for calibration C Select Earphone Routing L or R d Turn Tone ON using Present Bar NOTE Display will update to the ANSI SPL required for proper calibration subtract or add micropho...

Page 26: ...NORMAL CAL MODE SWITCH NORM CAL R404 LINEARITY ADJUST LR403 DISTORTION ADJUST DIP SWITCH S2 SQUARE PORT 1 POSITION l POSITION 4 t Figure 4 2 ACCESS TO CALIBRATION CONTROLS 18 ...

Page 27: ...tion Mode consists of two modes The Custom SPL Selection Mode allows the selection of customized SPL values for alternate transducers The Transducer SPL Calibration Mode is used to calibrate the sound pressure level SPL of each stimulus for each transducer 4 2 1 CAL NORMAL SWITCH This switch is used to select the operating mode of the instrument The Calibration Mode is entered by setting this swit...

Page 28: ...ode 4 3 CALIBRATION MODE ENTRY The Calibration Mode can be entered via the Cal Normal Switch at any time except during the power up initialization phase or when a stimulus is being presented In these cases the Cal Mode will be entered when the initialization is complete or the stimulus turned off The indication that the instrument is in the Calibration Mode will be the non integer value in the for...

Page 29: ...nt selection HL Display Current custom SPL level stored in EEPROM Response LED OFF Stimulus On LED OFF Low Battery Segment Current state Segment OFF 4 5 EARPHONE SPL CALIBRATION MODE This Calibration Mode is used to calibrate the SPL for each stimulus for each transducer This is done by adjusting the selected transducer output SPL level to the specified value displayed on the HL display This SPL v...

Page 30: ... range of the calibration HL will be from the nonextended 10 dB range maximum HL limit to 20 dB below the limit Operation of the selector to select levels outside of this range are invalid When this occurs the level will default to the limit and the HL display will be flashed 3 While the stimulus is on the HL selector dial will adjust the transducer output level to allow the SPL level to be adjust...

Page 31: ... the current transducer and frequency and does not indicate correction for the sound level meter frequency response 4 5 9 RESPONSE LED This LED is used to indicate the correct storage of calibration data in the EEPROM when the Extended Range Pushbutton is operated This LED is normally OFF and will be turned ON for 2 seconds after the calibration data has been stored and verified If the data is not...

Page 32: ...bit is stored 3 times once in each of 3 different blocks within the EEPROM with a different format in each of the 3 blocks When a specific data bit is required the appropriate location in each of the 3 blocks is read and decoded For the data to be valid the value from 2 of the 3 blocks must match This method will allow for the detection of data errors and the correction of some errors If a calibra...

Page 33: ...ata consists of the standard GSI RTL values for the transducer types supplied with the instrument Custom RTL vs GSI RTL selection status This will default to the GSI RTL selection Attenuator 2 5 V maximum output level limit This will default to an attenuator limit for each stimulus Checksum The EEPROM checksum is calculated using the contents of the EEPROM after all default data has been stored 4 ...

Page 34: ...ckwise step The transducer output level attenuator position does not follow changes to the custom RTL value The allowable range of the custom RTL value is 63 5 dB SPL Operation of the knob to select levels outside of this range will not be allowed If this occurs the displayed custom RTL value will remain the same and will flash temporarily FREQUENCY SELECTOR Selects the frequency for which the cus...

Page 35: ...is LED indicates when the custom RTL value has been stored successfully in the EEPROM by turning on for 2 seconds OTHER DISPLAYS All other LEDs and LCD segments are not used and will remain off 4 8 3 DIP SWITCH S2 NOT USED Exception when in Diagnostic Mode Dip Switch 1 4 8 4 DIP SWITCH S1 DIAGNOSTIC MODE The Diagnostic Mode provides direct control over the hardware components which may not be avai...

Page 36: ...bration Mode reset the Dip Switches to select the new test and then re enter the Calibration Mode Switch Function OFF down ON up S1 Diagnostic Mode OFF Selected Enters the Diagnostic Mode when the Cal Normal Switch is set to Cal s2 S3 These switches are used to s4 select the diagnostic test to be performed when the Diagnostic Mode is entered as follows Switch Setting Diagnostic Test S1 s2 s3 s4 Se...

Page 37: ...d Position Transducer Routing Each hardware block is controlled independent of all other blocks i e selecting an oscillator frequency will not change the attenuator position TEST INITIALIZATION When switched into the hardware diagnostic test the instrument will be initialized as follows Tone Type Current Selection Frequency Current Selection Stimulus MUX Oscillator or External input based on curre...

Page 38: ... Bar is operated a second time The 10 dB pad will not be affected by turning the stimulus ON or OFF HL SELECTOR This knob is used to directly set the attenuator position The position will be adjusted by 0 5 dB 1 step for each clockwise step of the knob and by 0 5 dB for each counter clockwise step of the knob The allowable range of the attenuator position will be from 0 to 255 When either of these...

Page 39: ...ON DIAGNOSTIC TEST D1 TEST DESCRIPTION This test provides a means of testing all controls except for the Cal Normal Switch for proper operation when manually operated While in this test the operation of any control will display the keycode of the new position of the control on the HL display This keycode will be displayed until another control is operated TEST INITIALIZATION When switched into the...

Page 40: ...low battery voltage condition ALL OTHER DISPLAYS All other seqments and LEDs are not used during this test and will remain OFF DISPLAY CODES FOR PUSHBUTTON SWITCH SELECTIONS Control Left Right Pulsed FM Steady 125 Hz 250 Hz 500 Hz 750 Hz 1000 Hz 1500 Hz 2000 Hz 3000 Hz 4000 Hz 6000 Hz 8000 Hz Code Key 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 Freq Position 12 Response Switch Press Release Ex...

Page 41: ...he test During this test the low battery voltage monitoring will not be performed since the display is not available to indicate a low battery condition TEST INITIALIZATION When switched into the display diagnostic test the instrument will be initialized as follows Tone Type Current selection Frequency Current selection Stimulus MUX Current position Channel OFF Attenuator position 255 10 dB Pad Ou...

Page 42: ...controls except the Cal Normal switch and Extended Range Pushbutton are inactive during this diagnostic test Operations of all other controls will be ignored EXTENDED RANGE PUSHBUTTON This pushbutton is used to store the A D values in the EEPROM for LO Bat detection and instrument shutdown Instrument shutdown will occur when the battery voltage is too low to safely operate the GSI 17 circuitry Whe...

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Page 45: ...ating proper storage of data into memory It is important that the 10 dB button is pressed only once If L2 is displayed exit Cal Mode return to Step 5 and repeat procedure 7 Adjust the DC power supply voltage to 7 0 Vdc 50 mV Store this A D value into memory by pressing the 10 dB Range Extender Button The display will momentarily display L2 indicating proper storage of data into memory 8 Adjust DC ...

Page 46: ... is measured The calibration data is then stored and the process is repeated for all remaining stimuli The stimuli may be calibrated in any order but all must be calibrated Originally all output levels were adjusted to 2 5 vrms 15 vrms for each frequency The newer GSI 17 s have specific maximum output levels for calibration Serial numbers and output levels are outlined below NOTE When performing t...

Page 47: ...This knob selects the stimulus to be calibrated Its operation is the same as in the Normal Mode PRESENT BAR _ _ The Present Bar controls the presentation of the stimulus It operates in a push ON push OFF manner so if it is operated pressed and released when the stimulus is OFF the stimulus will be presented and will remain ON until the Present Bar is operated a second time The 10 dB pad will not b...

Page 48: ...e HL selector It will be displayed in a right justified integer format on digits 1 2 and 3 LED RESPONSE This LED is used to indicate the correct storage of calibration data in the EEPROM when the Extended Range Pushbutton is operated This LED is normally OFF and will be turned ON for 2 seconds after the calibration data has been stored and verified If the data is not stored correctly the LED will ...

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Page 51: ...front panel and printed circuit board Items 7 and 8 away from bottom case Item 4 Remove screw Item 9 in back of printed circuit board 5 2 PARTS NUMBERS ITEM NUMBER DESCRIPTION 1 HL Frequency Knobs 2 Slide Switch Caps Power L R Tone Type 3 Top Cover blank no labels 4 Bottom Case blank no labels 5 6 Screws 6 6 Screws 7 Front Panel blank no labels 8 Printed Circuit Board 9 6 Screws 10 Front Panel Lab...

Page 52: ...of 50 Instruction Manual Service Manual Replacement NiCad Pack Label Consult Manual Label H L Recess GSI 17 Label Coverr _ AUDIOMETER Label Power Label 601 CLASSB2 Label Adjustmentt A I A 8000 0220 n I 12 VDk l 200 MA 8000 0046 1 ea 8000 0143 1 ea 8000 0142 4204 0147 8000 0155 4204 0505 1717 9600 1717 0100 1717 0110 8410 0060 1717 0425 1717 0426 1717 0410 1717 0415 1717 0420 1717 0430 ...

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Page 55: ...ecific DAC level F5 10 dB Range Extender Active at all times this Push ON Push OFF selection allows the operator to change the state of the 10 dB range extender indicator of LCD indicates the Range Extender is active F6 Present Bar Active at all times this Push ON Push OFF selection allows the operator to turn the channel OFF and ON The channel OFF ON is accomplished using the attenuator It is imp...

Page 56: ...th the original earphone then the assembly is at fault earphone If the earphone assembly is found to be defective first check the set screws and assure that they are tightened securely If the screws are loose a problem similar to this would result If the screws are secure try exchanging the left and right earphone cords assure that the earphone serial numbers are legible if not mark the earphones ...

Page 57: ...of approximately 80 m vRM S If the input signal is present here but not present at the amplifier output pin then the amplifier may be defective First check the amplifier enable line U400 pin 1 Right U401 pin 1 Left for a logic 0 5 Vdc A logic 1 5 Vdc disables the amplifier for muting or to conserve power If a logic 0 is present then verify that the 5 Vdc and 5 Vdc power supplies are present If amp...

Page 58: ...attenuator circuit is not present at the output routing circuit check the following NOTE Calibration data is used to update the latch circuit Assure that the calibration data is appropriate or select Diagnostic Mode DO In Diagnostic Mode DO the display will indicate a DAC value of 255 all bits at the latch output should equal 5 Vdc and the attenuator should be at max attenuation Turning the HL kno...

Page 59: ... U303 3 Pin 15 DAC Voltage Reference 3 35 Vdc Tone OFF U303 3 Pins 4 thru 11 5 5 Vdc 0 Vdc U302 2 Pin 7 3 4 Vdc 0 Vdc U300 0 Pin 7 5 Vdc 15 5 Vdc U300 0 Pin 1 0 VRMS 1 2 VRMS Junction R313 R311 R Side 3 4 Vdc 0 Vdc 10 dB Range Extender Check Pad OUT Pad In U300 0 Pin 1 DAC 0 1 2 VRMS 3 5 VRMS DAC 10 7 VRMS 2 1 VRMS Sine Wave should have clipping evident on negative and positive slopes Increasing D...

Page 60: ... located on the Analog Board Schematic 1 The oscillator output is routed to the attenuator circuitry via the Filter Multiplexer U 200 The Filter Multiplexer routes the appropriate signal to the input of the attenuator circuit This signal is either the oscillator output Band Pass filtered BP Low Pass filtered LP or a test signal input The antialliasing filters round the edges of the square wave clo...

Page 61: ...ation It is important to note that this problem could also occur if a data error was present in the EEPROM portion of the processor 6 7 POWER SUPPLY RELATED PROBLEMS The GSI 17 is powered by battery or by the Power Module Battery Eliminator AC Adapter When a power supply is suspected to be defective first check the power source Have the batteries been replaced Were the batteries new Dated Is the p...

Page 62: ...Plane When the two signals present at the LCD segment are in phase there is no potential across the segment and the segment is OFF When the two signals are out of phase there is 5 V potential present a all times and the segment is ON Generally if a segment is missing an AC meter can be used to check for proper phase relative to the Back Plane An AC measurement of 5 V would indicate the signals are...

Page 63: ... will display a Diagnostic Error Message should a condition exist which may cause incorrect or unreliable operation of the instrument I f an error is detected normal operation of the instrument will be aborted and the instrument will stop operating The condition of the error will be indicated to the operator by displaying an abort code on digit s 1 2 and 3 of the HL Display The error message will ...

Page 64: ... position and remove the jumper wire If the problem still exists replace the processor U503 and repeat the above procedure El2 E20 E21 E22 E23 E24 E25 LOW VOLTAGE ERROR Battery Low Shut Down adjustment is not set to within the acceptable range If not recoverable perform Battery Low Shut Down Calibration Calibration Section 4 9 4 If the problem still exists replace U503 and repeat procedure CALIBRA...

Page 65: ...n 4 9 4 If the problem persists replace U503 BATTERY WARNING LEVEL READ ERROR If not recoverable perform Battery Low Shut Down Calibration Calibration Section 4 9 4 If problem persists replace U503 STACK OVERFLOW ERROR Should always be recoverable If the error persists replace U503 or U505 BAD POINTER TO EEPROM ROUTINES If not recoverable replace U505 then U503 INVALID KEY CODE ERROR If not recove...

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Page 68: ...he input of the output routing switches The switches apply the signal to either the left or right power amplifier however it is never applied to both simultaneously The left and right power amplifiers in turn drive the left and right earphones 7 2 DIGITAL CIRCUIT The heart of the digital circuitry is a MC 68HC11A1 microcomputer This CPU was chosen for its flexibility and low power consumption Func...

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Page 70: ...heral functions include Eight channel analog to digital A D converter with eight bit resolution of which two channels PE6 and PE7 are used to monitor battery functions Free running timer system that has three input capture lines Two lines PAO and PA1 are used to decode HL direction and amount of change on an edge triggered basis The third input capture line PA2 is used to detect left vs right outp...

Page 71: ...ata storage is not lost when power is removed from the device 8 4 TIMER U511 There is a programmable timer chip which is used for 3 different functions via 3 programmable outputs One output is the square wave SQWIN which ultimately gets filtered into the pure tone used for presentation into the earphones A second output is the clock SCFCLK for setting the switched capacitor filter 3 dB points Thes...

Page 72: ... 1 1 Position 2 1 0 Position 3 0 0 Position 4 0 1 LEFT and UNUSED form the 2 bit code of the Routing Switch position UNUSED LEFT Invalid 0 0 Unused 0 1 Right 1 0 Left 1 1 Not Used Not Used 10 dB Extended Range Pad control 0 Pad Out 1 Pad In Range Extended Not Used See Bit 2 LEFT U503 PORT E 3 FREQ1 IN FREQ1 FREQ4 form the 4 bit 2 FREQ2 IN code of the Frequency 1 FREQ3 IN Selector position 0 FREQ4 ...

Page 73: ...tatus 0 lINE Voltage l Battery Voltage Analog Battery Voltage input to the A D converter SCI Received Data SCI Transmitted Data SPI Input Not Used SPI Data to Display Driver SPI Clock to Display Driver Sleep Mode Status O Awake 1 In Sleep Mode Dip Switch 1 Diag Cal Mode O ON Enter Diag Mode l OFF Enter Cal Mode Dip Switch 2 Spare Dip Switch 3 GSI User SPL O ON User SPL Mode 1 OFF GSI SPL Mode Dip ...

Page 74: ... Hz 0 0 0 250 Hz 0 0 0 500 Hz 0 0 0 750 Hz 0 0 0 1 KHz 1 0 0 1 5KHz 1 0 0 2 KHz 1 0 0 3 KHz 1 0 0 4 KHz 1 1 0 6 KHz 1 1 0 8 KHz 1 1 1 Oscillator Clock Scale Select see AFILHI for States Oscillator Digital Filter Type Select see AFILHI for States External Input MUX control 0 Select External Input 1 Select Oscillator Channel ON LED Control 0 LED OFF 1 LED ON Response LED Control 0 LED OFF 1 LED ON R...

Page 75: ...6 00 1 6000 8000 00 400 000 10 00 1 8000 8000 00 400 000 10 00 1 Signal Name Direction Description Antialiasing AAFIL BP State LP 0 0 0 0 0 0 0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 1 8 7 DISPLAY LCD The LCD is a reflective 3 1 2 digit Liquid Crystal Display It is the largest indicator on the GSI 17 and it is used for a variety of purposes Some purposes are indication of HL and possible error messages in th...

Page 76: ... to converter U101 where through its switched capacitor circuitry is inverted to 7 Volts The unregulated negative voltage is then applied to the 5 Volt regulator U100 Note that the voltage converter is disabled shutdown whenever the sleep mode is entered This is accomplished via controls switched through U202 8 10 OSCILLATOR The oscillator is comprised of the following IC s and their functions U20...

Page 77: ...eference Threshold Value RTV to a resolution of dB The amplifier stage U300 following the attenuator has a switchable feedback resistor This stage serves as the 10 dB range extender circuit used during normal operation The gain of the stage is changed by switching Resistor R304 in parallel with R303 or grounding R304 at one end 10 dB position 8 12 POTENTIOMETER ADJUSTMENT PROCEDURES L LINEARITY AD...

Page 78: ...ay be the cause 8 13 SUGGESTED REPAIR PARTS 1717 4700ROT Audiometer Board Rotating Stock 1717 9610 Parts Kit Note The following parts are included in this kit Qty GSI Part Number Description 3 7874 0173 1 7874 0172 1 7874 0171 1 7874 0175 1 7874 0170 1 5437 1275 1 1717 3810 2 4214 0155 1 4204 0147 1 1717 9610 AS Slide Switch Power L R Tone Type HL Switch Frequency Switch Cal Norm Switch 4 Position...

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Page 85: ... 1 of 8 Decode Demux IC 74HC273 Octal D Flip Flop IC 74HC373 Tri State Octal Latch IC 74HC244 Octal Buffer Driver See U507 IC 82C54 Prog Timer 5431 9012 5432 7003 5432 1120 5432 1117 5433 1020 5431 9017 5431 3000 5431 3138 5431 3273 5431 3373 5431 3244 CR1 and CR2 CR3 CR5 CR100 CR101 CR102 CR500 LED HLMP 0504 Green Square Diode 1N4151 See CR3 Diode Zener SA11A Diode 1N4004 Diode 1N5817 See CR3 RES...

Page 86: ...0 See R304 Res Film 90 9K 1 4W 1 5 Res Film 130 Ohm 1 4W 1 See R200 Pot Comp 50K 20 25 Turn Pot Comp 1K 10 25 Turn See R200 See R314 Res Film 332 Ohm 1 4W 1 See R314 Res Comp 47K 5 See R314 Res Film 499 Ohm 1 4W 1 Res Comp 10M 1 4W 1 See R310 Res Film 24 3K 1 4W 1 See R314 See R502 Res Network 47K x 9 2 Res Network 10K x 9 22 See RPSOO See RP501 See RPSOO Res Network 100K x 8 2 Cap Tant 47 u F 20 ...

Page 87: ... C205 See C102 Cap Cer 68 pF 10 100V Cap Cer 1 0 uF 20 80 50V See C103 Cap Cer 0 47 uF 20 80 5ov See C102 See C306 See C104 See C102 See C104 See C102 See C104 See C306 See C104 Cap Cer 47 pF 10 100V See C104 See C102 Cap Cer 22 pF 10 100V Cap Cer 10 pF 10 100V See C102 See C1303 See C102 See C303 See C205 Conn Pow Input 5 Pin Din Socket Jack Earphone Handswitch PC Mtg See J4 Conn 6 Pin Female Tel...

Page 88: ...tion ESD Director LCD 83 H ESD Director LCD 0 83 H ESD Shield Switch 45 H Jumper Test Point EPROM Programmed Crystal 4 MHz Low Profile Switch Slide ON OFF L R FM Steady Pulse Spacer LED Insulator Crystal Part No No 1717 8005 1717 8005 1717 8010 5080 0001 1717 0500 5075 0045 7874 0173 7574 0205 7574 0210 80 ...

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Page 94: ...rage cavity of the audiometer On the bottom of the storage cavity located close to one side are four 4 indentations These are thin sections of the case which must be punctured to provide entry holes for the four screws See Figure 10 l Before installing the battery pack be sure the instrument is turned off and unplugged from the AC power mains outlet Unplug the power cord the earphone jacks and the...

Page 95: ...Figure 10 2 BATTERY POWER CONNECTION 88 ...

Page 96: ...argeable NiCad batteries will occur if the pack is left charging for more than the 18 hours required for a full charge the batteries should not be left charging for extended periods i e several days because the useful life of the rechargeable NiCad pack will be shortened Lucas GSI recommends unplugging the battery pack power input cord from the rear of the audiometer and plugging the main line pow...

Page 97: ...l the alkaline batteries first remove the battery pack cover by removing the two screws that hold it in place then lift off the cover Carefully pull the NiCad batteries out of the pack they are wrapped in plastic and will come out of the pack as a single unit Carefully disconnect the lead wires of the NiCad batteries from the battery compartment by disconnecting the small plug connector You will n...

Page 98: ... v7044 0037 17 17 0406 Figure 10 3 NiCad BATTERY OPERATION 9 1 ...

Page 99: ...FUNCTIONAL DESCRIPTION The Battery Charger Board serves several purposes When connected to the GSI 17 the charger board relay connects the battery voltage to the GSI 17 power input When a power module is connected to the Battery Charger Board the applied voltage energizes the relay which connects the charger board regulated voltage to the GSI 17 power input The charger board voltage regulator U1 L...

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Page 101: ... Film 1K 25W 1 Res Film 10 Ohm 25W 1 Res Film 78 7 Ohm 25W 1 Res Film 1 33K 25W 1 Res Film 4 99K 2 5 W 1 Res Film 15K 25W 1 Res Film 40 2K 25W 1 See R3 Cl Cap Tant 10 uF 20V 20 FUSE F1 Fuse 0 63 Amp SLO BLO RELAY K1 Relay Spdt 9V 6090 1530 MISCELLANEOUS J1 Conn 5 Pin Din Male 4230 4025 Assembly Cable Battery 1717 2020 Clamp Insulated 4 4314 0030 Heat Sink Low Profile 5415 1070 Clip Fuse 5650 0200 ...

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Page 104: ...475 CABLE ASSEMBLY BATTERY 1717 2020 POWER MODULE 1 17 V 8000 0220 BREAD BOARD 4260 1360 CONNECTOR MALE DIN P C MOUNT 4230 4025 CLIP FUSE HOLDER 5640 1800 NUT HEX LOCKING 4 40 5814 0001 SCREW PAN HEAD 4 40 x 3 8 7044 1103 KNOB 5504 0080 LED with mounting hardware 6084 1050 POTENTIOMETER 2 K ohm 6004 0090 RADIO SHACK MODEL 270 283 PROJECT BOX or equiv P1 I 1 consisting of q 5 1K 1 4 W L 0 X CABLE 4...