Test Report HAC T-Coil

FCC ID: IHDT56XS2

Test Report

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         HAC T-COIL TEST REPORT                                                         Report No. : HA930825B




         HEARING AID COMPATIBILITY
            T-COIL TEST REPORT
          FCC ID              : IHDT56XS2
          Equipment           : Mobile Cellular Phone
          Brand Name          : Motorola
          T-Rating            : T4
          Applicant    : Motorola Mobility LLC
                         222 W,Merchandise Mart Plaza, Chicago IL 60654 USA
          Manufacturer : Motorola Mobility LLC
                         222 W,Merchandise Mart Plaza, Chicago IL 60654 USA
          Standard     : FCC 47 CFR §20.19
                         ANSI C63.19-2011


      The product was received on Jan. 07, 2019 and testing was started from Jan. 08, 2019 and
      completed on Jan. 09, 2019. We, SPORTON INTERNATIONAL INC., would like to declare
      that the tested sample has been evaluated in accordance with the test procedures and has
      been in compliance with the applicable technical standards.

      The report must not be used by the client to claim product certification, approval, or
      endorsement by TAF or any agency of government.

      The test results in this variant report apply exclusively to the tested model / sample.
      Without     written   approval of     SPORTON      INTERNATIONAL INC.        EMC       &   Wireless
      Communications Laboratory, the test report shall not be reproduced except in full.




            Approved by: Cona Huang / Deputy Manager



SPORTON INTERNATIONAL INC. EMC & Wireless Communications Laboratory
                       No. 52, Huaya 1st Rd., Guishan Dist., Taoyuan City, Taiwan (R.O.C.)




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FAX : 886-3-328-4978                                                               Issued Date : Apr. 22, 2019
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              HAC T-COIL TEST REPORT                                                                                                          Report No. : HA930825B

                                                                Table of Contents
1.  Attestation of Test Results ........................................................................................................................................ 4
2.  General Information ................................................................................................................................................... 5
3.  Testing Location......................................................................................................................................................... 6
4.  Applied Standards ..................................................................................................................................................... 6
5.  Air Interface and Operating Mode............................................................................................................................. 7
6.  Measurement standards for T-Coil ........................................................................................................................... 8
    6.1     Frequency Response ....................................................................................................................................... 8
    6.2     T-Coil Signal Quality Categories ....................................................................................................................... 8
7. T-Coil Test Procedure ................................................................................................................................................ 9
    7.1     Test Flow Chart................................................................................................................................................10
    7.2     Test Setup Diagram ......................................................................................................................................... 11
    7.3     Description of EUT Test Position .....................................................................................................................13
8. Test Equipment List ..................................................................................................................................................14
9. T-Coil testing for OTT VoIP Application ..................................................................................................................14
10. Uncertainty Assessment ..........................................................................................................................................15
11. References .................................................................................................................................................................16

Appendix A. Plots of T-Coil Measurement
Appendix B. DASY Calibration Certificate




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FAX : 886-3-328-4978                                                                                                                  Issued Date : Apr. 22, 2019
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         HAC T-COIL TEST REPORT                                       Report No. : HA930825B


                        History of this test report
       Report No.      Version                     Description                Issued Date

       HA930825B       Rev. 01    Initial issue of report                     Apr. 22, 2019




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          HAC T-COIL TEST REPORT                                                              Report No. : HA930825B

1. Attestation of Test Results
                                                                             Frequency                 Magnetic
     Air Interface           Band MHz                T-Rating
                                                                             Response                   Intensity
   OTT over EDGE            EDGE1900                   T4                      Pass                       Pass
     Date Tested                                                2019/03/13
The device is compliance with HAC limits specified in guidelines FCC 47CFR §20.19 and ANSI Standard ANSI C63.19.

Reviewed by: Jason Wang
Report Producer: Daisy Peng




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FAX : 886-3-328-4978                                                                     Issued Date : Apr. 22, 2019
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         HAC T-COIL TEST REPORT                                                            Report No. : HA930825B
2. General Information
                                         Product Feature & Specification
Applicant Name          Motorola Mobility LLC
Equipment Name          Mobile Cellular Phone
Brand Name              Motorola
FCC ID                  IHDT56XS2
HW Version              DVT2
SW Version              PPF29.58
EUT Stage               Identical Prototype
                        GSM850: 824.2 MHz ~ 848.8 MHz
                        GSM1900: 1850.2 MHz ~ 1909.8 MHz
                        WCDMA Band II: 1852.4 MHz ~ 1907.6 MHz
                        WCDMA Band IV: 1712.4 MHz ~ 1752.6 MHz
                        WCDMA Band V: 826.4 MHz ~ 846.6 MHz
                        CDMA2000 BC0: 824.7 MHz ~ 848.31 MHz
                        CDMA 2000 BC1: 1851.25 MHz ~ 1908.75 MHz
                        CDMA 2000 BC10: 817.9 MHz ~ 823.1 MHz
                        LTE Band 2: 1850.7 MHz ~ 1909.3 MHz
                        LTE Band 4: 1710.7 MHz ~ 1754.3 MHz
                        LTE Band 5: 824.7 MHz ~ 848.3 MHz
                        LTE Band 7: 2502.5 MHz ~ 2567.5 MHz
                        LTE Band 12: 699.7 MHz ~ 715.3 MHz
                        LTE Band 13: 779.5 MHz ~ 784.5 MHz
Frequency Band          LTE Band 17: 706.5 MHz ~ 713.5 MHz
                        LTE Band 25: 1850.7 MHz ~ 1914.3 MHz
                        LTE Band 26: 814.7 MHz ~ 848.3 MHz
                        LTE Band 30: 2307.5 MHz ~ 2312.5 MHz
                        LTE Band 38: 2572.5 MHz ~ 2617.5 MHz
                        LTE Band 41: 2498.5 MHz ~ 2687.5 MHz
                        LTE Band 66: 1710.7 MHz ~ 1779.3 MHz
                        LTE Band 71: 665.5 MHz ~ 695.5 MHz
                        WLAN 2.4GHz Band: 2412 MHz ~ 2462 MHz
                        WLAN 5.2GHz Band: 5180 MHz ~ 5240 MHz
                        WLAN 5.3GHz Band: 5260 MHz ~ 5320 MHz
                        WLAN 5.5GHz Band: 5500 MHz ~ 5720 MHz
                        WLAN 5.8GHz Band: 5745 MHz ~ 5825 MHz
                        Bluetooth: 2402 MHz ~ 2480 MHz
                        NFC: 13.56 MHz
                        GSM/GPRS/EGPRS
                        AMR / RMC 12.2Kbps
                        HSDPA
                        HSUPA
                        DC-HSDPA
Mode
                        CDMA2000 : 1xRTT/1xEv-Do(Rel.0)/1xEv-Do(Rev.A)
                        LTE: QPSK, 16QAM, 64QAM
                        802.11a/b/g/n/ac HT20/HT40/VHT20/VHT40/VHT80
                        Bluetooth BR/EDR/LE
                        NFC:ASK
Remark:
1. Added 2nd source included verification worst found in original report, Sporton RF Emissions test report, number
   HA8D2726B, FCC ID: IHDT56XS2.




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FAX : 886-3-328-4978                                                                  Issued Date : Apr. 22, 2019
Form version: 181113


            HAC T-COIL TEST REPORT                                                            Report No. : HA930825B


3. Testing Location
Sporton Lab is accredited to ISO 17025 by Taiwan Accreditation Foundation (TAF code: 1190) and the FCC designation
No. TW1190 under the FCC 2.948(e) by Mutual Recognition Agreement (MRA) in FCC test.

                                                Testing Laboratory
Test Site                          SPORTON INTERNATIONAL INC.
                                   No. 52, Huaya 1st Rd., Guishan Dist., Taoyuan City, Taiwan (R.O.C.)
Test Site Location                 TEL: +886-3-327-3456
                                   FAX: +886-3-328-4978
                                   Sporton Site No.:
Test Site No.
                                   SAR04-HY




4. Applied Standards
‧    FCC CFR47 Part 20.19
‧    ANSI C63.19 2011-version
‧    FCC KDB 285076 D01 HAC Guidance v05
‧    FCC KDB 285076 D02 T Coil testing v03
‧    FCC KDB 285076 D03 HAC FAQ v01




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FAX : 886-3-328-4978                                                                    Issued Date : Apr. 22, 2019
Form version: 181113


            HAC T-COIL TEST REPORT                                                                Report No. : HA930825B
5. Air Interface and Operating Mode
   Air                                         C63.19              Simultaneous               Name of Voice          Power
Interface      Band MHz            Type
                                               Tested                Transmitter                Service             Reduction
                GSM850                                               WLAN, BT                                          No
                                    VO           Yes                                           CMRS Voice
                GSM1900                                              WLAN, BT                                          No
  GSM
                EDGE850
                                    VD           Yes                 WLAN, BT                 Google Duo(1)            No
               EDGE1900
                WCDMA II                                             WLAN, BT                                          No
               WCDMA IV             VO           Yes                 WLAN, BT                  CMRS Voice              No
 UMTS
               WCDMA V                                               WLAN, BT                                          No
                  HSPA              VD           Yes                 WLAN, BT                 Google Duo(1)            No
                   BC0                                               WLAN, BT                                          No
                   BC1              VO           Yes                 WLAN, BT                  CMRS Voice              No
 CDMA
                  BC10                                               WLAN, BT                                          No
                                                                                                              (1)
                  EVDO              VD           Yes                 WLAN, BT                 Google Duo               No
                 Band 2                                              WLAN, BT                                          No
                 Band 4                                              WLAN, BT                                          No
                 Band 5                                              WLAN, BT                                          No
                 Band 7                                              WLAN, BT                                          No
                 Band 12                                             WLAN, BT                                          No
                 Band 13                                             WLAN, BT                   VoLTE                  No
   LTE
                                    VD           Yes                                               /
  (FDD)          Band 17                                             WLAN, BT                                          No
                                                                                              Google Duo(1)
                 Band 25                                             WLAN, BT                                          No
                 Band 26                                             WLAN, BT                                          No
                 Band 30                                             WLAN, BT                                          No
                 Band 66                                             WLAN, BT                                          No
                 Band 71                                             WLAN, BT                                          No
                 Band 38                                             WLAN, BT                   VoLTE                  No
   LTE
                                    VD           Yes                                               /
  (TDD)          Band 41                                             WLAN, BT                                          No
                                                                                              Google Duo(1)
                  2450                                                                                                 No
                  5200                                                                          VoWiFi  (1)            No
  Wi-Fi           5300              VD           Yes          GSM,WCDMA,CDMA,LTE                   /                   No
                  5500                                                                        Google Duo(1)            No
                  5800                                                                                                 No
   BT              2450               DT           No          GSM,WCDMA,CDMA,LTE                   NA               No
Type Transport:
VO= Voice only
DT= Digital Transport only (no voice)
VD= CMRS and IP Voice Service over Digital Transport
Remark:
1. For protocols not listed in Table 7.1 of ANSI C63.19-2011 or the ANSI C63.19-2011 VoLTE interpretation, the average
    speech level of −20 dBm0 should be used.




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         HAC T-COIL TEST REPORT                                                             Report No. : HA930825B
6. Measurement standards for T-Coil
6.1 Frequency Response
The frequency response of the perpendicular component of the magnetic field, measured in 1/3 octave bands, shall
follow the response curve specified in this sub-clause, over the frequency range 300 Hz to 3000 Hz.
Figure 1.1 and Figure 1.2 provide the boundaries as a function of frequency. These response curves are for true
field-strength measurements of the T-Coil signal. Thus, the 6 dB/octave probe response has been corrected from
the raw readings.




            Fig. 1.1 Magnetic field frequency response for WDs with field strength≤-15dB at 1 KHz




     Fig. 1.2 Magnetic field frequency response for WDs with a field that exceeds –15 dB(A/m) at 1 kHz



6.2 T-Coil Signal Quality Categories
This section provides the signal quality requirement for the intended T-Coil signal from a WD. Only the RF immunity
of the hearing aid is measured in T-Coil mode. It is assumed that a hearing aid can have no immunity to an
interference signal in the audio band, which is the intended reception band for this mode. A device is assessed
beginning by determining the category of the RF environment in the area of the T-Coil source.
The RF measurements made for the T-Coil evaluation are used to assign the category T1 through T4. The limitation
is given in Table 1. This establishes the RF environment presented by the WD to a hearing aid.
                                                                   Telephone parameters WD signal quality
                         Category
                                                                     ((signal + noise) to noise ratio in dB)
                        Category T1                                                 0 to 10 dB
                        Category T2                                                10 to 20 dB
                        Category T3                                                20 to 30 dB
                        Category T4                                                   > 30 dB
                                  Table 1 T-Coil Signal Quality Categories




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FAX : 886-3-328-4978                                                                   Issued Date : Apr. 22, 2019
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         HAC T-COIL TEST REPORT                                                                 Report No. : HA930825B
7. T-Coil Test Procedure
Referenced to ANSI C63.19-2011, Section 7.4,
This section describes the procedures used to measure the ABM (T-Coil) performance of the WD. In addition to
measuring the absolute signal levels, the A-weighted magnitude of the unintended signal shall also be determined.
To assure that the required signal quality is measured, the measurement of the intended signal and the
measurement of the unintended signal must be made at the same location for each measurement position. In
addition, the RF field strength at each measurement location must be at or below that required for the assigned
category.
Measurements shall not include undesired properties from the WD's RF field; therefore, use of a coaxial connection
to a base station simulator or non-radiating load, there might still be RF leakage from the WD, which can interfere
with the desired measurement. Pre-measurement checks should be made to avoid this possibility. All
measurements shall be performed with the WD operating on battery power with an appropriate normal speech
audio signal input level given in ANSI C63.19-2011 Table 7.1. If the device display can be turned off during a phone
call, then that may be done during the measurement as well,
Measurement shall be performed at two locations specified in ANSI C63.19-2011 A.3, with the correct probe
orientation for a particular location, in a multistage sequence by first measuring the field intensity of the desired
T-Coil signal the same location as the desired ABM or T-Coil signal (ABM1), and the ratio of desired to undesired
magnetic components (ABM2) must be measured at the same location as the desired ABM or T-Coil signal (ABM1),
and the ratio of desired to undesired ABM signals must be calculated. For the perpendicular field location, only the
ABM1 frequency response shall be determined in a third measurement stage.
The following steps summarize the basic test flow for determining ABM1 and ABM2. These steps assume that a
sine wave or narrowband 1/3 octave signal can be used for the measurement of ABM1.
a. A validation of the test setup and instrumentation may be performed using a TMFS or Helmholtz coil Measure
     the emissions and confirm that they are within the specified tolerance.
b. Position the WD in the test setup and connect the WD RF connector to a base station simulator or a
     non-radiating load. Confirm that equipment that requires calibration has been calibrated, and that the noise
     level meets the requirements given in ANSI C63.19-2011 clause 7.3.1.
c. The drive level to the WD ise set such that the reference input level specified in ANSI C63.19-2011 Table 7.1 is
     input to the base station simulator (or manufacturer's test mode equivalent) in 1 kHz, 1/3 octave band. This
     drive level shall be used for the T-Coil signal test (ABM1) at f = 1 kHz. Either a sine wave at 1025 Hz or a
     voice-like signal, band-limited to the 1 kHz 1/3 octave, as defined in ANSI C63.19-2011 clause 7.4.2, shall be
     used for the reference audio signal. If interference is found at 1025 Hz an alternative nearby reference audio
     signal frequency may be used. The same drive level shall be used for the ABM1 frequency response
     measurements at each 1/3 octave band center frequency. The WD volume control may be set at any level up to
     maximum, provided that a signal at any frequency at maximum modulation would not result in clipping or signal
     overload.
d. Determine the magnetic measurement locations for the WD device (A.3), if not already specified by the
     manufacturer, as described in ANSI C63.19-2011 clause 7.4.4.1.1 and 7.4.4.2.
e. At each measurement location, measure and record the desired T-Coil magnetic signals (ABM1 at fi) as
     described in ANSI C63.19-2011 clause 7.4.4.2 in each individual ISO 266-1975 R10 standard 1/3 octave band.
     The desired audio band input frequency (fi) shall be centered in each 1/3 octave band maintaining the same
     drive level as determined in item c) and the reading taken for that band.
f. Equivalent methods of determining the frequency response may also be employed, such as fast Fourier
     transform (FFT) analysis using noise excitation or input-output comparison using simulated speech. The
     full-band integrated probe output, as specified in D.9, may be used, as long as the appropriate calibration curve
     is applied to the measured result, so as to yield an accurate measurement of the field magnitude. (The resulting
     measurement shall be an accurate measurement in dB A/m.)
g. All Measurements of the desired signal shall be shown to be of the desired signal and not of an undesired
     signal. This may be shown by turning the desired signal ON and OFF with the probe measuring the same
     location. If the scanning method is used the scans shall show that all measurement points selected for the
     ABM1 measurement meet the ambient and test system noise criteria in ANSI C63.19-2011 clause 7.3.1.
h. At the measurement location for each orientation, measure and record the undesired broadband audio
     magnetic signal (ABM2) as specified in ANSI C63.19-2011 clause 7.4.4.4 with no audio signal applied (or digital
     zero applied, if appropriate) using A-weighting and the half-band integrator. Calculate the ratio of the desired to
     undesired signal strength (i,e., signal quality).
i. Obtain the data from the postprocessor, SEMCAD, and determine the category that properly classifies the
     signal quality based on ANSI C63.19-2011 Table 8.5.




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FAX : 886-3-328-4978                                                                      Issued Date : Apr. 22, 2019
Form version: 181113


       HAC T-COIL TEST REPORT                                     Report No. : HA930825B
7.1 Test Flow Chart




                       Fig. 2 T-Coil Signal Test flowchart




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       HAC T-COIL TEST REPORT                                                         Report No. : HA930825B
7.2 Test Setup Diagram




General Note:
1. Define the all applicable input audio level as below according to C63 and KDB 285076 D02v03:
   - OTT VoIP input Level: -20dBm0
2. The test setup used for Google DUO VoIP call is via the data application unit on CMW500 connection to
   the Internet, also connection to the other auxiliary VoIP unit which is used to configure the audio codec
   and bit rate and also monitor the audio input level of -20dBm0.




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FAX : 886-3-328-4978                                                             Issued Date : Apr. 22, 2019
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            HAC T-COIL TEST REPORT                                                                     Report No. : HA930825B
1.     The Required gain factor for the specific signal shall typically be multiplied by this factor to achieve approx. the same
       level as for the 1kHz sine signal
2.     The below calculation formula is an example and showing how to determine the input level for the device.




Calculation formula:
- Audio Level at -16dBm0 = ((-16dBm0) – (3.14dBm0)) + X dBv
- Calculated Gain at -16dBm0 = 10(( audio level at -16dBm0 – Y dBm0) / 20) * 10
- Gatting setting at -16dBm0 = required gain factor * calculated gain
     Gain Value           20* log(gain)          AMCC Coil In             Level
        (linear)                dB                 (dBv RMS)              dBm0
                                                       -2.47               3.14
           10                   20                    -19.85             -14.24
          8.17                18.24                   -21.61                -16

                                      Duration         Peak to RMS            RMS           Required Gain        Calculated
           Signal Type
                                        (s)               (dB)                (dB)             Factor           Gain Setting
            1kHz sine                    -                  3                   0                 1                 8.17
         48k_voice_1kHz                  1                16.2                -12.7             4.33               35.36
     48k_voice_300Hz ~ 3kHz              2                21.6                -18.6             8.48               69.25




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FAX : 886-3-328-4978                                                                             Issued Date : Apr. 22, 2019
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       HAC T-COIL TEST REPORT                                                                Report No. : HA930825B
7.3 Description of EUT Test Position
    Fig.3 illustrate the references and reference plane that shall be used in a typical EUT emissions
    measurement. The principle of this section is applied to EUT with similar geometry. Please refer to
    Appendix C for the setup photographs.

           The area is 5 cm by 5 cm.
           The area is centered on the audio frequency output transducer of the EUT.
           The area is in a reference plane, which is defined as the planar area that contains the highest point
            in the area of the phone that normally rests against the user’s ear. It is parallel to the centerline of
            the receiver area of the phone and is defined by the points of the receiver-end of the EUT handset,
            which, in normal handset use, rest against the ear.
           The measurement plane is parallel to, and 10 mm in front of, the reference plane.




                       Fig.3 A typical EUT reference and plane for T-Coil measurements




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               HAC T-COIL TEST REPORT                                                                             Report No. : HA930825B
     8. Test Equipment List
                                                                                                                       Calibration
      Manufacturer                 Name of Equipment                    Type/Model       Serial Number
                                                                                                               Last Cal.        Due Date
         SPEAG               Audio Magnetic 1D Field Probe                AM1DV3              3130           Nov. 20, 2018    Nov. 19, 2019
         SPEAG                  Data Acquisition Electronics                  DAE4            854            Jun. 14, 2018    Jun. 13, 2019
         SPEAG               Audio Magnetic Calibration Coil                  AMCC            1049               NCR                 NCR
         SPEAG                  Audio Measuring Instrument                    AMMI            1041               NCR                 NCR
         SPEAG                      Test Arch Phantom                          N/A            N/A                NCR                 NCR
         SPEAG                         Phone Positioner                        N/A            N/A                NCR                 NCR
        RCPTWN                          Thermometer                           HTC-1         TM685-1          Nov. 12, 2018    Nov. 11, 2019
           R&S                      Base Station                          CMW500             115793          May. 24, 2018    May. 23, 2019
     Note:
     1. NCR: “No-Calibration Required”




     9. T-Coil testing for OTT VoIP Application
                                                                                                             Ambient  Freq.
                                                                      ABM1      ABM2     Signal
Plot                                                       Probe                                      T       Noise Response Frequency
     Air Interface       Mode            Channel                       dB        dB      Quality
No.                                                       Position                                  Rating      dB   Variation Response
                                                                      (A/m)     (A/m)      dB
                                                                                                              (A/m)     dB
                                                          Axial (Z)   -1.30     -40.89   39.59        T4      -50.33
 1    GSM1900        EDGE 2 Tx slots        661                                                                        1.33      Pass
                                                    Transversal (Y)   -6.35     -45.34   38.99        T4      -50.22

          Remark:
           1. Phone Condition: Mute on; Backlight off; Max Volume
           2. The detail frequency response results please refer to appendix A.
           3. Test Engineer:Nick Yu.




     TEL : 886-3-327-3456                                                                                           Page : 14 of 16
     FAX : 886-3-328-4978                                                                                    Issued Date : Apr. 22, 2019
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          HAC T-COIL TEST REPORT                                                                 Report No. : HA930825B
10. Uncertainty Assessment
The evaluation of uncertainly by the statistical analysis of a series of observations is termed a Type A
evaluation of uncertainty. The evaluation of uncertainty by means other than the statistical analysis of a series
of observation is termed a Type B evaluation of uncertainty. Each component of uncertainty, however
evaluated, is represented by an estimated standard deviation, termed standard uncertainty, which is
determined by the positive square root of the estimated variance. The combined standard uncertainty of the
measurement result represents the estimated standard deviation of the result. It is obtained by combining the
individual standard uncertainties of both Type A and Type B evaluation using the usual “root-sum-squares”
(RSS) methods of combining standard deviations by taking the positive square root of the estimated
variances. Expanded uncertainty is a measure of uncertainty that defines an interval about the measurement
result within which the measured value is confidently believed to lie. It is obtained by multiplying the combined
standard uncertainty by a coverage factor. For purpose of this document, a coverage factor two is used, which
corresponds to confidence interval of about 95 %. The DASY uncertainty Budget is showed in Table 8.2.
The judgment of conformity in the report is based on the measurement results excluding the measurement
uncertainty.

                                Uncertainty                                                      Standard       Standard
                                  Value         Probability                   Ci       Ci
      Error Description                                           Divisor                       Uncertainty    Uncertainty
                                                Distribution                (ABM1)   (ABM2)
                                  (±%)                                                           (ABM1)         (ABM2)
                                                     Probe Sensitivity
       Reference Level             3.0            Normal              1       1        1         ± 3.0 %         ± 3.0 %
      AMCC Geometry                0.4          Rectangular           √3      1        1         ± 0.2 %         ± 0.2 %
       AMCC Current                1.0          Rectangular           √3      1        1         ± 0.6 %         ± 0.6 %
   Probe Positioning During
                                   0.1          Rectangular           √3      1        1         ± 0.1 %         ± 0.1 %
          Calibrate
      Noise Contribution           0.7          Rectangular           √3    0.0143     1         ± 0.0 %         ± 0.4 %
      Frequency Slope              5.9          Rectangular           √3     0.1       1         ± 0.3 %         ± 3.5 %
                                                      Probe System
     Repeatability / Drift         1.0          Rectangular           √3      1        1         ± 0.6 %         ± 0.6 %
  Linearity / Dynamic Range        0.6          Rectangular           √3      1        1         ± 0.4 %         ± 0.4 %
       Acoustic Noise              1.0          Rectangular           √3     0.1       1         ± 0.1 %         ± 0.6 %
         Probe Angle               2.3          Rectangular           √3      1        1         ± 1.4 %         ± 1.4 %
     Spectral Processing           0.9          Rectangular           √3      1        1         ± 0.5 %         ± 0.5 %
       Integration Time            0.6            Normal              1       1        5         ± 0.6 %         ± 3.0 %
      Field Disturbation           0.2          Rectangular           √3      1        1         ± 0.1 %         ± 0.1 %
                                                        Test Signal
  Reference Signal Spectral
                                   0.6          Rectangular           √3      0        1         ± 0.0 %         ± 0.4 %
         Response
                                                        Positioning
      Probe Positioning            1.9          Rectangular           √3      1        1         ± 1.1 %         ± 1.1 %
     Phantom Thickness             0.9          Rectangular           √3      1        1         ± 0.5 %         ± 0.5 %
       EUT Positioning             1.9          Rectangular           √3      1        1         ± 1.1 %         ± 1.1 %
                                                  External Contributions
       RF Interference             0.0          Rectangular           √3      1       0.3        ± 0.0 %         ± 0.0 %
    Test Signal Variation          2.0          Rectangular           √3      1        1         ± 1.2 %         ± 1.2 %
                               Combined Standard Uncertainty                                     ± 4.1 %         ± 6.1 %
                                  Coverage Factor for 95 %                                                 K=2
                                    Expanded Uncertainty                                         ± 8.1 %         ± 12.3 %

                       Table 8.2 Uncertainty Budget of audio band magnetic measurement




TEL : 886-3-327-3456                                                                               Page : 15 of 16
FAX : 886-3-328-4978                                                                        Issued Date : Apr. 22, 2019
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         HAC T-COIL TEST REPORT                                                     Report No. : HA930825B

11. References
 [1]   ANSI C63.19-2011, “American National Standard for Methods of Measurement of Compatibility
       between Wireless Communications Devices and Hearing Aids”, 27 May 2011.
 [2]   FCC KDB 285076 D01v05, “Equipment Authorization Guidance for Hearing Aid Compatibility”, Sep
       2017
 [3]   FCC KDB 285076 D02v03, “Guidance for performing T-Coil tests for air interfaces supporting voice
       over IP (e.g., LTE and WiFi) to support CMRS based telephone services”, Sep 2017
 [4]   FCC KDB 285076 D03v01, “Hearing aid compatibility frequently asked questions”, Sep 2017
 [5]   SPEAG DASY System Handbook




TEL : 886-3-327-3456                                                                  Page : 16 of 16
FAX : 886-3-328-4978                                                           Issued Date : Apr. 22, 2019
Form version: 181113



Document Created: 2019-05-30 23:29:58
Document Modified: 2019-05-30 23:29:58

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