Test Report DSC

FCC ID: MRXGG4

Test Report

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FCCID_1809987

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

Contents
1 Test Specifications, General Procedures, and Location 3
1.1 Test Specification and General Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Test Location and Equipment Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2 Configuration and Identification of the Equipment Under Test 5
2.1 Description and Declarations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.1 EUT Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.3 Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.4 Test Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.5 Functional Exerciser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.6 Modifications Made . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.7 Production Intent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.8 Declared Exemptions and Additional Product Notes . . . . . . . . . . . . . . . . . . . . . . . . 6

3 Emissions 7
3.1 General Test Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1.1 Radiated Test Setup and Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1.2 Conducted Emissions Test Setup and Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1.3 Power Supply Variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1.4 Thermal Variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Intentional Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2.1 Fundamental Emission Pulsed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2.2 Fundamental Emission Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.2.3 Fundamental Emission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.3 Unintentional Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.3.1 Transmit Chain Spurious Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

List of Tables
1 Willow Run Test Labs, LLC Equipment List. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2 EUT Declarations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3 Pulsed Emission Characteristics (Duty Cycle). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4 Intentional Emission Bandwidth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5 Fundamental Radiated Emissions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6 Transmit Chain Spurious Emissions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

List of Figures
1 Photos of EUT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 EUT Test Configuration Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 Radiated Emissions Diagram of the EUT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 Radiated Emissions Test Setup Photograph(s). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5 Pulsed Emission Characteristics (Duty Cycle). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5 Pulsed Emission Characteristics (Duty Cycle). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6 Intentional Emission Bandwidth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 2 of 14

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

Schrader Electronics
TPMS
FCC ID: MRXGG4
IC: 2546A-GG4

Figure 2: EUT Test Configuration Diagram.

2.1.3 Variants
There is only a single variant of the EUT, as tested. Normal samples were actuated for worst case on time, worst
case emission bandwidth, and CW mode. Please see the description of operation exhibit supplied with this filing
detailing the operating modes of this device.

2.1.4 Test Samples
Three samples in total were provided. Two normal samples capable of normal, test, and CW mode activation. One
sample un-potted for testing and photographs.

2.1.5 Functional Exerciser
The EUT was interrogated by a manufacturer supplied LF tool to observe the learn mode of operation, and was
shaken to observe the roll-mode of operation.

2.1.6 Modifications Made
There were no modifications made to the EUT by this laboratory.

2.1.7 Production Intent
The EUT appears to be a production ready sample.

2.1.8 Declared Exemptions and Additional Product Notes
The EUT is permanently installed in a transportation vehicle. As such, digital emissions are exempt from US and
Canadian digital emissions regulations (per FCC 15.103(a) and IC correspondence on ICES-003).
The EUT also employs some modes of operation that alert the vehicle user of sudden changes in tire pressure.
Such alert modes fall under FCC 15.231(a)(4), and may operate during the pendency of the alarm condition. A
detailed list of all operating modes is included in the Description of Operation exhibit included in this application.

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 6 of 14

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

3 Emissions
3.1 General Test Procedures
3.1.1 Radiated Test Setup and Procedures
Radiated electromagnetic emissions from the EUT are first evaluated in our shielded fully anechoic chamber. Spec-
trum and modulation characteristics of all emissions are recorded, and emissions above 1 GHz are fully characterized.
The anechoic chamber contains a set-up similar to that of our outdoor 3-meter site, with a turntable and antenna
mast. Instrumentation, including spectrum analyzers and other test equipment as detailed in Section 1.2 are em-
ployed. After indoor pre-scans, emission measurements up to 1 GHz are made on our outdoor 3-meter Open Area
Test Site (OATS). If the EUT connects to auxiliary equipment and is table or floor standing, the configurations
prescribed in ANSI C63.4 / CISPR 22 are followed. Alternatively, a layout closest to normal use (as declared by the
provider) is employed if the resulting emissions appear to be worst-case in such a configuration. See Figure 3.

Long Interface Cables
EUT Power Long Interface Cables
(to AUX) AUX Power
(to EUT)

Equipment Under Test Auxiliary
(EUT)
Short Interface Cables Equipment
(AUX)

Radiated Emissions Table

Figure 3: Radiated Emissions Diagram of the EUT.

All intentionally radiating elements are placed on the test table lying flat, on their side, and on their end (3-axes)
and the resulting worst case emissions are recorded. For both horizontal and vertical polarizations, the test antenna
is raised and lowered from 1 to 4 m in height until a maximum emission level is detected. The EUT is then rotated
through 360o in azimuth until the highest emission is detected. The test antenna is then raised and lowered one last
time from 1 to 4 m and the worst case value is recorded. Photographs of the test setup employed are depicted in
Figure 4.
If the EUT exhibits spurious emissions due to internal receiver circuitry, such emissions are measured with an
appropriate carrier signal applied. For devices with intentional emissions below 30 MHz, a shielded loop antenna
is used as the test antenna. It is placed at a 1 meter receive height and appropriate low frequency magnetic field
extrapolation to the regulatory limit distance is employed. Emissions between 30 MHz and 1 GHz are measured
using tuned dipoles and/or calibrated broadband antennas. Emissions above 1 GHz are characterized using standard
gain horn antennas. Care is taken to ensure that test receiver resolution and video bandwidths meet the regulatory
requirements, and that the emission bandwidth of the EUT is not reduced.
Where regulations allow for direct measurement of field strength, power values (dBm) measured on the test
receiver / analyzer are converted to dBµV/m at the regulatory distance, using
Edist = 107 + PR + KA − KG + KE − CF
where PR is the power recorded on spectrum analyzer, in dBm, KA is the test antenna factor in dB/m, KG is the
combined pre-amplifier gain and cable loss in dB, KE is duty correction factor (when applicable) in dB, and CF is
a distance conversion (employed only if limits are specified at alternate distance) in dB. This field strength value is
then compared with the regulatory limit. If effective isotropic radiated power (EIRP) is compute, it is computed as
EIRP (dBm) = E3m (dBµV /m) − 95.2.

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 7 of 14

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

3.1.2 Conducted Emissions Test Setup and Procedures
Battery Power Conducted Spurious The EUT is not subject to power line conducted emissions measurements
when it is powered solely by its internal battery.

3.1.3 Power Supply Variation
Tests at extreme supply voltages are made if required by the the procedures specified in the test standard, and results
of this testing are detailed in this report.
In the case the EUT is designed for operation from a lead-acid battery power source, the extreme test voltages
are evaluated between 90% and 130% of the nominal battery voltage declared by the manufacturer. For float charge
applications using gel-cell type batteries, extreme test voltages are evaluated between 85% and 115% of the nominal
battery voltage declared. For all battery operated equipment, worst case intentional and spurious emissions are
re-checked employing a new (fully charged) battery.

3.1.4 Thermal Variation
Tests at extreme temperatures are made if required by the procedures specified in the test standard, and results of
this testing are detailed in this report. The provider has declared that the EUT is designed for operation over the
temperature range −40o C to +85o C. Before any temperature measurements are made, the equipment is allowed to
reach a thermal balance in the test chamber, temperature and humidity are recorded, and thermal balance is verified
via a thermocouple based probe.

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 9 of 14

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

3.2 Intentional Emissions
3.2.1 Fundamental Emission Pulsed Operation
The details and results of testing the EUT for pulsed operation are summarized in Table 3. Plots showing the
measurements made to obtain these values are provided in Figure 5.

Table 3: Pulsed Emission Characteristics (Duty Cycle).
Test Date: 21-Sep-12
Detector IF Bandwidth Video Bandwidth Test Engineer: Joseph Brunett
Pk 1 MHz 3 MHz Meas Distance: 10 cm

FCC/IC
Overall Transmission Internal Frame Characteristics Computed
Min. Max. Total Min. Duty Cycle
Repetition No. of Transmission Max. Frame Frame
# EUT Test Mode* Rate (sec) Frames Length (sec) Length (ms) Period (ms) Frame Encoding (%) (dB)
Each ASK frame is 28.5 ms in duration with
no less than 100 ms period. All frames
LF Activated contain a leading range of regular wake
1 "LEARN" mode. Single 16 2.15 28.5000 100.0 pulses/bits followed by a period of 14.25 -16.9
See Figure (a) Manchester encoded bits. All encoded data
follows a Manchester encoding dut of 0.1204
ms on time in a 0.2408 ms period.

Worst-case
2 Rolling Mode. 30 6 < 1.0 28.5000 100.0 same as above 14.25 -16.9
See Figure (b)

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 10 of 14

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

3.2.3 Fundamental Emission
Following the test procedures listed in Section 1.1, radiated emissions measurements are made on the EUT for both
Horizontal and Vertical polarized fields. Table 5 details the results of these measurements.

Table 5: Fundamental Radiated Emissions.
Frequency Range Det IF Bandwidth Video Bandwidth Test Date: 21-Sep-12
25 MHz ≤ f ≤ 1 000 MHz Pk/QPk 120 kHz 300 kHz Test Engineer: Joseph Brunett
f > 1 000 MHz Pk 3 MHz 3MHz EUT Mode: CW
f > 1 000 MHz Avg 3 MHz 10kHz Meas. Distance: 3 meters

FCC/IC
Freq. Ant. Ant. Pr (Pk) Pr (Avg)* Ka Kg E3(Pk) E3(Avg)FCC/IC E3(Avg Pass
# MHz Used Pol. dBm dBm dB/m dB dBµV/m dBµV/m Lim. dBµV/m dB Comments
1 Sample No.: TX1
2 433.9 Dip H -28.7 -45.6 21.5 21.5 78.3 61.4 72.9 11.5 (fresh battery)
3 433.9 Dip V -28.9 -45.8 21.5 21.5 78.1 61.2 72.9 11.7
4
5
6
Freq. DC Supply Relative Pr (Pk)
# MHz Voltage dBm**
7 433.9 2.50 -30.8
8 433.9 2.75 -29.2
9 433.9 3.00 -28.7
10 433.9 3.25 -28.2
11 433.9 3.50 -27.0
*Avg data computed from Peak Measured Data and EUT Duty Cycle. EUT in CW mode.
** EUT in CW mode.

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 13 of 14

Date of Issue: September 28, 2012 Prepared For: Schrader Electronics Limited Test Report No.: 20120928-01

3.3 Unintentional Emissions
3.3.1 Transmit Chain Spurious Emissions
The results for the measurement of transmit chain spurious emissions at the nominal voltage and temperature are
provided in Table 6. Measurements are performed to 10 times the highest fundamental operating frequency.

Table 6: Transmit Chain Spurious Emissions.
Frequency Range Det IF Bandwidth Video Bandwidth Test Date: 21-Sep-12
25 MHz ≤ f ≤ 1 000 MHz Pk/QPk 120 kHz 300 kHz Test Engineer: Joseph Brunett
f > 1 000 MHz Pk 1 MHz 3 MHz EUT Mode: CW
f > 1 000 MHz Avg 1 MHz 10kHz Meas. Distance: 3 meters

Transmitter Unintentional Spurious Emissions FCC/IC
Freq. Ant. Ant. Pr (Pk) Pr (Avg)* Ka Kg E3(Pk) E3(Avg) FCC/IC E3lim (Avg) Pass
# MHz Used Pol. dBm dBm dB/m dB dBµV/m dBµV/m dBµV/m dB Comments
1 Sample# Tx1
2 867.8 Dip H -67.7 -84.6 27.8 18.1 49.0 32.1 52.9 20.8 flat (IFBW = 3 kHz)
3 867.8 Dip V -75.1 -92.0 27.8 18.1 41.6 24.7 52.9 28.2 end (IFBW = 3 kHz)
4 1301.7 R-Horn H -48.3 -65.2 20.7 23.7 55.7 38.8 54.0 15.1 max all
5 1735.6 R-Horn H -47.9 -64.8 21.9 30.7 50.3 33.4 54.0 20.6 max all
6 2169.5 R-Horn H -42.5 -59.4 22.9 31.0 56.3 39.4 54.0 14.5 max all
7 2603.4 R-Horn H -49.8 -66.7 24.1 29.5 51.8 34.9 54.0 19.1 max all
8 3037.3 R-Horn H -50.2 -67.1 25.5 27.9 54.3 37.4 54.0 16.5 max all
9 3471.2 R-Horn H -54.6 -71.5 26.8 26.4 52.8 35.9 54.0 18.0 max all
10 3905.1 R-Horn H -62.4 -79.3 28.1 24.8 48.0 31.1 54.0 22.9 max all
11 4339.0 R-Horn H -58.3 -75.2 29.5 22.9 55.2 38.3 54.0 15.7 max all, noise
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
*Avg data computed from Peak Measured Data and EUT Duty Cycle. EUT in CW mode.

Willow Run Test Labs, LLC, 8501 Beck Road, Building 2227, Belleville, Michigan 48111 USA Page 14 of 14

Document Created: 2012-10-07 21:46:40
Document Modified: 2012-10-07 21:46:40

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