Test Report Part 1

FCC ID: AJK8221468

Test Report

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FCCID_176104

TEST REPORT – EXHIBIT F PART 1

1. TRANSMITTER PERFORMANCE TESTS – EXHIBIT I
This section documents the test procedures used, and records the results of tests to demonstrate compliance with the
applicable requirements of parts 2 and 87 of the FC Rules and Regulations.
1.1 RF POWER OUTPUT

1.1.1 REQUIREMENTS
FCC Sec. 2.1046
Measurements required: RF power output.
(a) For transmitters other than single sideband, independent sideband and controlled carrier radiotelephone, power
output shall be measured at the RF output terminals when the transmitter is adjusted in accordance with the tune-up
procedure to give the values of current and voltage on the circuit elements specified in Sec. 2.1033(c)(8). The
electrical characteristics of the radio frequency load attached to the output terminals when this test is made shall be
stated.
FCC 87.131
Power must be determined by direct measurement. The following lists authorized emissions and maximum power.
Class of Station Frequency Band Emissions Power
Aircraft (Communications) VHF A3E, A9W 55 w

The power is measured at the transmitter output terminals and the type of power is determined according
to the emission designator as follows:
Mean power (pY) for amplitude modulated emissions and transmitting both sidebands using unmodulated
full carrier.
Power is restricted to the minimum necessary to achieve the required service.

1.1.2 TEST PROCEDURE
The VHF-4000 was adjusted in accordance with the tune-up instructions. Primary power supply was set to 27.5
VDC. Unmodulated carrier power was measured at carrier frequency intervals beginning at 118.000 MHz.
The RF load for these measurements was a 30 dB attenuator with an HP435B Power Meter. The characteristics of
the attenuator and Power Meter were measured with an HP8753C network analyzer and 856046A S-Parameter test
set. A table of VSWR values taken vs. frequency from 118 to 137 MHz follows the power data, and shows that the
load is essentially 50 ohms resistive over this frequency range.

1.1.3 TEST RESULTS
The first data sheet that follows is the VHF-4000 in AM mode and shows power measurements across the band
covered by this transmitter. The power level is the same for 25 kHz channels as it is for 8.33 kHz channels. Part 87
of the FCC Rules does not define a maximum authorized power. The measured power output is typical of that
provided in VHF transceivers for commercial aircraft.

The second data sheet which follows is the VHF-4000 in digital data VDL Mode 2 and shows power measurements
across the band covered by this transmitter. The measured power output is typical of that provided in VHF
transceivers for commercial aircraft for VDL Mode 2 operations.

1.1.4 POWER OUTPUT DATA SHEET
Type Number: VHF-4000 Serial Number: FBLF
Date Tested: 09/14/01 Tested by: Jerry Chetwynd
TX Power Output
Frequency
20 Watts
118.000 MHz
18 Watts
122.000 MHz
18 Watts
125.000 MHz
18 Watts
129.000 MHz
18 Watts
131.000 MHz
17.5 Watts
133.000 MHz
17.5 Watts
136.975 MHz

Type Number: VHF-4000 VDL MODE 2 Serial Number: FBLF
Date Tested: 9/25/01 Tested by: Bob Lombardi
TX Power Output
Frequency (MHz)
20.32 Watts
118.000
20.18 Watts
122.000
21.09 Watts
125.000
20.70 Watts
129.000
22.70 Watts
131.000
22.34 Watts
133.000
24.77 Watts
136.975

1.1.5 RF LOAD CHARACTERISTICS
Frequency (MHz) RF Load VSWR
118.000 1.03:1
122.000 1.03:1
125.000 1.03:1
129.000 1.03:1
131.000 1.03:1
133.000 1.03:1
137.000 1.03:1

1.2 MODULATION CHARACTERISTICS

1.2.1 REQUIREMENTS
FCC Sec. 2.1047
Measurements required: Modulation characteristics.
(a) Voice modulated communication equipment. A curve or equivalent data showing the frequency response of
the audio modulating circuit over a range of 100 to 5000 Hz shall be submitted. For equipment required to have an
audio low-pass filter, a curve showing the frequency response of the filter, or of all circuitry installed between the
modulation limiter and the modulated stage shall be submitted.
(b) Equipment which employs modulation limiting. A curve or family of curves showing the percentage of
modulation versus the modulation input voltage shall be supplied. The information submitted shall be sufficient to
show modulation limiting capability throughout the range of modulating frequencies and input modulating signal
levels employed.
FCC Sec. 87.141
Modulation requirements.
(a) When A3E emission is used, the modulation percentage must not exceed 100 percent. This requirement does
not apply to emergency locator transmitters or survival craft transmitters.
(b) A double sideband full carrier amplitude modulated radiotelephone transmitter with rated carrier power output
exceeding 10 watts must be capable of automatically preventing modulation in excess of 100 percent.

1.2.2 TEST PROCEDURE
Frequency Response Data
The audio generator is set to 1000 Hz, and its level adjusted to 0.25 Vrms. The transmitter modulation was adjusted
to produce 90% modulation on the 25 kHz channels and on the 8.33 kHz channels. While maintaining this input
level, the modulation depth is recorded over the frequency range of 100 Hz to 5000 Hz.
Compression Characteristic Data
Next, with audio generator set to 1000 Hz, the modulation depth was recorded for audio generator output levels over
the range of 10 mVrms to 1.0 Vrms. This procedure was repeated at modulating frequencies of 100 Hz, 350 Hz,
2500 Hz, and 5000 Hz.

1.2.3 TEST RESULTS
The data following represents the results of these measurements of modulation frequency response and compressor
limiting characteristics on the VHF-4000.

Type Number: VHF-4000 Serial Number: FBLF
Date Tested: Tested by: Jerry Chetwynd
Frequency Response Data
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Frequency Modulation Relative Modulation Relative
(Hz) Depth (%) Response (dB) Depth (%) Response (dB)
100 10.2 -18.91 10.7 -19.3
350 74.0 -1.70 73 -1.7
600 88.0 -0.20 82.2 -0.6
1000 90.0 0.00 90.0 0
1500 90.2 0.02 85 -0.3
2000 88.5 -0.15 84 -0.5
2500 82.0 -0.81 77.5 -1.2
3000 63.0 -3.10 7.0 -22
4000 21.2 -12.56 .5 -52
5000 7.3 -21.82 .5 -52

Compression Characteristic Data
Frequency: 100 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 1.0 1.0
20 1.1 1.2
30 1.2 1.6
40 1.3 2.0
60 1.5 2.7
80 1.7 3.5
100 2.1 4.3
150 2.7 6.7
300 4.9 10.6
600 9.0 10.6
1000 10.0 10.6

Frequency: 350 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 4.5 6.1
20 8.5 11.7
30 11.8 17.5
40 16.0 23.0
60 24.0 34.6
100 39.1 56.5
150 57.9 72.8
300 74.2 72.9
600 74.2 73.2
1000 74.2 73.4

Frequency: 600 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 4.6 6.3
20 9.8 12.5
30 14.5 18.2
40 18.5 23.9
60 28.0 35.9
80 37.0 47.2
100 47.0 58.7
150 68.3 81.0
300 88.1 82.3
600 89.0 83.0
1000 88.0 83.0

Frequency: 1000 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 7.3 8.4
20 14.7 15.6
30 20.7 23.5
40 28.0 30.0
60 39.4 46.5
80 52.5 63.0
100 64.6 79.0
150 90.5 88.6
300 90.4 88.8
600 90.2 89.0
1000 90.4 89.0

Frequency: 2000 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 14.4 8.6
20 27.0 16.0
30 40.7 24.1
40 51.4 32.1
60 76.3 48.0
80 88.2 64.0
100 88.4 80.0
150 88.4 83.7
300 88.7 83.8
600 88.1 83.8
1000 88.3 83.8

Frequency: 3000 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 5.7 1.2
20 10.0 1.7
30 14.0 2.3
40 18.7 2.8
60 27.2 4.0
80 35.3 5.0
100 43.9 6.2
150 62.8 7.0
300 63.0 7.0
600 63.0 6.9
1000 63.0 6.9

Frequency: 4000 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 2.5 0.7
20 4.0 0.9
30 5.8 0.9
40 7.0 0.7
60 10.0 0.7
80 13.0 0.7
100 16.0 0.7
150 21.4 0.7
300 22.2 0.4
600 22.2 0.4
1000 21.7 0.4

Frequency: 5000 Hz
25 kHz Channel, 126.500 MHz 8.33 kHz Channel, 126.500 MHz
Input Modulation Modulation
Level (mVrms) Depth (%) Depth (%)

10 1.8 0.7
20 2.4 0.7
30 3.0 0.7
40 3.8 0.7
60 5.2 0.7
80 6.5 0.7
100 7.4 0.7
150 9.3 0.4
300 8.2 0.4
600 8.0 0.4
1000 7.8 0.4

1.3 OCCUPIED BANDWIDTH

1.3.1 REQUIREMENTS
FCC Sec. 2.1049
Measurements required: Occupied bandwidth.
The occupied bandwidth, that is the frequency bandwidth such that, below its lower and above its upper frequency
limits, the mean powers radiated are each equal to 0.5 percent of the total mean power radiated by a given emission
shall be measured under the following conditions as applicable:
(c) Radiotelephone transmitters equipped with a device to limit modulation or peak envelope power shall be
modulated as follows. For single sideband and independent sideband transmitters, the input level of the modulating
signal shall be 10 dB greater than that necessary to produce rated peak envelope power.
(1) Other than single sideband or independent sideband transmitters--when modulated by a 2500 Hz tone at an
input level 16 dB greater than that necessary to produce 50 percent modulation. The input level shall be established
at the frequency of maximum response of the audio modulating circuit.
FCC Sec. 87.135
Bandwidth of emission.
(a) Occupied bandwidth is the width of a frequency band such that, below the lower and above the upper
frequency limits, the mean powers emitted are each equal to 0.5 percent of the total mean power of a given emission.
(b) The authorized bandwidth is the maximum occupied bandwidth authorized to be used by a station.
(c) The necessary bandwidth for a given class of emission is the width of the frequency band which is just
sufficient to ensure the transmission of information at the rate and with the quality required under specified
conditions.
FCC 87.137
In the band, 117.975-136 MHz, the authorized bandwidth is 25 kHz for all transmitter type accepted after 1 January
1974.

1.3.2 TESTS FOR TYPE 5K00A3E EMISSIONS
The VHF-4000 is capable of 5K00A3E emissions on 25 kHz and 8.33 kHz spaced channels. The following tests
demonstrate the occupied bandwidth for 25 kHz and 8.33 kHz channels is less than 25 kHz. The following test
demonstrates the occupied bandwidth for 8.33 kHz channel operation is less than 8.33 kHz. It also demonstrates
that operation on 8.33 kHz channels will have an occupied bandwidth of less than or equal to 5.0 kHz.
1.3.2.1 TEST PROCEDURE
With the radio tuned to 126.5 MHz (25 kHz channel) and at the frequency of maximum response, the audio input
level required to produce 50% modulation was determined by temporarily substituting a modulation analyzer for the
spectrum analyzer (see test set-up below). The modulating frequency was then set to 2500 Hz, and the input level
was 16 dB above that level determined above.
The transmitted spectrum was then displayed with resolution sufficient to resolve adjacent sidebands. The spectral
data were recorded and converted to relative power levels. These data were then analyzed to determine the occupied
bandwidth such that no more than 0.5 percent of the total radiated power occupied the spectrum above or below this
band.
The test was repeated on 126.505 (8.33 kHz channel on 126.500 MHz) using modulating tones of 2500 Hz.

Audio Generator VHF-4000
Test Panel

Audio Voltmeter
VHF-4000 Spectrum
30 dB Pad
UUT Analyzer

Modulation
Analyzer

1.3.2.2 TEST RESULTS
The occupied bandwidth is 5 kHz. The plots shown below show the radiated spectrum. The data that follows also
shows the measurements and calculations.

Occupied Bandwidth Data Sheet

Type Number: VHF-4000 Serial Number: FBLF

Date tested: 09/17/01 Tested by: Jerry Chetwynd

25 kHz channel & 2.5 kHz Mod tone

Carrier Power = 18 watts Frequency 126.500 MHz
Frequency Relative Level Absolute % Power
(MHz) (dBc) Power (Watts)

126.5125 -64.7 6.0256E-06 2.41254E-05
126.5100 -60.0 1.7783E-05 7.11991E-05
126.5075 -43.5 0.00079433 0.003180349
126.5050 -26.7 0.03801894 0.15222107
126.5025 -6.99 3.55631319 14.23884526
126.5000 0 17.7827941 71.19914369
126.4975 -6.97 3.57272838 14.30456879
126.4950 -28.5 0.02511886 0.100571464
126.4925 -47.4 0.00032359 0.001295611
126.4900 -62.9 9.1201E-06 3.65153E-05
126.4875 -62.3 1.0471E-05 4.19252E-05

Total Power = 24.976 watts 0.5% of total power = 0.1249 watts

Power over +/- 2.5 kHz = 24.912 watts

Percent of total power over +/- 2.5 kHz = 99.744%

Percent of total power outside +/- 2.5 kHz = 0.256 %

Occupied Bandwidth Data Sheet

Type Number: VHF-4000 Serial Number: FBLF

Date tested: 09/17/01 Tested by: Jerry Chetwynd

8.33 kHz channel & 2.5 kHz Mod tone

Carrier Power = 18 watts Frequency 126.500 MHz
Frequency Relative Level Absolute % Power
(MHz) (dBc) Power (Watts) outside ±2.5KHz

126.5125 -63.3 8.3176E-06 3.33023E-05
126.5100 -56.4 4.0738E-05 0.000163108
126.5075 -43.4 0.00081283 0.003254429
126.5050 -26.7 0.03801894 0.15222107
126.5025 -7.0 3.54813389 14.20609683
126.5000 0 17.7827941 71.19914369
126.4975 -6.95 3.58921935 14.37059568
126.4950 -28.7 0.02398833 0.096045002
126.4925 -46.2 0.00042658 0.001707948
126.4900 -59.6 1.9498E-05 7.80683E-05
126.4875 -61.5 1.2589E-05 5.04051E-05

Total Power = 24.983 watts 0.5% of total power = 0.1249 watts

Power over +/- 2.5 kHz = 24.920 watts

Percent of total power over +/- 2.5 kHz = 99.747%

Percent of total power outside +/- 2.5 kHz = 0.252%

1.4 SPURIOUS EMISSIONS AT ANTENNA TERMINAL

1.4.1 REQUIREMENTS
FCC Sec. 2.1051
Measurements required: Spurious emissions at antenna terminals.
The radio frequency voltage or powers generated within the equipment and appearing on a spurious frequency shall
be checked at the equipment output terminals when properly loaded with a suitable artificial antenna. Curves or
equivalent data shall show the magnitude of each harmonic and other spurious emission that can be detected when
the equipment is operated under the conditions specified in Sec. 2.1049 as appropriate. The magnitude of spurious
emissions which are attenuated more than 20 dB below the permissible value need not be specified.
FCC Sec. 2.1057

Frequency spectrum to be investigated.

(a) In all of the measurements set forth in Secs. 2.1051 and 2.1053, the spectrum shall be investigated
from the lowest radio frequency signal generated in the equipment, without going below 9 kHz, up to at
least the frequency shown below:

(1) If the equipment operates below 10 GHz: to the tenth harmonic of the highest fundamental
frequency or to 40 GHz, whichever is lower.

(b) Particular attention should be paid to harmonics and subharmonics of the carrier frequency as well as
to those frequencies removed from the carrier by multiples of the oscillator frequency. Radiation at the
frequencies of multiplier stages should also be checked.

(c) The amplitude of spurious emissions which are attenuated more than 20 dB below the permissible
value need not be reported.
FCC 87.139 (a)
The mean power of any emissions shall be attenuated below the mean output power of the transmitter (pY) as
follows:
(1) When the frequency is removed from the assigned frequency by more than 50 percent up to and including 100
percent of the authorized bandwidth the attenuation shall be at least 25 dB.
(2) When the frequency is removed from the assigned frequency by more than 100 percent up to and including 250
percent of the authorized bandwidth the attenuation shall be at least 35 dB.
(3) On any frequency removed from the assigned frequency by more than 250 percent of the authorized bandwidth
the attenuation for aircraft station transmitters shall be at least 40 dB; and the attenuation of aeronautical station
transmitters must be at least 43 +10 * log10(pY) dB.

1.4.2 TEST PROCEDURE
At the frequency of maximum response, the audio input level required to produce 50% modulation was determined
by temporarily substituting a modulation analyzer for the spectrum analyzer (see test set-up for modulation
characteristics measurements). The modulating frequency was then set to 2500 Hz, and the input level was set 16
dB above that level determined above. The transmitted spectrum was then examined with resolution sufficient to
verify that no spurious output exceeded the allowable level. The spectrum was examined to beyond the tenth
harmonic.
1.4.3 TEST RESULTS
No spurious output exceeded the allowable level. The following data sheets show the results of the measurements.

Spurious Emissions Data Sheet

Type Number: VHF-4000 Serial Number: FBLF

Date tested: 09/19/01 Tested by: Jerry Chetwynd

Measurement at 118.000 MHz Carrier Power = 20 watts

Maximum allowable power for any spurious emission: -60 dBc
Spurious DB
Emission Relation to Below
Frequency Carrier Carrier
nd
236.0 MHz 2 harmonic 117.8
rd
354.0 MHz 3 harmonic 119.4
th
472.0 MHz 4 harmonic >120.0
th
590.0 MHz 5 harmonic 114.4
th
708.0 MHz 6 harmonic >120.0
th
826.0 MHz 7 harmonic >120.0
th
944.0 MHz 8 harmonic >120.0
th
1062.0 MHz 9 harmonic >120.0
th
1180.0 MHz 10 harmonic >120.0
th
1298.0 MHz 11 harmonic >120.0
th
1416.0 MHz 12 harmonic >120.0
th
1534.0 MHz 13 harmonic >120.0
th
1652.0 MHz 14 harmonic >120.0
No further harmonics measured
115.5 MHz Non-harmonic spurious 95
138.6 MHz Non-harmonic spurious 115
No other non – harmonic spurious emissions were noted

Spurious Emissions Data Sheet

Type Number: VHF-4000 Serial Number: FBLF

Date tested: 09/19/01 Tested by: Jerry Chetwynd

Measurement at 127.000 MHz Carrier Power = 18 watts

Maximum allowable power for any spurious emission: -60 dBc
Spurious DB
Emission Relation to Below
Frequency Carrier Carrier
nd
254.0 MHz 2 harmonic 117.6
rd
381.0 MHz 3 harmonic 99.0
th
508.0 MHz 4 harmonic >120.0
th
635.0 MHz 5 harmonic 113.9
th
762.0 MHz 6 harmonic >120.0
th
889.0 MHz 7 harmonic >120.0
th
1016.0 MHz 8 harmonic >120.0
th
1143.0 MHz 9 harmonic >120.0
th
1270.0 MHz 10 harmonic >120.0
th
1397.0 MHz 11 harmonic >120.0
th
1524.0 MHz 12 harmonic >120.0
th
1651.0 MHz 13 harmonic >120.0
No further harmonics measured
115.5 MHz Non-harmonic spurious 105
138.6 MHz Non-harmonic spurious 110
No non-harmonic spurious emission were noted.

Spurious Emissions Data Sheet

Type Number: VHF-4000 Serial Number: FBLF

Date tested: 09/19/01 Tested by: Jerry Chetwynd

Measurement at 136.975 MHz Carrier Power = 18 watts

Maximum allowable power for any spurious emission: -60 dBc
Spurious DB
Emission Relation to Below
Frequency Carrier Carrier
nd
273.95 MHz 2 harmonic 117.4
rd
410.925 MHz 3 harmonic 95.5
th
547.9 MHz 4 harmonic >120.0
th
684.875 MHz 5 harmonic 113.7
th
821.85 MHz 6 harmonic >120.0
th
958.825 MHz 7 harmonic >120.0
th
1095.8 MHz 8 harmonic >120.0
th
1232.775 MHz 9 harmonic >120.0
th
1369.750 MHz 10 harmonic >120.0
th
1506.725 MHz 11 harmonic >120.0
th
1643.700 MHz 12 harmonic >120.0
th
1780.675 MHz 13 harmonic >120.0
No further harmonics measured
138.6 MHz Non-harmonic spurious 105

No non-harmonic spurious emission were noted.

1.5 FIELD STRENGTH OF SPURIOUS RADIATION

1.5.1 REQUIREMENTS
FCC Sec. 2.1053
Measurements required: Field strength of spurious radiation.
(a) Measurements shall be made to detect spurious emissions that may be radiated directly from the cabinet,
control circuits, power leads, or intermediate circuit elements under normal conditions of installation and operation.
Curves or equivalent data shall be supplied showing the magnitude of each harmonic and other spurious emission.
For equipment operating on frequencies below 890 MHz, an open field test is normally required, with the measuring
instrument antenna located in the far-field at all test frequencies. Information submitted shall include the relative
radiated power of each spurious emission with reference to the rated power output of the transmitter, assuming all
emissions are radiated from half-wave dipole antennas.
(b) The measurements specified in paragraph (a) of this section shall be made for the following equipment:
(1) Those in which the spurious emissions are required to be 60 dB or more below the mean power of the
transmitter.
(2) (2) All equipment operating on frequencies higher than 25 MHz.

FCC Sec. 2.1057

Frequency spectrum to be investigated.

(a) In all of the measurements set forth in Secs. 2.1051 and 2.1053, the spectrum shall be investigated
from the lowest radio frequency signal generated in the equipment, without going below 9 kHz, up to at
least the frequency shown below:

(1) If the equipment operates below 10 GHz: to the tenth harmonic of the highest fundamental
frequency or to 40 GHz, whichever is lower.

(b) Particular attention should be paid to harmonics and subharmonics of the carrier frequency as well as
to those frequencies removed from the carrier by multiples of the oscillator frequency. Radiation at the
frequencies of multiplier stages should also be checked.

(c) The amplitude of spurious emissions which are attenuated more than 20 dB below the permissible
value need not be reported.

FCC 87.139 (a)
The mean power of any emissions shall be attenuated below the mean output power of the transmitter (pY) as
follows:
(1) When the frequency is removed from the assigned frequency by more than 50 percent up to and including 100
percent of the authorized bandwidth the attenuation shall be at least 25 dB.
(2) When the frequency is removed from the assigned frequency by more than 100 percent up to and including 250
percent of the authorized bandwidth the attenuation shall be at least 35 dB.
(3) On any frequency removed from the assigned frequency by more than 250 percent of the authorized bandwidth
the attenuation for aircraft station transmitters shall be at least 40 dB; and the attenuation for aeronautical
station transmitters must be at least 43 + 10 * log10(pY) dB.

1.5.2 TEST PROCEDURE
This test was performed on an open-field range meeting the requirements of ANSI Standard c63.4-1992. Testing
was performed in Rubicom Systems, Inc., 284 West Drive, Melbourne FL. Rockwell Collins supplied the VHF-
4000 unit to be tested, mounting tray, cables, interface unit and power supply. Rubicom supplied radiated
measuring equipment (calibrated antennae and spectrum analyzer) and measurement platform.
1.5.3 TEST RESULTS
The test report indicates the requirements were met. The test report from Rubicom Systems, Inc. is in Exhibit K.

1.6 FREQUENCY STABILITY

1.6.1 REQUIREMENTS

FCC Sec. 2.1055 (a)

Measurements required: Frequency stability.

(a) The frequency stability shall be measured with variation of ambient temperature as follows:

(2) From -20 deg. to +50 deg. centigrade for equipment to be licensed for use in the Maritime Services
under part 80 of this chapter, except for Class A, B, and S Emergency Position Indicating Radiobeacons
(EPIRBS), and equipment to be licensed for use above 952 MHz at operational fixed stations in all
services, stations in the Local Television Transmission Service and Point-to-Point Microwave Radio
Service under part 21 of this chapter, and equipment licensed for use aboard aircraft in the Aviation
Services under part 87 of this chapter.

FCC 2.1055 (b)

Frequency measurements shall be made at the extremes of the specified temperature range and at
intervals of not more than 10 deg. centigrade through the range. A period of time sufficient to stabilize all
of the components of the oscillator circuit at each temperature level shall be allowed prior to frequency
measurement. The short term transient effects on the frequency of the transmitter due to keying (except
for broadcast transmitters) and any heating element cycling normally occurring at each ambient
temperature level also shall be shown. Only the portion or portions of the transmitter containing the
frequency determining and stabilizing circuitry need be subjected to the temperature variation test.

FCC 2.1055 (d)

The frequency stability shall be measured with variation of primary supply voltage as follows:

(1) Vary primary supply voltage from 85 to 115 percent of the nominal value for other than hand carried
battery equipment.

(2) The supply voltage shall be measured at the input to the cable normally provided with the equipment,
or at the power supply terminals if cables are not normally provided. Effects on frequency of
transmitter keying at the nominal supply voltage and at each extreme also shall be shown.

FCC 87.133 (a)

The carrier frequency of each station in the Aviation Services shall be maintained with the following
percentage of the assigned frequency:

Band – 100 to 137 MHz

Aircraft stations – 30 ppm (+/- 4109 Hz at test frequency of 136.975 MHz)

1.6.2 TEST PROCEDURE
Frequency Stability with Te mperature
The transceiver was tuned to 136.975 MHz. Due to the nature of the frequency synthesizer design, any frequency
error will be the highest at this operating frequency. Chamber air temperature was adjusted to –20 degrees C, and
maintained for at least thirty minutes to allow circuit element stabilization before data were taken. The transmitter
was then keyed, and the steady state frequency was recorded.
To observe the keying transient, the transmitter output signal was mixed with the output of a signal generator. The
signal generator frequency was adjusted to produce a low audio-frequency beat note against the transmitter steady-
state frequency. The beat frequency was observed on an oscilloscope, triggered when the transmitter was keyed.
This procedure was repeated at 10 degrees C intervals to +50 degrees c. Steady state frequency measurements were
taken every 10 degrees C. Keying transient measurements were taken at the temperature extremes and at 25 degrees
C.
Frequency Stability with Supply Voltage
This transceiver is intended for operation in 27.5 VDC electrical systems. Steady-state and transient frequency
measurements were made at nominal supply voltage, and at 85% and 115% of nominal voltage. The transceiver was
tuned to a frequency of 136.975 MHz. These measurements were made at nominal room temperature.

1.6.3 TEST RESULTS
The requirements were met. The data sheets show steady-state frequency at each temperature and line voltage. The
oscilloscope photographs show the beat frequency as a function of time, after keying the transmitter, between the
transmit frequency and a stable reference oscillator offset 1 kHz from 136.975000 MHz. No keying transients were
observable.

Frequency Stability Data Sheet
Type Number: VHF-4000 Serial Number: FBLF
Data Tested 09/17/01 Tested by: Jerry Chetwynd
Frequency Stability with Te mperature
Temperature Measured Frequency
Frequency (MHz) Error
-20 ° C 136.975040 40HZ
-10 ° C 136.975030 30HZ
-0 ° C 136.975080 80HZ
+10 ° C 136.975100 100HZ
+20 ° C 136.975050 50HZ
+30 ° C 136.975040 40HZ
+40 ° C 136.975040 40HZ
+50 ° C 136.975120 120HZ
Maximum Allowable Frequency Error = 4109 Hz

Frequency Stability with Supply Voltage
Supply Measured Frequency
Voltage Frequency Error (Hz)
23.38 VDC (85%) 136.975050 50HZ

27.50 VDU 136.975050 50HZ

31.63 VDC 136.975050 50HZ
(115%)

Maximum Allowable Frequency Error – 4109 Hz

Document Created: 2001-10-25 11:54:45
Document Modified: 2001-10-25 11:54:45

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