Test Data Part 27 Compliance cont

FCC ID: JF6-8702-8W

Test Report

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FCCID_589175

2.983 FIELD OF SPURIOUS RADIATION

The spectrum emissions of the equipment were measured in an anechoic chamber
at a distance of 3 meters. Measurements were made with the receiving antenna
mounted both horizontally and vertically.

Considering the transmitter as a dipole radiator, the field intensity for a given
power at a given distance can be expressed as:

E = 10 log ( ( P x 30 x G)/R2 )

Where: E = field intensity in dBV/m
P = transmitter mean output power (+32 dBm = 2 watts)
G = dipole antenna gain (1.64)
R = radius (3 meters)

E = 10 log ( ( 2 x 30 x 1.64)/9 ) = 10.5 dBv/m = 130.5 dBuV/m

Part 27.53 specifies that emissions below 2300 MHz and above 2370 MHz must
be attenuated from the transmitter power by:

A = 70 + 10 LOG (p) = 70 + 10 LOG (2) = 73 dB

Therefore, the maximum allowable spurious emissions at 3 meters are:

E = 130.5 dBuV/m – 73 dB = 57.5 dBuV/m

Measurements were made using a 1 MHz resolution bandwidth and the levels of
significant (greater than 35 dBuV/m) spurious emissions were recorded.

The significant spurious emissions found are as follows:

Horizontial
Freq Peak AF Gain Corrected Limit (3m) Delta
72.85 52.8 6.9 25 34.7 49.6 14.90
121 45.5 7.9 25 28.4 54 25.60
145.4 51.5 8.5 25 35 54 19.00
148.23 52.1 8.9 25 36 56.9 20.90
169.6 58.1 9.7 25 42.8 56.9 14.10
218.2 56.8 11.3 25 43.1 56.9 13.80
266.9 45.7 12.8 25 33.5 56.9 23.40
274.9 53.4 13.1 25 41.5 56.9 15.40
290.85 46.7 13.6 25 35.3 56.9 21.60
296.4 55.4 14.1 25 44.5 56.9 12.40
315.1 47.2 14.7 25 36.9 56.9 20.00
336.07 50.8 15 25 40.8 56.9 16.10
339.175 54.6 15 25 44.6 56.9 12.30
345.675 60.1 15.4 25 50.5 56.9 6.40
363.875 55.6 15.7 25 46.3 56.9 10.60
395.2 56 16.4 25 47.4 56.9 9.50
411.95 52.8 16.4 25 44.2 56.9 12.70
436.32 48.3 16.4 25 39.7 56.9 17.20
509.12 46.7 18 25 39.7 56.9 17.20
592.33 50.5 19.8 25 45.3 60 14.70
630.7 43.1 21 25 39.1 60 20.90
655 48.9 20.8 25 44.7 60 15.30
825 47.7 22.3 25 45 60 15.00
2036 40.15 21.5 12.5 49.15 60 10.85

No significant spurious emissions were found above 10 GHz.

2.989 FREQUENCY STABILITY

The transmit source that is used is a crystal oscillator operating in the 125 MHz
range and multiplied up to the operating frequency.

Two sources were tested over a temperature range of 0 to + 50 degrees C and the
largest deviation over the specified temperature range was +/- 4 PPM, which is
adequate to maintain the transmit spectrum within the desired band of operation
as per FCC Part 27.54.

Crystal Oscillator Temperature Data

4
3
2
Parts Per Million

1
0
-1
-2
-3
-4
0 5 10 15 20 25 30 35 40 45 50 55
Temperature (Degress C)

The sources were also tested over the range of the DC input voltage and no
significant variation in the frequency was observed.

Document Created: 2005-10-06 13:07:11
Document Modified: 2005-10-06 13:07:11

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