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FCC ID: JTE-GMT20

Test Report

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FCCID_853

FCC ID: JTE—GMT20 A. INTRODUCTION The following data are submitted in connection with this request for Type Acceptance of the GMT—20 transmitter in accord— ance with Part 2, Subpart J of the FCC Rules. The GMT—20 is a 20 watt transmitter that can generate both CW and GSM modulated test signals in the broadband PCS bands. It is used to establish signal propagation modeling from potential base station sites and refine calculated coverage predictions. B. GENERAL INFORMATION REQUIRED FOR TYPE ACCEPTANCE (Paragraph 2.983 of the Rules) 1. Name of applicant: Grayson Electronics Co. 2. Identification of equipment: a. The equipment identification label is shown in Appendix 1. b. Photographs of the equipment are included in Appendix 2. 3. Quantity production is planned. 4. Technical description: a. NON, 300kGXD emission. b. Frequency range: 1.85 — 1.99 GHz. c. Operating power of transmitter is fixed at the factory at 20 watts and can be reduced to 2 milli— watts. a. The GMT~20 fully complies with applicable power limits under Part 24. e. The dc voltage and dc currents at each final amplifier: Collector voltage: 12.0 vae Collector current: 3.6 A f. Function of each active semiconductor device: See Appendix 3. g. Complete circuit diagram is included in Appendix 4. h. A draft instruction book is submitted as Appendix 5. i. The transmitter tune—up procedure is included in Appendix 6. j. A description of circuits for stabilizing frequen— cy is included in Appendix 7.

FCC ID: JTE—GMT2O0 B. GENERAL INFORMATION REQUIRED FOR TYPE ACCEPTANCE (cont‘d) k. A description of circuits and devices employed for suppression of spurious radiation in Appendix 8. 1. Not applicable. 5. Data for 2.985 through 2.997 follow this section. c. RF POWER OUTPUT (Paragraph 2.985(a) of the Rules) RF power output was measured with a HP 432A/HP478A RF power meter and a Narda 765—20 attenuator as a 50 ohm dummy load. Maximum power measured was 20 watts; minimum power was 2 milli— watts. (The transmitter was tuned by the factory according to the procedure of Exhibit 4.) D. MODULATION CHARACTERISTICS The GMT—20 transmitter modulation linearity was tested under GSM formats. GSM signal source was an Tektronix model 2021 Arbitrary Waveform Generator (AWG) Modulation consisted of a pseudo—random bit stream at 270.833 kB/s that had a length of 2047 bits, using 800 samples with a sample rate of 2.167 MHz. Symbol rate was > 50 kHz. Based on Para. 24.238, measured emission bandwidth at 26 dB points was 300 kHz.

FPCC ID: JTE—GMT20 4 \emavon . omm FIGURE 1 REF LEVEL FAEGUENCY FREG _SPAN/ODI 30 . 0dBnm 1900. 00 OMHz 50kH27 oOd ~—eF] . on io 7 _# + s pe + —ao C = ho omm iA M en 3 pplrerP i 40106 Lt n 1210104 10104 4. > |i_1_"'H+f_L L_LUL4 $.1.0101 401034 14 $ 100B/ o ef=] 10kHz VERTICAL RF RESOLUTION L___________DISPLAY._____ATTENUATION BANDWIDTH CW Carrier 20W FCC ID: JTE—GMT20 FIGURE 1

PCC ID: JTE—GMT20 s« \emayous. oo FIGURE 2 REF LEVEL FREQUENCY FREQ _SPAN/DIV —10.0dBm 1900 .O000MHz 5OkHz TD— 7 4— ~140 75 x —29| + z0| _ ]F: _ + —= & + [X a a a a uc s ae mc a s 1. i 0B 100B 0dB 10kHz VERTICAL RF RESOLUTION BANOWIDTH CW Carrier 2 mW FCC ID: JTE—GMT20 FIGURE 2

FCC ID: JTE—CGMT20 A Nenave. oms FIGURE 3 REF LEVEL FREGQUENCY FREG SPAN/DIV 100 30 .OdBm 19004+. 00 OMHz 100kHz / HEF] ns —19] 7e ~20 + —# io T —40 + , so + § _'z‘.“ q a a c ul y gaa + h m P& i pllga ul gla bgcracdhrg i 100B/ VERATICAL dB ARF 10kHz RESOLUTION ____________________ GSM, 20 w FCC ID: JTE—GMT20 FIGURE 3

PCC ID: JTE—GMT20 a Nenayee ons FIGURE 4 REF LEVEL FREgUENCY FREG SPAN/DIV —10.0dBm 1900 . 000MHz 100kHz ROVY— TE ~TEF| + _—10; = Lr/(‘vni"::fi1 —= o + w — y _ 'U _E + | V Y > € 70 $ paca hfi a i ue uc aa + faa mAPPF y Li s Euy gaa uces T4 f 10d0B/ 0dB 10kHz VERTICAL AF RESOLUTION RISPLAY_______ATTENUATION ___BANDWIDTH CSM, 2 nw FCC ID: JTR—GMT20 FIGURE 4

PCC ID: JTE—GMT20 E. SPURIOUS EMISSIONS AT THE ANTENNA TERMINALS (Paragraph 2.991 of the Rules) The GMT—20 transmitter was tested for spurious emissions at the antenna terminals while the equipment was modulated with a GSM signal previously described. Measurements were made with Tektronix 494P spectrum analy— zer coupled to the transmitter output terminal through a Narda 765~20 power attenuator and general radio 874—GAL variable atten— uator. A notch filter was used to attenuate the carrier. During the tests, the transmitter was terminated in the 50 ohm attenuator, do supply was 117 volts throughout the tests. Spurious emissions were measured at 2 mW and 20 watts output throughout the RF spectrum from 10 to the tenth harmonic of the carrier. Any emissions that were between the required attenuation and the noise floor of the spectrum analyzer were recorded. Data are shown in Table 1. F. DESCRIPTION OF RADIATED SPURIOUS MEASUREMENT FACILITIES A description of the Hyak Laboratories‘ radiation test facility is a matter of record with the FCC. ‘The facility was accepted for radiation measurements from 25 to 1000 MHz on Octo— ber 1, 1976 and is currently listed as an accepted site.

FCC ID: JTE—GMT20 TABLE 1 TRANSMITTER CONDUCTED SPURIOUS 1.850 MHz, 117 Vac Input, 2 mW and 20 watts Spurious dB Below Frequency Carrier ___MH2 Reference 20W 3700.000 >103* 5550.000 >102* 7400.000 >90* 9250 .000 >90* 11100.000 >88* 12950.000 >86* 14800.000 >86* 16650 .000 >84* 18500.000 >82* Required:l 56 2 mW 3700.000 >100* 5550.000 >97* 7400.000 >82% 9250 .000 >81* 11100.000 >84* 12950 .000 >77* 14800.000 >79% 16650.000 >77* 18500.000 >74* Required:l 16 All other emissions from 10 MHz to the tenth harmonic were 20 dB or more below FCC limit. *Reference data only, more than 20 dB below FCC limit. NOTE: Carrier notch filter used to increase dynamic range. 1 Required dBC = 43+10 LogipP

FCC ID: JTE—GMT20 G. FIELD STRENGTH MEASUREMENTS OF SPURIOUS RADIATION Field intensity measurements of radiated spurious emissions from the GMT—20 were made with a Tektronix 494P spectrum ana— lyzer using Singer DM—105A calibrated dipole antennas below 1 GHz, and EMCO 3115 or 3116 horn antennas over 1 GHz. The transmitter and dummy load were located in an open field 3 meters from the test antenna. Supply voltage was a power supply with a terminal voltage under load of 117 Vac. Output power was 20 watts at the 1850.00 MHz operating fre— quency. The transmitter and test antennas were arranged to maximize pickup. Both vertical and horizontal test antennae polarization were employed. Reference level for the spurious radiations was taken as an ideal dipole excited by 20 watts, the output power of the trans— mitter according to the following relationship:* Eo = (49.294)‘"2 R where Eo= electric—field intensity in volts/meter Pp = transmitter power in watts Ro= distance in meters for this case Eo = (49.2320)1/2 = 10.5 V/m 3 Since the spectrum analyzer is calibrated in decibels above one milliwatt (dBm)}, a conversion, for convenience, was made from dBu to dBn. 10.5 volts/meter 10.5x108 uv/m aBu/m 20 Logqip(10.5x10°) 140 dBu/m I Since 1 uV/m —107 dBm, the reference becomes 140 — 107 33 dBnm i *Reference Data for Radio Engineers, Fourth Edition, International Telephone and Telegraph Corp., p. 676. 10

FCC ID: JTE—CGMT20 G. FIELD STRENGTH MEASUREMENTS (Continued) The measurement system was capable of detecting signals 66 dB or more below the reference level. Measurements were made from 10 MHz to 10 times operating frequency. Data after applica— tion of antenna factors and line loss corrections are shown in Table 2. TABLE 2 TRANSMITTER CABINET RADIATED SPURIOUS 1850.000 MHz, 117 Vac, 20 watts Spurious dB Below Frequency Carrier MH2 Reference* 3700.000 75 5550.000 >7 4* * 7400.000 >72** 9250.000 >70* * 11100.000 >67** 12950.000 >66** 14800.000 >65®* 16650 .000 >58** 18500.000 >55% # Required: 43+10Log(P) = 56 iworst—case polarization, H—Horizontal, V—Vertical. * Reference data only, more than 20 dB below FCC limit. **— Measuring system noise floor. Frequencies > 4 GHz measured at 1 m, extrapolated to 3m. All other spurious from 10 MHz to 18.5 GHz were 20 dB or more below FCC limit. 11

FCC ID: JTE—GMT20 H. FREQUENCY STABILITY (Paragraph 2.995(a)(2) and 90.213 of the Rules) Measurement of frequency stability versus temperature was made at temperatures from —30°C to +50°C. At each temperature, the unit was exposed to test chamber ambient a minimum of 60 ni— nutes after indicated chamber temperature ambient had stabilized to within +2° of the desired test temperature. Following the 1 hour soak at each temperature, the unit was turned on, keyed and frequency measured within 2 minutes. Test temperature was sequenced in the order shown in Table 3, starting with —30°cC. A Thermotron S1.2 temperature chamber was used. Temperature was monitored with a Keithley 871 digital thermometer. The transmitter output stage was terminated in a dummy load. Primary supply was 117 Vac. Frequency was measured with a Textronix 494P spectrum analyzer connected to the transmitter through a power attenuator. Measurements were made at 1850.000 MHz. No tran— sient keying effects were observed. TABLE 3 FREQUENCY STABILITY vs. TEMPERATURE 1850.000 MHz; 117 Vac; 20 W Temperature, °C Output Frequency, MHz ppm —30.3 1850.000471 0 .25 —20.6 1850.000458 0 .25 —11.3 1850.000121 0 .07 — 0.1 1849.999874 —0.07 10.6 1849.999964 —0.02 20 .4 1850.000057 —0 .03 30.3 1850.000213 — —0.12 40 .1 1849.999674 —0.18 50.1 1849.999686 —0.17 Maximum frequency error: 1850.000471 1850,000000 + .000471 MHz Rated stability is + 0.5 ppm or a maximum of + .000925 MHz, which corresponds to: High Limit 1850.000925 MHz Low Limit 1849.999075 MHz 12

FCC ID: JTE—GMT20 I. FREQUENCY STABILITY AS A FUNCTION OF SUPPLY VOLTAGE (Paragraph 2.995(d)(2) of the Rules) Oscillator frequency as a function of power supply voltage was measured with a HP 5385A frequency counter as supply voltage provided by an HP 6264B variable dc power supply was varied from +15% above the nominal 117 Vac rating. A Fluke 197 digital voltmeter was used to measure supply voltage at transnmitter primary input terminals. Measurements were made at 20°C ambient. TABLE 4 FREQUENCY STABILITY AS A FUNCTION OF SUPPLY VOLTAGE 1850.000 MHz, 117 Vac Nominal, 20 W & Supply Voltage output Freguency, MHz 115 134.55 1850.000059 110 128.70 1850.000058 105 122.85 1850.000057 100 117.00 1850.000057 95 111.15 1850.000058 90 105.30 1850.000057 85 99 .45 1850.000058 Maximum frequency error: 1850.000059 1850.000000 + .000059 MHz Rated stability is + 0.5 ppm or a maximum of + .000925 MHz, which corresponds to: High Limit 1850.000925 MHz Low Limit 1849.999075 MHz 13


Document Created: 2001-07-17 15:36:49
Document Modified: 2001-07-17 15:36:49
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