PD4PB01TRemote Control Security Transmitter

ENGINEERING STATEMENT IN REGARD TO MEASUREMENTS ON Lentek International FCC ID: PD4PB01T A. INTRODUCTION Hyak Laboratories Inc. has been authorized by Lentek International, to perform measurements on a transmitter to determine compliance with FCC Rules, Subpart C. The device is a low powered, battery operated transmitter designed as a pet security system. It operates at a nominal 315 MHz frequency. The transmitter, constructed on an etched circuit card, is powered from a 3 volt lithium battery. An integral, etched- circuit antenna is used. The device meets the provisions of Para. 15.231(e) since as an automatically operated device it transmits for only a nominal 300 milliseconds with a silent period between transmissions of over 30 times the duration and at least 10 seconds. B. REPORT OF PERIODIC OPERATION Figure 1 is a time-domain plot of transmission duration. Nominal duration is 280 milliseconds. Figure 2 is a time-domain plot showing silent period between Automatic transmission of 10 seconds. C. DESCRIPTION OF MEASUREMENT FACILITIES A description of the Hyak Laboratories Inc. radiation test facility is a matter of record with the FCC. The facility was accepted for radiation measurements on October 1, 1976, and is currently listed as an acceptable site. D. DESCRIPTION OF MEASUREMENT PROCEDURE: RADIATED MEASUREMENTS Measurements of transmitter radiation field strength were made using ANSI C63.4 (1992) as the test procedure. Measurements were made with 3 meter spacing between the transmitter under test and the test equipment antenna. The transmitter under test was placed on a rotatable table approximately 80 cm in height. The power supply was a fresh battery. 2 FIGURE 1 TRANSMISSION DURATION Horizontal: 100 mS/Div Vertical: 10 dB/Div Resolution: 1 MHz (Time Domain) Transmission Timing FCC ID: PD4PB01T Figure 1 3 FIGURE 2 TRANSMISSION DURATION LIMITING Horizontal: 5 seconds/Div Vertical: 10 dB/Div Resolution: 1 MHz (Time Domain) Transmission Timing FCC ID: PD4PB01T Figure 2 4 D. DESCRIPTION OF MEASUREMENT PROCEDURE: RADIATED MEASUREMENTS (Continued) Measurement of field strength was made through use of HP 8596E and Tektronix 494P spectrum analyzers in conjunction with a HP 8447D and Avantek wide band, low noise preamplifiers; and an Advantest R3361A spectrum analyzer with quasi-peak detector. Singer DM-105A series calibrated dipoles were used as the test antennas in the 25-1000 MHz range. An EMCO 3115 calibrated horn antenna was used between 1 and 4.4 GHz. An analysis of time domain measurements (see plots in Figures 3 and 4) was made to determine average field intensity of the fundamental and any harmonics outside of forbidden bands. Sample calculations are included in Figure 5. Based on time domain observations, and using the procedures of Figure 4, a correction factor for a nominal 100 mS averaging interval was computed. Data for radiated emissions in Table 1 includes this correc- tion factor. For emissions that fell in forbidden bands below 1 GHz the CISPR quasi-peak detector was used. For each spurious emission identified between 30 MHz to the tenth harmonic the test assembly was rotated for maximum pickup, the test antenna varied in elevation and the test antenna polari- zation shifted between horizontal to vertical in order to maximize observed signals. The measurement procedure included recording the worst-case field strength for receiving antenna polarization, test antenna height variation from 3 feet to 10 feet, test sample rotation, and placing the test sample on each of its major planes. The spectrum was checked from 30 MHz to the tenth harmonic. All emissions not reported were more than 20 dB below the permitted level or below FCC limits but in the ambient/system noise floor. Tabulation of the measurements are shown in Table 1. Specific forbidden band scans were made per Paragraph 15.205 and 15.209. E. REPORT OF RADIATED MEASUREMENTS Table 1 lists the frequency and amplitude of all signals observed from 30 MHz to the tenth harmonic that were within 20 dB of the limits of FCC Rules. The averaging factor is included as noted. 5 FIGURE 3 COMPLETE WORD TRANSMISSION Horizontal: 10 milliseconds/Div Vertical: 10 dB/Div. Resolution: 1 MHz (Time domain) PULSE CHARACTERISTICS FCC ID: PD4PB01T FIGURE 3 6 FIGURE 4 WORD DETAIL Horizontal: 2 milliseconds/Div Vertical: 10 dB/Div. Resolution: 1 MHz (Time domain) PULSE CHARACTERISTICS FCC ID: PD4PB01T FIGURE 4 7 SAMPLE COMPUTATIONS Using the time domain plots of Figures 3 and 4, maximum "on" time over any 100 mS interval is: Pulses: “On” 58x0.8 = 46.4 Duty Cycle: 46.4/100 = 0.46 20 Log 0.46 = -6.7 dB SAMPLE COMPUTATIONS FCC ID: PD4PB01T FIGURE 5 8 TABLE 1 RADIATED FIELD INTENSITY Measured at 3 meters 15.231(b) Meter 1 Antenna Field 2 Calc. Field 3 Frequency Reading Factor Intensity Intensity FCC Limit dB to (MHz) (dBm) (dB) uV/m @ 3m uV/m @ 3m uV/m @ 3m Limit 315.45 -60.4 21.8 2630.3 1216.2 2417.7 - 6.0 630.91 -83.2 28.5 412.1 190.5 241.8 - 2.1 946.32 -86.3 32.6 462.4 213.8 241.8 - 1.1 1261.30 -86.8 25.1 184.1 85.1 241.8 - 9.1 1578.00 -94.8 26.1 82.2 38.0 241.8 -16.1 1894.60 -89.6 27.8 182.0 84.1 241.8 - 9.2 2209.20 -92.4 28.8 147.9 68.4 241.8 -11.0 2524.80 -94.8 29.7 124.5 57.5 241.8 -12.5 2840.40 -91.2 30.4 204.2 94.4 241.8 - 8.2 3156.00 -95.2 31.3 142.9 66.1 241.8 -11.3 Note 1: Peak detector reading without averaging. Note 2: uV/m = Log - 1dBu/m 20 dBu = dBm + antenna factor + 107 Note 3: Field Intensity calculated from peak value and -6.7 dB peak/average factor. *Forbidden Band All other emissions to the tenth harmonic were below FCC limits. (Unit was measured on 3 major planes) RBW: 100 kHz to 1 GHz; 1 MHz if > 1GHz (Measured at 1 m extrapo- lated to 3 m). No video filtering. Peak responding, rms calibrated detector. RADIATED FIELD INTENSITY FCC ID: PD4PB01T TABLE 1 9 D. FORBIDDEN BAND MEASUREMENTS Any spurious signals from the transmitter that fell in a forbidden band are identified in Table 1. All forbidden bands, per Paragraph 15.205…

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