OLTDK-902-T49 MHz Wireless Doorbell TX

TABLE OF CONTENTS LIST APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T TEST REPORT CONTAINING: PAGE 1......TEST PROCEDURE PAGE 2......TEST PROCEDURE CONTD. & CIRCUIT DESCRIPTION PAGE 3-4....RADIATION INTERFERENCE TEST DATA PAGE 5......OCCUPIED BANDWIDTH TEST DATA EXHIBITS CONTAINING: EXHIBIT 1............POWER OF ATTORNEY LETTER EXHIBIT 2............BLOCK DIAGRAM EXHIBIT 3............SCHEMATIC EXHIBIT 4A-4D........PARTS LIST EXHIBIT 5A-5D........INSTRUCTION MANUAL EXHIBIT 6............SAMPLE OF FCC ID LABEL EXHIBIT 7............LOCATION OF FCC ID LABEL EXHIBIT 8............EXTERNAL PHOTO - FRONT SIDE EXHIBIT 9............EXTERNAL PHOTO - BACK SIDE EXHIBIT 10...........INTERNAL PHOTO - COMPONENT SIDE EXHIBIT 11...........INTERNAL PHOTO - COPPER SIDE EXHIBIT 12...........OCCUPIED BANDWIDTH PLOT-PRESS TO TALK EXHIBIT 13...........OCCUPIED BANDWIDTH PLOT-BELL APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T REPORT #: F:\CUS\D\DBL\DLB186A9.RPT PAGE: TABLE OF CONTENTS LIST APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T TEST EQUIPMENT LIST 1. Spectrum Analyzer: Hewlett Packard 8566B - Opt 462, w/ preselector 85685A, & Quasi-Peak Adapter HP 8565OA, & HP 8449B - OPT H02 Cal. 6/26/98 2. Signal Generator, Hewlett Packard 8640B, cal. 10/1/98 3. Signal Generator, HP 8614A Serial No.2015A07428 cal. 5/27/99 3. Eaton Biconnical Antenna Model 94455-1 20-200 MHz Serial No. 0997 Cal. 10/30/98 4. Electro-Metric Dipole Kit, 20-1000 MHz, Model TDA-30 10/31/98 5. Electro-Metric Horn 1-18 GHz, Model RGA-180, Cal. 10/30/98 6. Electro-Metric Antennas Model TDA-30/1-4,Cal. 10/15/98 7. Electro-Metric Line Impedance Stabilization Network Model No. EM-7821, Serial No. 101; 100KHz-30MHz 50uH. Cal.11/19/98 8. Electro-Metric Line Impedance Stabilization Network Model No. EM-7820, Serial No. 2682; 10KHz-30MHz 50uH. Cal. 11/19/98 9. Special low loss cable was used above 1 GHz 10. Tenney Temperature Chamber TEST PROCEDURE GENERAL: This report shall NOT be reproduced except in full without the written approval of TIMCO ENGINEERING, INC. RADIATION INTERFERENCE: The test procedure used was ANSI STANDARD C63.4-1992 using a HEWLETT PACKARD spectrum analyzer with a prese- lector. The bandwidth of the spectrum analyzer was 100 kHz with an appropriate sweep speed. The analyzer was calibrated in dB above a microvolt at the output of the antenna. The resolution bandwidth was 100KHz and the video bandwidth was 300KHz. The ambient temperature of the UUT was 80oC with a humidity of 76%. FORMULA OF CONVERSION FACTORS: The Field Strength at 3m was estab- lished by adding the meter reading of the spectrum analyzer (which is set to read in units of dBuV) to the antenna correction factor sup- plied by the antenna manufacturer. The antenna correction factors are stated in terms of dB. The gain of the Preselector was accounted for in the Spectrum Analyzer Meter Reading. Example: Freq (MHz) METER READING + ACF = FS 33 20 dBuV + 10.36 dB = 30.36 dBuV/m @ 3m APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T REPORT #: F:\CUS\D\DBL\DLB186A9.RPT PAGE #: 1 TEST PROCEDURES CONTINUED APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T ANSI STANDARD C63.4-1992 10.1.7 MEASUREMENT PROCEDURES: The unit under test was placed on a table 80 cm high and with dimensions of 1m by 1.5m. The table used for radiated measurements is capable of continuous rotation. When an emission was found, the table was rotated to produce the maximum signal strength. At this point, the antenna was raised and lowered from 1m to 4m. The antenna was placed in both the horizontal and vertical planes. The situation was similar for the conducted measurement except that the table did not rotate. The EUT was setup as described in ANSIC63.4-1992 with the EUT 40 cm from the vertical ground wall. CIRCUIT_DESCRIPTION: The DK-902-T is a push-to-talk transciever. On the initial push it sends a doorbell chime to the companion unit inside. The signal comes on the antenna to the receiver to RF amplifier Q1. From Q1 the signal goes through a double tuned circuit to the intregrated circuit IC1, which is a mixer, IF amplifier, Second mixer and detector, and squelch circuit. The output of IC1 is fed to Q8 via R24 which is the squelch switch. From Q8 the signal is fed to IC2 the audio output amplifier whichis connected to the speaker. In the transmit mode the microphonecan only be activated if Q6 is not shorting it out. From MIC the audio is fed IC3. The output of IC3 is connected to the modulation control VR2 which varies the voltage to D2 a varicap. The modulated signal leaves the crystal controlled oscillator and is coulped through C15 to RF amplifier Q3 & Q2. From Q2 the signal is fed through a double tuned circuit L6 and then to L1 and the antenna. ANTENNA_AND_GROUND_CIRCUITRY This unit makes use of a internal antenna. The antenna is inductive- ly coupled. This unit is powered from four 1.5V battery. No ground connection is provided. The unit relies on the ground tract of the printed circuit board. APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T REPORT #: F:\CUS\D\DBL\DLB186A9.RPT PAGE #: 2 APPLICANT: DOUBLE KEEN INDUSTRIAL LTD. FCC ID: OLTDK-902-T NAME OF TEST: RADIATION INTERFERENCE RULES PART NO.: 15.235 REQUIREMENTS: CARRIER FREQUENCY WILL NOT EXCEED 80 dBuV/m AT 3M. OUT-OF-BAND EMISSIONS SHALL NOT EXCEED: 30 - 88 MHz 40.0 dBuV/M MEASURED AT 3 METERS 88 - 216 MHz 43.5 dBuV/M 216 - 960 MHz 46.0 dBuV/M ABOVE 960 MHz 54.0 dBuV/M TEST DATA: PEAK EMISSION METER READING COAX ANTENNA FIELD FREQUENCY AT 3 METERS LOSS CORRECTION STRENGTH MARGIN ANT. MHz dBuV dB FACTOR dB dBuV/m@3m dB POL. 49.86 44.90 0.25 10.99 56.14 23.86 V 149.65 14.50 0.80 16.90 32.20 11.30 V 199.50 16.80 0.90 12.65 30.35 13.15 V 249.40 11.70 1.20 13.36 26.26 19.74 H 299.30 11.30 1.40 15.66 28.36 17.64 H 349.20 14.00 1.40 15.53 30.93 15.07 V 399.10 15.50 1.40 16.97 33.87 12.13 V 449.00 25.10 1.60 18.13 44.83 1.17 V 498.90 22.40 1.60 19.27 43.27 2.73 V SAMPLE CALCULATION: F…

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