N6MEH-465Family Radio Transceiver

THEORY OF OPERATION 1. SEMICONDUCTORS AND FUNCTION 1.1 IC COMPLEMENT REF.NO TYPE MANUFACTURER FUNCTION IC201 IC501 IC801 IC401 IC402 IC403 IC301 IC902 IC901 DBL-5018 TB31202FN TK11235 KIA324F KIA324F KIA324F NJM386M 24C02S TMP87CH21DF DAE WOO THOSHIBA TPKO JAPAN KEC KEC KEC JRC PRO-CHIPS TOSHIBA IF DEMODULATOR PLL IC REG ULATOR MIC AMP R/TX AUDIO FILTER LOW PASS FILTER AUDIO AMP EEPROM CPU 1.2 TRANSISTOR COMPLEMENT REF.NO TYPE MANUFACTURER FUNCTION Q101 Q102 Q103 Q5,Q6 Q7 Q8 Q702 Q701 Q704 Q802 Q801 Q803 Q403 Q402 Q401 Q301 Q302 Q303 Q901 AT31625 BFQ67W BFQ67W BFQ67W BFQ67W MMBC1321 2SC4226 2SC4226 KTC3875 KRA110S KRA110S KRA110S KRA110S KTC3875 KRA110S KTA1505 KRC111S KRA110S KRC245S H. P VISHAY VISHAY VISHAY VISHAY MOTOROLA NEC NEC KEC KEC KEC KEC KEC KEC KEC KEC KEC KEC KEC FINNAL RF AMP DRIVER AMP PREDRIVER AMP LNA 1'ST MIXER IF AMP VCO BUFFER AMP VCO OSC REG ULATOR RX B+ SW TX EN2 SW TX EN1 SW CTCSS B+ SW TONE AMP AUDIO MUTE SW AUDIO MUTE SW PTT SW LAMP SW MIC AMP MUTE SW ; REMARKS. KEC : KOREA ELECTRONICS CO., LTD. DAE WOO : DAE WOO ELECTRONICS CO., LTD TOSHIBA : TOSHIBA JAPAN CO., LTD MOTOROLA : MOTOROLA CO., LTD JRC : NEW JAPAN RADIO CO,. LTD PRO-CHIPS : JAPAN MICROCHIP CO., LTD NEC : NEC JAPAN CO., LTD H.P : HELWETT PACKARD CO., LTD VISHAY : VISHAY SEMI CONDUCTOR MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT 7A-7D 2. DESCRIPTION OF FREQUENCY DETERMINING AND STABILING CIRCUIT 2.1 INTRODUCTION THE FREQ UENCIES FOR TRANSMITTER AND RECEIVER LOCAL FREQ UENCIES ARE ALL DRIVED FROM A SINGLE 21.25 [MHz] CRYSTAL BY MEANS OF A PHASE LOCKED LOOP. THE FIRST LOCAL OSCILLATOR FREQUENCIES ARE 440.8625 [MHz] (CH.1) TO 446.0125 [MHz] (CH.14). THE SECOND LOCAL FREQUENCY IS FIXED AT 21.25 [MHz] TO GENERATE SECOND IF 455 [KHz]. DURING TRANSMIT, THE VCO OF THE PLL OPERATES 462.5625 [MHz] (CH.1) TO 467.7125[MHz](CH.14). +−−−−−−−−−−−+ +−−−−−−−−−−−−−−−−−−−−+ | Θ701 | | Θ702 | ΤΟ ΤΡΑΝΣΜΙΤΤΕΡ | +−−−−−−−+−−−−−−+ +−−−−−−−−−−+−−−−−−−−−−−−−− | ςΧΟ | | |ΒΥΦΦΕΡ ΑΜΠ | | +−−−−−−−−−−−+ | +−−−−−−−−−−−−−−−−−−−−+ | 462.5625 [ΜΗζ](ΧΗ.1) 462.5625 [ΜΗζ](ΧΗ.1) ~ 467.7125 [ΜΗζ](ΧΗ.14) ~ 467.7125[ΜΗζ](ΧΗ.14) THE VCO OPERATING FREQUENCY FOR THE RECEIVER IS 440.8625 [MHz] (CH.1) TO 446.0125 [MHz] (CH.14) AS THE FIRST LOCAL OSCILLATOR, INJECTED THRO UG H THE BUFFER AMP Q702 INTO THE FIRST TR MIXER Q7 2.2 DESCRIPTIONS OF EACH BLOCK (1) INTRODUCTION THE SY NTHESIZER IS IMPLEMENTED WITH THE FOLLOWING COMPONENTS : PLL IC (IC501), 2’nd OSC (X501), VCO, VARICAP DIODE (D701) THE IC501 IS A CMOS LSI THAT INCLUDES PRESCALLER, THE Q701, D701, C713, C716, C711, L703 ARE CLAPP OSCILLATOR CIRCUIT TO OPERATE AS A VCO OF THE IC501. THE Q705 IS A SWITCHING TRANSISTOR TO CONNECT OR DISCONNECT THE TUNING CAPACITOR IN THE VCO OSCILLATOR TANK CIRCUI T FOR TRANSMITTER OR RECEIVER. THE Q702 WORKS AS A BUFFER AMP FOR RX LOCAL FREQUENCIES AND TX CARRIER GENERATI NG FREQ UENCIES. (2) REFERENCE FREQUENCY THE CRYSTAL, X501(21.25 [MHz] ) AND OTHER COMPONENTS AT PIN.10 AND 11 OF IC501 CAN MAKE A REFERENCE FREQ UENCY OSCILLATOR WITH INTERNAL AMPLIFIER. (3) VCO THE Q701 AND SURRO UNDI NG PARTS ARE CO NSISTI NG A CLAPP OSCILLATOR WORKS AS A VCO OF IC501 WITH APPROPRIATE CO NTROL VOLTAGE ON D701, THE VCO CAN BE OSCILLATE OVER THE REQUIRED RANGE OF 440.8625 [MHz] TO 467.7125 [MHz]. (4) PROGRAMMABLE DIVIDER AND ITS CONTROL THE PROGRAMMABLE INPUTS FOR EACH CHANNELS ARE SETTED IC INSIDE. EACH INPUT SIGNAL TO CONTROL THE PLL IC501 IS DONE WITH THE PROVIDED (CPU IC 901) KEY MATRIX INPUT PI NS – PI N17 TO PIN20 AND FOR EACH KEY INPUT, AN INTERNAL CODE CONVERT EPROM PROVIDES THE APPROPRIATE BINARY CONTROL TO THE IC501 FOR THAT CHANNEL. SINCE THE BI NARY NUMBER NECESSARY TO CHANGE DURI NG TRANSMIT AND RECEIVE, AN ADDITIONAL BIT IS REQUIRED AT PIN.33 OF IC901 TO ALLOW THE ROM TO RECOGNIZING THE STATUS IS TX OR RX. DURING TRANSMIT, THE PUSH TO TALK SWITCH MAKES PIN.33 OF CPU IC IS HI DIGITALLY UNDER TRANSMIT MODE. THE PROGRAMMABLE DIVIDER TO PLL IC501. THE IC501 OUTPUT IS FED TO THE PHASE DETECTOR FOR COMPARING WITH THE 6.25 [KHz] REFERENCE FREQ UENCY INSIDE (5) PHASE DETECTOR AND VCO CONTROL THE PHASE DETECTOR IS A DIGITAL PHASE COMPARATOR WHICH COMPARES THE PHASE OF THE REFERENCE SIG NAL WITH PROGRAMMABLE DIVIDER O UTPUT SQ UARE WAVES AND DEVELOPS A SERIES OF PULSES WHOSE DC LEVEL DEPENDS O N THE PHASE ERROR OF EACH SIG NAL. THE PHASE DETECTOR PULSE O UTPUT IS FED TO AN ACTIVE LOW PASS FILTER, AND FED TO VARICAP D701 CO NTROL THE VCO FREQ UENCY. (6) TRANSMITTER / RECEIVER BUFFER AMP OUTPUT SIGNAL OF Q701 IS FED INTO THE BUFFER AMP Q702 TO INCREASE THE STRENGTH OF TX CARRIER FREQ UENCY AND 1’st LOCAL FREQ UENCIES. (7) SWITCHING OF TUNING CAPACITOR IN VCO THE VCO CIRCUIT MUST TUNE WITH A WIDE RANGE OF FREQUENCIES 462.5625<467.7125 [MHz] FOR TRANSMITTER AND 440.8625<446.0125 [MHz] FOR RECEIVER. TO COMPLY ABOVE RANGE OF VCO, THE TUNI NG CAPACITANCE SHO ULD SWITCHED FOR TRANSMISSION OR RECEPTION. THE TUNING CIRCUIT CONSISTS WITH D701, C716, L703, C711, Q701, C706, C710 (8) RECEIVER LOCAL OSCILLATOR OUTPUTS 1’st MIXER : THE OUTPUT SIGNALS OF Q702 IS INJECTED TO THE SOURCES OF 1st MIXER Q7 IN THE 1’st IF MIXER SECTION. 2’nd MIXER : THE OUTPUT OF 21.25 [MHz] OSCILLATOR CIRCUIT WITH X101 IS INJECTED INTO THE IC501. INCOMING IF SIGNAL AND 21.7 [MHz] SIGNAL ARE MIXED INSIDE THE IF IC TO EXTRACT 2’nd IF SIGNAL 450 [KHz]. FM SIGNALS ARE RECOVERED WITH ENVELOPE DETECTOR. 2.3 FREQUENCY STABILITY LET : Fo=CRYSTAL OSCILLATOR FREQ UENCY Fr=PHASE DETECTOR REFERENCE FREQ UENCY Fvco=VCO FREQUENCY Ft=TRANSMIT FREQUENCY THEN : Fr=Fo/ 2048 AND UNDER LOCKED CO NDITIONS : Fr = Fvco / N Where , "N" IS THE DIVIDE RATIO OF PROGRAMMABLE DIVIDER. THEN : Fvco = N X Fr FROM WHICH IT CAN BE SEEN, THE PERCENTAGE ERROR IN Ft IS THE SAME AS THE PERCENTAGE ERROR IN Fo. THE STABILITY OF THE CRYSTAL OSCILLATOR IS DETERMINED PRIMARILY BY THE CRYSTAL ITSELF AND HAVI NG PASSIVE COMPO NENTS OF THE OSCILLATOR. THE CHOICE OF CRYSTAL AND COMPONENTS IS SUCH THAT THE REQUIRED FREQUENCY STABILITY IS MAINTA…

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2.4 DESCRIPTION OF OTHER CIRCUITS TRANSMITTER (1) RF AMPLIF ICATION THE OUTPUT OF BUFFER AMP Q702 IS FED THROUGH TUNING C119 TO THE BASE OF PRE DRIVER AMP Q103. THE O UTPUT IS THEN SUPPLIED THRO UG H CAPACITOR C116 TO RF DRIVER AMP Q102. THE OUTPUT OF Q102 IS SPLITTED WITH TUNING CIRCUIT L107, C111, C112, L113, AND GOES TO THE BASE OF FINAL RF AMP Q101. THE OUTPUT OF Q101 IS SUPPLIED TO THE ANTENNA THROUGH L-C TUNING CIRCUIT. (2) CIRCUIT FOR SUPPRESSION OF SPURIOUS RADIATION THE TUNING CIRCUIT BETWEEN THE OUTPUT OF FINAL AMP Q101 AND ANTENNA, 4-STAGE "PHI TYPE" NETWORK L101, L102, L103, C101, C102, C103, C104, SERVES AS A SPURIOUS RADIATION SUPPRESSOR. THIS NETWORK ALSO SERVES TO MATCH THE IMPEDANCE BETWEEN TX FINNAL POWER AMP Q101 AND THE ANTENNA. (3) MAXIMUM MODULATION CONTROL MODULATION SIG NALS ARE FILTERED WITH RC NETWORK AND GOES TO THE AUDIO AMP IC401 TO MAKE NOMINAL SIGNAL LEVEL TO ACHIEVE WANTED MODULATION. TO CONTROL INCOMING AUDIO SIGNAL, IC806 PIN14 AND CORRESPONDING LEVEL LIMITTING CIRCUIT CONTROLS WITH RV401. ADJUST RV401 SHALL NOT EXCEED ± 2.5KHz DEVATIO N UNDER.1KHZ AF 20dB UP FROM 1.5KHZ DEVATIO N LEVEL I NPUT. RECEIVER (1) RF AMP Q5, Q6 AMPLIFY RF SIGNAL FROM ANTENNA,THE AMPLIFIED RF SIGNAL IS FED THROUGH TUNING LC FILTER L203, L204 TO THE BASE OF MIXER AMP Q7, ALSO VCO SOURCE'S FREQ UENCY LOWER 21.7MHz THAN THE FREQ UENCY OF EACH CHANNEL IS SUPPLIED TO MIXER (2) THE SO URCE OF 21.7MHz FREQ UENCY PASSED TUNI NG COIL L208, C237 IS FED THRO UG H XF201 TO IF AMP Q8. (3) THE 450KHz FREQUENCY SIGNAL PRODUCED FROM IC201 BY MIXING THE OUTPUT SOURCE OF XF201 21.7MHz FILTER AND THE SOURCE OF 21.25MHz FREQUENCY FROM CRYSTAL OSCILLATOR X501. (4) THE IC201 IS A FM DETECTOR WHICH PRODUCES AUDIO SIGNAL THE AUDIO SIGNAL (IC201 PIN 9) IS FED THROUGH C229 TO AUDIO POWER AMP (IC301). FOR DRIVING SPEAKER. MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT # 8

ALIGNMENT INSTRUCTIONS 1. ALIGINMENT LAYOUT [CPU SECTION ] [ RF SECTION ] 2. TEST EQUIPMENT REQUIRED 1) CPU and Phase Locked Loop Section  Frequency Counter α DC Power Supply β DC Volt Meter χ Oscilloscope 2) Transmitter Section  RF Power Meter(RF SSVM) α 50 ∧ Load(non-inductive) β RF Attenuator χ Oscilloscope δ Audio Generator ε DC Power Supply φ Spectrum Analyzer γ Frequency Counter η Modulation Meter 3) Receiver Section MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT # 9A-9C  RF Signal Generator α AF Level Meter β Distortion Meter χ DC Power Supply • Sinadder Meter • Oscilloscope • 16 Ohm 1w Dummy Load 3. ALIGNMENT PROCEDURE 1) PHASE LOOKED LOOP AND CPU SECTION STEP SETTI NG CONNECTIO N ADJUST ADJUST FOR 1 Frequency adjustment ; Mode : Receive Volume : Optional Squelch : Optional CH Selector : 1 Frequency counter To output pin_10 of IC501 (Figure-1) CT501 21.25MHz ± 100Hz 2 CPU Voltage check ; Mode : Receive Volume : Optional Squelch : Optional CH Selector : 1 Connect DC volt. Meter to R509 On Cpu Board. Indication on DC voltmeter must be 0.5V. 2) TRANSMITTER SECTION STEP SETTI NG CONNECTIO N ADJUST ADJUST FOR 1 RF Power stage ; Mode : Transmit Volume : Optional Squelch : Optional CH Selector : 3 Connect dummy load and RF power meter to the external ANT-jack on the Set (Figure-2) P ower meter(0.5 ± 0.1W) 2 Second harmonic check ; Mode : Transmit Volume : Optional Squelch : Optional CH Selector : 3 Connect RF power meter with dummy load to spectrum analyzer through coupler/-40dB atten. to EXT-ANT. Jack on the set (Figure-3). At no modulation, compare the level of fundamental freq-spectrum to the level of harmonic freq-spectrum. Suppression of the 2nd harmonic Freq. level must be lower than 60dB. Check for the other channel's 3 Frequency check ; Mode : Transmit Volume : Optional Squelch : Optional CH Selector : 1 Connect dummy load and frequency counter through coupler to RF power meter. Also connect power meter to EXT-ANT. jack on the set. (Figure-4) Make sure that the indication of the transmitter freq. Is 462.5625MHz ± 2.5PPM on the frequency counter. 4 MAX deviation check ; Mode : Transmit Volume : Optional Squelch : Optional CH Selector : 1 Connect dummy load and modulation meter through coupler to RF power meter. Also connect power meter to EXT-ANT. jack on the set. (Figure-6) RV-401 adjust RV401 so that the indication of the modulation analyzer is 2.3 ± 0.2KHz. 3) RECEIVER SECTION STEP SETTI NG CONNECTIO N ADJUST ADJUST FOR 1 RX senstivity ; Mode : Receiver Volume : Half clockwise Sque lc h : Turn to counterclockwise CH Selector : 1 SSG : 462.5625MHz 1KHZ AF 1.5KHZ DEV. 0.22uV Connect RF signal Generator to external ANT. Jack. Connect SSVM,Sinadder and Distortion meter across EXT-Speaker out jack with 16 ∧ dummy load (Figure-5) Adjust the parts of tuning circuitry for 12 • SINADDER

Safety Information For FRS UNIT Your wireless handheld portable transceiver contains a low power transmitter. When the PTT button is pushed it sends out radio frequency (RF) signals. This device is authorized to operate at a duty factor not to exceed 50%. In August 1996, the Federal Communications Commission (FCC) adopted RF exposure guidelines with safety levels for hand-held wireless devices. Important: To maintain compliance with the FCC’ s RF exposure guidelines, hold the transmitter at least 1 inch (2.5 centimeters) from your face and speak in a normal voice, with the antenna pointed up and away. If you wear the handset on your body while using the headset accessory, DO NOT TRANSMIT. The MAYCOM supplied belt clip is for storage purposes ONLY. Use only the supplied antenna. Unauthorized antennas, modifications, or attachments could damage the transmitter and may violate FCC regulations. Normal Position: Hold the transmitter approximately 1” from your face and speak in a normal voice, with the antenna pointed up and away.

TABLE OF CONTENTS LIST APPLICANT: MAYCOM CO., LTD. FCC ID: N6MEH-465 TEST REPORT: PAGE 1......COVER SHEET - GENERAL INFORMATION & TECHNICAL DESCR. PAGE 2......TECHNICAL DESCRIPTION CONTINUED & RF POWER OUTPUT PAGE 3......MODULATION CHARACTERISTICS AND OCCUPIED BANDWIDTH PAGE 4......METHOD OF MEASURING OCCUPIED BANDWIDTH PAGE 5-6....UNWANTED RADIATION PAGE 7......FREQUENCY STABILITY PAGE 8......LIST OF TEST EQUIPMENT EXHIBITS CONTAINING: EXHIBIT 1.........FCC ID LABEL SAMPLE EXHIBIT 2.........SKETCH OF LABEL LOCATION EXHIBIT 3A........EXTERNAL FRONT AND REAR VIEW PHOTOGRAPHS EXHIBIT 3B........EXTERNAL TOP AND BOTTOM VIEW PHOTOGRAPHS EXHIBIT 3C........EXTERNAL SIDE VIEW PHOTOGRAPHS EXHIBIT 3D........INTERNAL COMPONENT AND COPPER VIEW PHOTOGRAPHS EXHIBIT 4.........BLOCK DIAGRAM EXHIBIT 5.........SCHEMATIC EXHIBIT 6A-6W.....USER'S MANUAL EXHIBIT 7A-7D.....THEORY OF OPERATION EXHIBIT 8.........CIRCUIT DESCRIPTION EXHIBIT 9A-9C.....TUNING PROCEDURE EXHIBIT 10........AUDIO LOW PASS FILTER EXHIBIT 11........AUDIO FREQUENCY RESPONSE GRAPH EXHIBIT 12A.......MODULATION LIMITING PLOT - 300 Hz EXHIBIT 12B.......MODULATION LIMITING PLOT - 1000 Hz EXHIBIT 12C.......MODULATION LIMITING PLOT - 3000 Hz EXHIBIT 13........OCCUPIED BANDWIDTH CW PLOT EXHIBIT 14........OCCUPIED BANDWIDTH PLOT APPLICANT: MAYCOM CO., LTD. FCC ID: N6MEH-465 DATE: JUNE 2, 2000 REPORT #: T:\CUS\M\MAY\193K0\MAY193K0.RPT PAGE: TABLE OF CONTENTS GENERAL INFORMATION REQUIRED FOR TYPE ACCEPTANCE 2.1033(c)(1)(2)MAYCOM CO., LTD. will manufacture the FCCID: N6MEH-465 FAMILY RADIO SERVICES 14 CHANNEL TRANSCEIVER in quantity, for use under FCC RULES PART 95. MAYCOM CO., LTD. MAYCOM B/D, 280-5 SUKSU-DONG MANAN-GU, ANYANG-CITY, KYONGKI-DO, KOREA 2.1033 (c) TECHNICAL DESCRIPTION 2.1033(c)(3) Instruction book. A draft copy of the instruction manual is included as exhibit 6A-6W. 2.1033(c) (4) Type of Emission: 10K0F3E 95.629 Bn = 2M + 2DK M = 3000 D = 2.0K Bn = 2(3.0)+2(2.0) = 10.0K Authorized Bandwidth 12.5KHz 2.1033(c)(5) Frequency Range: 1. 462.5625 8. 467.5625 95.627 2. 462.5875 9. 467.5875 3. 462.6125 10. 467.6125 4. 462.6375 11. 467.6375 5. 462.6625 12. 467.6625 6. 462.6875 13. 467.6875 7. 462.7125 14. 467.7125 MHz 2.1033(c)(6)(7)Power Output shall not exceed 0.500Watts effective 95.637 radiated power. There can be no provisions for 95.647 increasing the power or varying the power. The Maximum Output Power Rating: 250 milliWatts effective radiated power. 95.645 The antenna is an integral part to the unit, it cannot be removed without rendering the unit inoperative. In order to remove the antenna the case must unscrewed, then the PCB assemblies must be removed then the antenna can be removed. 2.1033(c)(8) DC Voltages and Current into Final Amplifier: FINAL AMPLIFIER ONLY Vce = 4.5 Volts DC Ice = 0.12A. Pin = 0.54 Watts 2.1033(c)(9) Tune-up procedure. The tune-up procedure is included as exhibit 9A-9C. DATE: JUNE 2, 2000 REPORT #: T:\CUS\M\MAY\193K0\MAY193K0.RPT PAGE #: 1 TECHNICAL DESCRIPTION CONTINUED 2.1033(c)(10) Complete Circuit Diagrams: The circuit diagram is included as exhibit 5 of this report. The block diagrams are included as exhibit 4 of this report. 2.1033(c)(11) A photograph or a drawing of the equipment identifica- tion label is included as exhibit No. 1. 2.1033(c)(12) Photographs(8"X10") of the equipment of sufficient clarity to reveal equipment construction and layout, including meters, labels for controls and including any view under shields are included as exhibits 3A-3D. 2.1033(c)(13) Digital modulation is not allowed. 2.1033(c)(14) The data required by 2.1046 through 2.1057 is submitted below. 2.1046(a) RF power output. 95.637 RF power is measured by measuring the radiated power at 3 meters and then replacing the transmitter with a signal generator to determine the effective radiated power. The ERP shall not exceed 0.500 Watts. MEASURED POWER OUTPUT = 250 milliWatts ERP R.F. POWER OUTPUT HP TEST SET UP Spectrum Analyzer /-------\ /-----------------\ | | | | TRANSMITTER | | | | | UNDER TEST WITH | \--| | | INTERNAL ANTENNA| | | | \-----------------/ | | | | | \-------/ | | |<-- 3.0 meters-->| /-------------\ | SIGNAL | DIPOLE | Tuned, Calibrated | GENERATOR | ANTENNA | Antenna which may | |----------/ be raised from 1 \-------------/ to 4 meters above ground and changed in polarization Equipment placed 1 meter above ground on a rotatable platform. APPLICANT: MAYCOM CO., LTD. FCC ID: N6MEH-465 DATE: JUNE 2, 2000 REPORT #: T:\CUS\M\MAY\193K0\MAY193K0.RPT PAGE #: 2 2.1047(a)(b) Modulation characteristics: AUDIO FREQUENCY RESPONSE The audio frequency response was measured in ac- cordance with TIA/EIA Specification 603. The audio frequency response curve is shown on the next page. The audio signal was fed into a dummy microphone circuit and into the microphone connector. The input required to produce 30 percent modulation level was measured. 2.1047(b) Audio input versus modulation The audio input level needed for a particular per- percentage of modulation was measured in accor- dance with TIA/EIA Specification 603. The audio input curves versus modulation are on the following pages. Curves are provided for audio input frequen- cies of 300, 1000, and 3000 Hz. 95.635(b) Post Limiter Filter The filter must be between the modulation limiter and the modulated stage. At any frequency between 3 & 20KHz the filter must have an attenuation of 60log (f/3) greater than the attenuation at 1KHz. See Exhibit 10. 2.989(c) EMISSION BANDWIDTH: 95.633(b)(1)(3)(7) Data in the plots shows that the sidebands from greater than 50% to 100% of the authorized bandwidth must be attenuated by at least 25dB and from 100 to 250% the sidebands must be attenuated by at least 35dB. Beyond 250% the sidebands must be attenuated by at least 43+log10(TP). The transmitter was modulated with 2500 Hz, adjusted for 50% modulation plus 16 dB. The spectrum analyzer was set with the unmodulated carrier at the top of the screen. The test procedure diagram and occupied b…

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Maycom Co. LTD. EH-465 0 10 20 30 40 50 60 100100010000100000 Frequency rms mVolts audio response MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT # 11

Modulation Limiting Maycom Co. LTD. EH-465 0 500 1000 1500 050100150200 rms mVolts Deviation 300 Hz MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT # 12A

Modulation Limiting Maycom Co. LTD. EH-465 0 500 1000 1500 2000 2500 3000 051015202530 rms mVolts Deviatio n 1000 Hz MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT # 12B

Modulation Limiting Maycom CO. LTD. EH-465 0 200 400 600 800 1000 024681012 rms mVolts Deviation 3000 Hz MAYCOM CO., LTD. FCC ID: N6MEH-465 JOB # 193K0 EXHIBIT # 12C