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SERVICE MANUAL UHF FM TRANSCEIVER LPD FM TRANSCEIVER...
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<SAMPLE ORDER> 0910049951 PCB B-5109B IC-4008A MAIN UNIT 5 pieces 8810009780 Screw PH BO M2x6 ZK IC-4008A Chassis 10 pieces Addresses are provided on the inside back cover for your convenience. REPAIR NOTES 1. Make sure a problem is internal before disassembling the transceiver.
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SECTION 1 SPECIFICATIONS [ITA], [ITA-1] [CSA], [CSA-1] Number of channels 69 channel (simplex; 433.075–434.775) Type of emission 16K0F3E Frequency stability ±2500 Hz (±5.7 ppm) Frequency resolution 25 kHz Power supply requirements AA(R6) dry, alkaline;or optional BP-202 (negative ground) Current drain less than 140 mA less than 500 mA Operating temperature range...
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CHANNEL FREQUENCY LIST Channel No. Frequency (MHz) Channel No. Frequency (MHz) Channel No. Frequency (MHz) 433.0750 433.6500 434.2250 433.1000 433.6750 434.2500 433.1250 433.7000 434.2750 433.1500 433.7250 434.3000 433.1750 433.7500 434.3250 433.2000 433.7750 434.3500 433.2250 433.8000 434.3750 433.2500 433.8250 434.4000 433.2750 433.8500 434.4250 433.3000...
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SECTION 2 INSIDE VIEWS • MAIN UNIT TOP VEIW BOTTOM VEIW Audio amplifier (IC9: NJM2070M) EEPROM T+3 Regurator (IC3: X24C01AS) (Q28: 2SB798) +3 Regurator (IC6: S-81230SG) (IC1: PD753036GK) R+3 Regurator (Q18: 2SA1586) • RF UNIT TOP VIEW BOTTOM VIEW FM IF IC (IC2: TA31136FN) Reference oscilletor (X1: CR-633 21.25 MHz)
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SECTION 3 DISASEMBLY INSTRUCTIONS • • REMOVING THE MAIN UNIT REMOVING THE REAR PANEL Unscrew 2 screws, Unscrew 1 screw , and 4 screws Remove the PTT rubber, Remove the rear panel in the direction of the arrow. Unsolder 2 points, , and remove the MAIN unit.
SECTION 4 CIRCUIT DESCRIPTION 4-1 RECEIVER CIRCUITS 4-1-4 2nd MIXER AND DEMODULATOR CIRCUITS (RF UNIT) 4-1-1 ANTENNA SWITCHING CIRCUIT (RF UNIT) The 2nd mixer circuit converts the 1st IF signal to a 2nd IF Received signals from the antenna connector are passed signal.
4-1-6 SQUELCH CIRCUIT (RF AND MAIN UNITS) 4-2-3 DRIVE/POWER AMPLIFIER CIRCUITS (1) NOISE SQUELCH (RF UNIT) The noise squelch circuit cuts out AF signals when no RF sig- The amplifier circuit amplifies the VCO oscillating signal to nals are received. By detecting noise components in the AF the output power level.
4-4 POWER SUPPLY CIRCUITS Port Description VOLTAGE LINE number name Outputs data signals to the PLL IC (RF LINE DESCRIPTION PLLDA unit; IC1). BATT The voltage from the connected battery pack. Outputs strobe signals for the PLL IC PLLST Common 3 V converted from the BATT line at (RF unit;...
SECTION 5 ADJUSTMENT PROCEDURES 5-1 PREPARATION REQUIRED TEST EQUIPMENT EQUIPMENT GRADE AND RANGE EQUIPMENT GRADE AND RANGE Output voltage : 4.5 V DC Frequency range : 300–3000 Hz DC power supply Audio generator Current capacity : 1 A or more Measuring range : 1–500 mV Measuring range...
5-2 ADJUSTMENT ADJUSTMENT MEASUREMENT POINT ADJUSTMENT ADJUSTMENT CONDITION VALUE UNIT LOCATION UNIT ADJUST REFERENCE • Operating channel : Ch 35 Loosely couple a fre- 433.925000 MHz FREQUENCY • Transmitting panel quency counter to the antenna. OUTPUT • Operating channel : Ch 35 Connect an RF power 9 mW [ITA/–1] R206...
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Reference frequency adjustment FM deviati R206 Output power adjustment RF test por TEST ENTERING THE ADJUSTMENT MODE q Turn the transceiver power OFF. w While connecting the "TEST" to GND, then turn power ON. 5 - 3...
SECTION 11 VOLTAGE DIAGRAM 11-1 MAIN UNIT : COMMON : TX R100 R101 R102 : RX 100 k 100 k 100 k 100 k 100 k 100 k J4 4-175638-4 to RF unit J2 SO : SQL OPEN UNLK SC : SQL CLOSE BATT LON : LIGHT ON DATA...
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