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INTRODUCTION This service manual describes the latest service information for the IC-F4TR UHF TRUNKED RADIO at the time of publication. To upgrade quality, all electrical or mechanical parts and internal circuits are subject to change without notice or obligation. DANGER...
SECTION 1 SPECIFICATIONS ‘ ‘ GENERAL Frequency coverage : 450.000–490.000 MHz Type of emission : 16K0F3E (25 kHz) 11K0F3E (12.5 kHz) : 50 Ω nominal Antenna impedance Power supply requirement : 9.6 V DC (negative ground; supplied battery pack) Current drain at 9.6 V DC (approx.) : Transmit 1.4 A (at 4 W) 700 mA (at 1W)
SECTION 3 DISASSEMBLY INSTRUCTION • Removing the cassis panel 1 Unscrew 1 nut A, and remove 1 nob B. 2 Unscrew 2 screws C. 3 Take off the chassis in the direction of the arrow. 4 Unplug J6 to separate front panel and chassis. Chassis (nickel, 2 mm) ×...
SECTION 4 CIRCUIT DESCRIPTION 4-1 RECEIVER CIRCUITS The signals from the RF circuit are mixed at the 1st mixer (Q13) with a 1st LO signal coming from the VCO circuit to 4-1-1 ANTENNA SWITCHING CIRCUIT produce a 47.25 MHz 1st IF signal. Received signals are passed through the low-pass filter (L1–L3, C3–C5, C7).
The applied AF signals are amplified at the AF power ampli- 4-2-2 MODULATION CIRCUIT fier circuit (IC5, pin 4) to obtain the specified audio level. The The modulation circuit modulates the VCO oscillating signal amplified AF signals, output from pin 10, are applied to the (RF signal) using the microphone audio signal.
When the driving current is increased, input voltage of the 4-4 POWER SUPPLY CIRCUITS differential amplifier (IC19, pin 3) will be increased. In such VOLTAGE LINE cases, the differential amplifier output voltage (pin 4) is Line Description decreased to reduce the driving current. The voltage from the attached battery pack.
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4-5 PORT ALLOCATIONS CPU (IC17) Port Port Description Description number name number name Input port for the reset signal. BEEP Outputs beep audio signals. Input port for writing control signal. Outputs T5 regulator control signal. Low : Writing to CPU (IC17) Low: While transmitting CSHIFT Outputs CPU clock shift signal.
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SECTION SECTION 8 PARTS LIST SEMI-CONDUCTOR INFORMATIONS 8 - 1 TRANSISTORS AND FET’S NAME SYMBOL INSIDE VIEW NAME SYMBOL INSIDE VIEW NAME SYMBOL INSIDE VIEW NAME SYMBOL INSIDE VIEW 2SK2596BXTL HVU350TRF 2SA1362-GR XP6401 B2 E2 3SK239XR - TL MA77 2SB1132 - R 3SK241 - R XP6501 - AB 3SK293...
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SECTION 9 BOARD LAYOUTS The combination of this page and the next page shows 9 - 1 MAIN UNIT the unit layout in the same configuration as the actual P.C. Board. MICROPHONE • TOP VIEW VR unit VLOUT VLIN to SP1 ANTENNA Surface 9 - 2 VR BOARD...
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The combination of this page and the previous page shows the unit layout in the same configuration as the actual P.C. Board. MICROPHONE • BOTTOM VIEW EXT. SP CLONE EXT. MIC Surface CHARGER • BOTTOM VIEW VL OUT MAIN unit VL IN Surface 9 - 2...
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