In this manual you can find all the information of product service. RED-RADIO reserve the rights to modify the product construction and specification without notice in order to enhance product performance and quality.
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All the RED-RADIO products are subject to the service warranty. After-sales service will be provided, and the length of warranty is stated by RED-RADIO. The radio and its accessories are all in the warranty. However, in one of the following cases, charge free service will be not available.
PT500-2 Service Manual Chapter 2 Radio Overview 1. PTT ( PUSH-TO-TALK) Button To make a call, press and hold the PTT button, then speak into the microphone in normal voice. Release the PTT button to receive signals. 2. Side Button 1 (Programmable Button) 3.
6. LED Indicator LED Indicates Status/Alert. Green LED lights when a carrier is detected in the current channel. Red LED lights during transmission. Orange LED flashes when receiving the Radio ID 5-Tone signaling or 2-Tone signaling or MDC signaling. Green LED flashes when scanning.
PT500-2 Service Manual Mode combinations Mode Function How to access User Mode For normal use Power on Data Reading and writing Receive instructions from frequency data and other Programming the PC functions mode Used to tune the radio Receive instructions from Test Mode using the PC.
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PT500-2 Service Manual 4. Turn on the power of the interphone. 5. Click on PT500 icon to perform the program. 6. In the main menu of the programming software, click on [Read] to read the parameters of the radio into the computer; click on [Write] to write the parameters set in the computer into the radio.
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PT500-2 Service Manual (20) RX squelch 9 close level (21) RX squelch 1 open level (22) RX squelch 1 close level (23) RSSI(-120dBm) (24) RSSI(-70dBm) Firmware Upgrading Mode The radio is equipped with an internal FLASH ROM, it can be upgraded if required.
PT500-2 Service Manual Chapter 4 Disassembly For Repair The radio is a kind of sophisticated communication equipment with small and fine mechanical structure. You should assemble and disassemble it carefully during the maintenance process. The Instruction for assembly and disassembly are as follows:...
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PT500-2 Service Manual Notice: * Do not short-circuit the battery terminals or dispose the battery in fire. * Do not disassemble the battery case. Installing/Removing Antenna, Channel Selector, Power/Volume Knob Screw the antenna out of the connector at the top of the radio by holding the bottom of the antenna and turn it counter clockwise until apart.
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PT500-2 Service Manual Install external speaker/MIC Open the cover of the jack for external speaker/MIC, and then insert the plug of the external speaker or microphone into the jack on the radio. When inserting the accessory plug, make sure it is properly aligned ( straight) to avoid internal damage to the connector in the radio.
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PT500-2 Service Manual Installing/Removing the Chassis, PCB...
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PT500-2 Service Manual 1. Remove the antenna, channel selector and power/volume knob and two screws under the channel selector and volume knob. 2. Screw off the two screws at the bottom of the radio by a hexagon screwdriver. 3. Pry up the aluminum shell by peaking a straight screwdriver in the cross-slot at the...
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PT500-2 Service Manual Exploded View of the Parts Parts No. Description Qty. 604PT50001001 Cabinet asm. 2010CU600004X Ear phone cabinet O-ring Φ5X1.5 2020PT500004X 304060250001X Volume screw M6X0.75X2.5 special shape brass 2010CU600006X Volume knob black 304070250001X Volume screw M7X0.75X2.5 special shape brass...
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PT500-2 Service Manual 7100500240471 Anntenna 2030CU600003X SMA RF socket O-ring Φ7X1.5 2020PT500003X 2010CU600005X radio top cover black 2020PT500002X 2 PIN power socket washer 301250607001X machine screw M2.5X6.0 PB(+) black Ni-plate 7110CLP02001 CLP-02 clip asm. 70600CB03001 Battery CB-03 (OR CB-05 70600CB05001) 301200807001X Machine screw M2.0X8.0...
PT500-2 Service Manual 604PT50001002 AL cabinet asm. 2030PT500001X AL cabinet 2010CU600005X Radio top cover black 2020PT500001X Cabinet waterproof ring orange 2020PT500002X Power socket washer 301250607001X Machine screw M2.5X6.0 2010CU600006X Volume knob 2010CU600007X Encoder knob 7110CLP02001 CLP-02 Clip Chapter 5 Circuit Description 5.1 Frequency configuration...
PT500-2 Service Manual Figure 5. 1 Frequency configuration 5.2 Receiver(Rx) The receiver is double conversion superheterodyne, designed to operate in the frequency range of 400 to 470MHz,The frequency configuration in Fig 2 Figure 5.2 Receiver section configuration Front End of Receiver...
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PT500-2 Service Manual The PWM wave is output by MCU composed of 58 foot and then commutated to adjustable voltage after filtering to change the capacity of varactor diode D905 D203 D206 D201 D202 and D204 to control the center frequency of BPF.
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PT500-2 Service Manual Figure 5.3 Schematic Diagram for IF System Receiving Audio Signal Processing: The audio processing circuit of receiver consists of IC300 and the peripheral circuit. Voice signals from IC200 are sent to IC301 ( CTCSS signaling filter circuit ) and IC300-D respectively after amplified in IC300-C.
PT500-2 Service Manual Squelch Circuit Part of the AF signal from the IC200 enters the FM IC again,and the noise component is amplified and rectified by a filter and an amplifier to produce a DC voltage corresponding to the noise level.
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PT500-2 Service Manual Figure 5.5 Schematic Diagram for Power Amplifier and Antenna Switch The modulated RF signals from VCO are amplified by Q101, Q102 and Q105 before the power amplification in Q107. Gate bias of Q105 and Q107 is controlled by APC circuit, so the output power of transmitter can be controlled conveniently by changing the gate bias voltage.
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MIC, but the internal PTT is still effective. 5.4 PLL Frequency Synthesizer Figure 5.8 Schematic Diagram for Frequency Synthesizer The PT500-2 adopts PLL frequency synthesizer. Frequency synthesizer consists of reference oscillator, voltage controlled oscillator (VCO), programmable frequency divider (PFD), phase comparator and low pass filter (LPF).
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PT500-2 Service Manual The oscillation frequency of VCO is compared with reference frequency to produce error signal after divided by PFD in IC1. The error signal is filtered by low pass filter before changing the VCO frequency to the set value in VCO (it is locking).
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PT500-2 Service Manual 5.7 MCU Unit: 5.9 Schematic Diagram for MCU Unit MCU Unit controls the operation of every unit to realize all functions of the PT500-2 Communication with external PC State data access Control PLL for the generation, receiving and transmitting of local oscillation frequency...
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PT500-2 Service Manual CTCSS/DCS signal coding and decoding: CTCSS/DCS signals from MCU (pin22 and pin18 output) are sent to VCO and TCXO for modulation respectively after filtering by R500 R501 C500 C501 and R504 R503 C920 C921. CTCSS/DCS signals from receiver are sent to MCU(pin52) for decoding, and then MCU test if there are CTCSS/DCS signals with the same setting of the station to decide whether open the speaker or not.
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PT500-2 Service Manual Frequency Frequency Frequency Frequency [Hz] [Hz] [Hz] [Hz] 67.0 94.8 131.8 186.2 69.3 97.4 136.5 192.8 71.9 100.0 141.3 203.5 74.4 103.5 146.2 210.7 77.0 107.2 151.4 218.1 79.7 110.9 156.7 225.7 82.5 114.8 162.2 233.6 85.4 118.8...
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PT500-2 Service Manual Table 5.2 DCS Coding Schedule 5.8 Description of Semiconductor Devices The distribution of each pin goes as the table 5.3. Table 5.3---Definition of CPU Base Pin:...
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PT500-2 Service Manual Active Pin No. Port Name Function Level Name APCSW APC switch PTT switch input Connect this pin to VCC via a 4.7K MODE resistor(*Burn) SIDE KEY1 input SIDE KEY2 input RESET CUP reset (*Burn) XOUT MCU clock...
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PT500-2 Service Manual GLED Green LED RLED Red LED TDIN TRFI TONE data input Alarm switch control(H:Controlled by ALARMC Volume Switch L:Emergency siren maximum volume) DEV2 Voice deviation adjustment 2 DEV1 Voice deviation adjustment 1 NARROW 12.5KHz MIDDLE 20KHz TXD1...
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PT500-2 Service Manual BUSY Busy level input TOPKEY TOPKEY input RXMUTE RX audio mute RSSI Received Signal Strength Indicator input PCTV APC/BPF control output AVSS DTMF DTMF/Beep output VREF AVCC RX_W/N RX Wide/Narrow switch Table 5.4 Functional description of semiconductor device...
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Chapter 7 PT500-2 Service Manual ADJUSTMENT 7.1 Required Test Equipment Table 7.1 Number Name Parameter requirements Above P2, compatible IBM PC, WINDOWS Computer 98/ME/2000/XPOperating System Programming PT500 Programming software software Programming Special Serial/USB (CPL-01) programming cable cable Output voltage:7.5V, output electric current:≥ 5A DC regulator Test range: 0.5---10W...
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Audio Frequency Test range: 10mV~10V voltmeter Recommend how to use: item 6, 7, 8, 10, 11 and 12 which listed in the table can be substituted by integrated tester HP8920/HP8921.
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PT500-2 Service Manual Figure 7.1 External Speaker/microphone Interface Definition 7.2 Adjustment Items Some detection and adjustment shall be made to the station technical data after changing the components during the maintenance. The debugging introduction of some related circuits goes as follows: Some parameters of the product can be adjusted by use of PT500 Programming Software of our company.
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PT500-2 Service Manual Steps for adjustment: 1) Enter Computer Test Mode by selecting “Test Mode” in main menu of PT500 Programming Software. 2) Select the items to be adjusted in choice menus, and then adjust the parameters by function keys on the computer keyboard. 3) Exit Computer Test Mode after adjustment.
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PT500-2 Service Manual 3.9kHz---4.5kHz (wideband) 3.2kHz--3.9kHz (median band) between 1.8kHz-- -2.3kHz (narrowband) (2/5)TONE, DTMF, MSK Deviation Adjust TONE, DTMF, MSK deviation in the computer adjustment mode. 3.2---4.0 kHz (wideband) 3.0kHz---3.6kHz (median band) 1.8---2.3kHz (narrowband) VOX1, VOX10 Adjust VOX1, VOX10 microphone sensitivity in the computer adjustment mode.
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RSSI(-120dBm), RSSI(-70dBm) The signal level output is set to -120dBm or -70dBm. Automatically records the corresponding RSSI level. Note: Voltage for the aforesaid tests: 7.5V +/-0.1V in room temperature Chapter 8 PT500-2 BOM No. TP-PT5002 PT500-2 PARTS LIST Component Name/Specificatio Parts No.
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PT500-2 Service Manual 702PT5002001 PT500-2 UNIT PT500-2 portable 701PT5002001 twoway radio PT500-2 packaging 605PT5000201 71200CT02001 CT-02 radio ring 70700CP02001 CP-02 rapid charger PT500U1 ANTENNA CRAK435001010 7100500240471 (about 160mm) 400-470MHz Power Supply(DC 709CA02US001 CA-02 12V 500mA) Lithium-ion Battery 70600CB05001 CB-05 1300mAH 7.4V...
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PT500-2 Service Manual STRUCTURE 2010PT500001A PT500 radio front cabinet black 2010CU600002A CU600 PTT plastic key black PC+ABS 2950 CU600 ear phone plastic plug black PC+ABS 2010CU600003A 2950 2010CU600004A CU600 ear phone cabinet PC+ABS 2950 2010CU600005A CU600 radio top cover black PC+ABS 2950...
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PT500-2 Service Manual 2040CU600002A CU600 PTT metal dome plate Φ33mm air filter nylon weave 306003301001A 7mm mic air filter Φ7.0X4.5X0.2 2040CU600004A 304060250001A encoder screw M7X0.75 special shape brass 304070250001A volume screw M6X0.75 special shape brass machine screw M2.0X4.0 PB(+) Ni-plate nylok...
PT500-2 Service Manual 0.2s ON Standby/battery 4.5s OFF not installed charging Charging completed Error 0.2s ON 0.2s OFF Chapter 10 Block and Schematic...
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PT500- DIAGRAM 2 BLOCK Title VER 1.0 Date:Size A3 Number Sheet of Revision File: Drawn By:...
PT500-2 Service Manual 16 个 Number of channels Channel separation W:25 kHz /M:20KHz/N:12.5kHz -30℃ ℃~ +60 Working temperature 50Ω Antenna Impedance Frequency Stability ±2.5ppm Battery (Standard Lithium-ion Battery: 1300mAh 7.4V Configuration) Dimension (W×L×H) 97.5 mm ×53.5 mm×31 mm Weight 230g (With battery and antenna) 7.2 Receiving part...
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PT500-2 Service Manual Battery pack may not be installed properly. Remove the The radio cannot be switched on or battery pack and install it again. no display after Battery power may be insufficient. Recharge or replace switched on.
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