52-7880LC2B UHF DATA TRANSCEIVERS PLL SYNTHESIZED (EEPROM) Service Manual HE C HERMES ELECTRONICS CO., LTD.
TABLE OF CONTENS 1. SPECIFICATION …………………………………………………………………..2 2. CONNECTIONS 3. CIRCUIT AND OPERATION DESCRIPTION……………………3-4 DESCRIPTION ……………………………………………………..5-7 4. PERFORMANCE TEST AND ALIGNMENT……………………………8 5. TEST EQUIPMENT CONFIGURATION …………………………………9 6. TRANSMITTER PERFORMANCE TEST …………….……………………….10-12 7. PARTS LIST ……………………………………………………………………..13-16 8. PROGRAMMER INSTRUCTION……..……………………………………….17-21 9. PRINT CIRCUIT BOARD LAYOUT……………………………………………..22-24 10. PARTS ASSEMBLY ……….
PAGE1 1. SPECIFICATION GENERAL SPECIFICATIONS POWER SOURCE ……………………………………….13.80VD.C. TEMPERATURE RANGE STORAGE ……………………………………….80℃ maximum -40℃ min,25℃ nominal OPERATING …………………………………….70℃ maximum -20℃ min. ANTENNA IMPEDANCE ………………………………...50Ω FREQUENCIES OF OPERATION ………………………..406-430MHZ,450-470MHZ FREQUENCY TOLERANCE AND STABILITY …………±1.5PPM CHANNEL CAPABILITY ………………………………….1 NOMINAL DIMENSIONS ………………………………….107 ㎜(L)X 54 ㎜(W)X 32 ㎜(H) WEIGHT ……………………………………………………….
EXTERNAL CONNECTIONS 1. - 50Ω BNC SOCKET 2. - 9 WAY 〝 D 〞TYPE PLUG(J2) 2. CONNECTIONS D-TYPE PIN J2-1 J2-2 J2-3 J2-4 J2-5 J2-6 J2-7 J2-8 J2-9 AND OPERATION INTERCONNECTIONS FUNCTION DATA_IN DATA_OUT PTT GND B+ CDS NC PGM_DATA PGM_ENB TYPE ANALOGUE ANALOGUE INPUT GND V+ OUTPUT RANGE 106mV 250~350mV 0V/+5V 0V +13.
U4(52-7880LC2) CONNECTIONS CONNECTIONS PIN FUNCTION TYPE JP1-1 DATA_IN ANALOGUE JP1-2 DATA_OUT ANALOGUE JP1-3 PTT INPUT JP1-4 GND GND JP1-5 B+ V+ JP1-6 CDS OUTPUT JP1-7 PGM_ENB INPUT JP1-8 PGM_DATA INPUT JP1-9 AND RANGE 106mV 250~350mV 0V/+3.3V 0V +6.0V OPEN/SHORT 0V/3.
3. CIRCUIT DESCRIPTION TRANSMITTER The transmitter is comprised of: • Audio frequency connections from JP1 pin 1 • Frequency Synthesizer • Transmitter Audio frequency connections In the TX path , audio signal can be send into the chip RDA1846 through AC coupling capacitors.
Transmitter The transmitter comprises: PA Buffer PA Module Amp ANTENNA RF LPF SWITCH Power Control Buffer When the radio is in transmit mode the U1 is generated RF signal pass to the buffer/pre-amplifier Q1 and Q2 associated components. PA module The Q2 output signal is passed to Q3 via a matching network consisting of Inductor L5 , L15 and C32 and C34. Q3 is power amplifier .
Receiver The receiver comprises: Antenna Switch In receive, the diode D4 are reverse biased. L212 is now in circuit, passing the signal from the antenna to the U1 LNA input. . In the RX path , the voice signal after demodulation is sent to the internal DAC which can directly drive a 32 ohm resistance loading through AC coupling. Carrier Detect A Carrier Detect ( MUTE DETECT ) output is available on pin 6 of JP1 . When noise is present, the voltage at pin 26 of U1 is LOW.
4. PERFORMANCE TEST AND ALIGNMENT The alignment and performance test procedures assume the use of the following equipment. Discrete test equipment Volt Meter RF Power Meter.
5. TEST EQUIPMENT CONFIGURATION. RF Signal Generator Watt Meter with 20dB Attenuator Audio Generator Modulation Meter SINAD Meter OSCILLOSCOPE RADIO VOLT Meter Spectrum Analyzer DC Power Supply Frequency Counter 123.
6. TRANSMITTER PERFORMANCE TESTS Power Output 1. Set the power supply voltage to 6.0V dc. and monitor the voltage during transmit. 2. Switch data radio TX and check and record the output power. The nominal output 3. power is adjustable between 2 to 3W . Set the PTT switch to OFF . Peak Deviation 1. Connect the oscilloscope to the output of the modulation meter. 2. 3.
Transmitter Alignment Automatic Power Adjustment Transmit periods longer than 3 minutes are to be avoided. 1. Switch to data radio to TX. 2. 3. make the transmit power between 2 to 3W. Switch the data radio to transmitter OFF. Frequency accuracy 1. Whilst transmitting, measure the transmit frequency using the RF frequency counter. 2. Adjust VR1 so that frequency is as close as possible to the exact required transmit frequency. Ideally it should be within 100 Hz at room temperature.
Modulation Deviation Adjustment 1. 2. Connect a power meter, modulation meter and oscilloscope to radio. The radio should be programmed to contain a channel with a frequency in the middle the band of interest with an RF power setting of 2 W. 3. 4. Switch the data radio ON. Inject a 106mVrms SINE wave signal at a frequency of 1000Hz into pin 1 of JP1, Set the data radio to TX Observe the oscilloscope display to check that the 1000Hz tone is a sine wave and set deviation is 3.5KHZ.
7.
U4(52-7880LC2) Revision: January 19, 2011 15:53:17 Bill Of Materials Item Quantity Reference Part _________________________________________________________________ 16 1 C58 6P 17 1 D1 RLS4148 18 2 D3,D4 RLS135 19 1 J1 BNC 20 1 JP1 PCB PLUG 8PIN/2.54mm 21 1 JP2 PCB PLUG 9PIN/2.54mm 22 1 L1 12NH/CHIP 23 2 L2,L13 27NH/CHIP 24 1 L3 6.
U4(52-7880LC2) Revision: January 19, 2011 15:53:17 Bill Of Materials Item Quantity Reference Part _________________________________________________________________ 26 2 L5,L15 5.6NH/CHIP 27 2 L7,L14 4.
U4(52-7880LC2) Revision: January 19, 2011 15:53:17 Bill Of Materials Item Quantity Reference Part _________________________________________________________________ 42 1 R28 470K 43 1 RP1 10K*4 SMT 44 1 U1 RDA1846 45 1 U2 ELM7S32 46 1 U3 PIC16F630/SOIC/SMT 47 1 U4 UTC UR132L-3.
8. PROGRAMMER INSTRUCTION Welcome to PC Programmer. Please Read this file, before you first use the software. TABLE OF CONTENTS 1. 2. 3. Brief introduction Before Installing Install PC Programmer 4. 5. INSTRUCTIONS UnInstall PC Programmer 1. Brief introduction Welcome to PC Programmer. This program is designed to be used with the Interface Adapter. The following equipment will be needed to program the Device: A.
4. INSTRUCTIONS 4.1 Connection 4.2 Start up PC Programmer 4.3 Edit Configuration 4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 Open/Recall/Upload Configuration file Edit Channel data Set Option item (Block)Cut/Copy/Delete/Paste Auto-Frequency edit 4.3.6 Save a Configuration to disk 4.3.7 Download Configuration to device 4.3.8 Print a Configuration 4.4 Exit PC Programmer 4.1 Connection 1.Connect one side of Interface Adapter to the computer's serial port.
4.2 Start up PC Programmer 1.Select 'Start', choose 'Programs', click on the '*** Serial PC Programmer' program. 2.When HD Serial PC Programmer is started, a main form will be shown after a greeting form. 3.There has a menu bar at the top of the main form, and a message at the bottom. box NOTE:The program is menu driven for all pertinent commands. All the commands can be accessed by either key board or the left mouse button.
4.3.3 Edit Option item 1)To Edit Channel the Option View then Pop up the double click on Option, Select a particular channel number in Window by either the arrow key or click on it, input window for Channel Option, 'Enter' key or the selected channel number. 2)To Edit System Option, Pop up input window for System Option, click "SYSTEM" in the 'OPTION' menu. 3)To Edit Advanced Option, Pop up input window for Advanced Option, click "ADVANCED OPTION" in the 'OPTION' menu.
4)Click 'OK' button on the input window to accept the change or 'CANCEL' to not change, and return back to Configuration Window. 4.3.6 Save a Configuration to disk 1)Different configuration can be saved to disk. 2)Click on 'SAVE' item in 'FILE' Menu will overwrite an existing configuration file on your disk by current configuration. 3)Select 'SAVE AS' from 'FILE' Menu will save the current configuration by a name as you prefer. 4.3.
Federal Communication Commission Interference Statement This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
