Codan_8525B_8528_serv.pdf

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1、HF SSB Transceiver 8525B/8528 series Technical Service Manual Volume 1 1989 Codan Pty Ltd. ACN 007 590 605 Order code 15-02036 Issue 6, November 1995 Head Office Codan Pty Ltd ACN 007 590 605 81 Graves Street Newton South Australia 5074 International +61 8 8305 0311 Facsimile+61 8 8305 0411 Marketin

2、g Offices Codan (U.K.) Ltd Gostrey House Union Road Farnham, Surrey GU9 7PT United Kingdom International +44 1252 717 272 Facsimile+44 1252 717 337 Telex858355 Codan Pty Ltd Suite 11A, 2 Hardy Street South Perth Western Australia 6151 International +61 8 9368 5282 Facsimile+61 8 9368 5283 Publicatio

3、n No: 15-02036Issue 6 Table of Contents 1 General Information 1.1Introduction.1-1 1.2Specifications.1-2 1.2.1General.1-2 1.2.2Receiver.1-4 1.2.3Transmitter.1-6 1.2.4Rear Panel Connectors.1-7 1.2.5Front Panel Connector.1-10 1.3Options and Accessories .1-11 1.3.1Options.1-11 1.3.2Accessories.1-12 1.4A

4、bbreviations.1-13 1.5Circuit Reference Designations.1-20 1.6Units.1-21 1.7Unit Multipliers.1-21 2 Block Diagram 3 Brief Description 3.1General .3-1 3.2Receive.3-1 3.3Transmit .3-2 3.4Synthesizers.3-2 3.5Display, Control and Switching .3-3 3.6External Power Amplifiers.3-3 ii Table of Contents8525B/85

5、28 Technical Service Manual Issue 6Publication No: 15-02036 4 Technical Description 4.1Control and Supply Voltages.4-1 4.1.1Supply Voltages .4-1 4.1.2Power and Control Lines.4-2 4.1.3Overvoltage and Reverse Voltage Protection.4-2 4.1.4Transceiver Power On/Off .4-2 4.1 5High Power Transceiver Protect

6、ion and Power On/Off.4-3 4.2Receiver.4-4 4.2.1Input Filters .4-4 4.2.2Mixers, First IF Amplifiers and Filters .4-4 4.2.3Noise Blanker.4-5 4.2.4IF Crystal Filter and Amplifier.4-5 4.2.5Demodulator.4-5 4.2.6Audio Mute .4-6 4.2.7Volume Control and Audio Amplifier.4-6 4.3Transmitter Exciter.4-7 4.3.1Mic

7、rophone Amplifier.4-7 4.3.2Modulator.4-7 4.3.3Crystal Filter.4-8 4.3.4Mixers, IF Filters and IF Amplifier.4-8 4.4Local Oscillators.4-9 4.4.1Voltage Controlled Oscillators (VCO).4-9 4.4.2Phase/Frequency Detectors and Dividers.4-9 4.4.3Lock Signals.4-10 4.4.4Loading of Frequency Data to Synthesizers.4

8、-10 4.4.51650/1647kHz Local Oscillators.4-11 4.4.6Clarifier .4-11 8525B/8528 Technical Service ManualTable of Contents iii Publication No: 15-02036Issue 6 4.5Microprocessor Controller PCB (04-02451 8528 series including 8528S and H versions. (H transmission specifications included in a separate Tech

9、nical Service Manual (code 2037), covering the 4402 and 4404 PA units). Frequency RangeTransmit: 2 to 24MHz Receive: 0.25 to 30MHz Frequency Generation All frequencies generated by synthesizer. Channel Capacity8525B: 99 single or two-frequency simplex channels with 10Hz resolution controlled by plug

10、-in EPROM 8528: single or two-frequency simplex channels with 10Hz resolution controlled by plug-in EPROM and 99 EEPROM controlled channels with 100Hz resolution.The total number of channels will depend on the version of 8528 series to a maximum of 600. Receive frequencies of the EEPROM controlled c

11、hannels can be entered from the front panel by the operator. Transmit frequencies of the EEPROM controlled channels can be entered from the front panel by qualified technical personnel or (where authorised) by the operator. Operating ModesLand: Single sideband (J3E) USB, with LSB (Option L) or switc

12、hed sideband (Option LU) available as options. Marine: Single sideband (J3E) USB. LSB may be programmed for specific frequencies (requires Option L). On 2182kHz J3E or H3E USB selectable. Frequency Stability USB: 2(3)ppm 30C to +60C LSB: 2(3)ppm 20Hz 30C to +60C Long term ageing1ppm per year. 8525B/

13、8528 Technical Service ManualGeneral Information 1-3 Publication No: 15-02036Issue 6 Oven warm-up time 1 minute. ControlsSealed membrane switches. IndicatorsRefer to illustrations for details. 8525B: All indicators except Tx automatically dimmed for low ambient light levels. 8528: All indicators exc

14、ept Tx may be manually dimmed by front panel controls if required. Transmit/Receive Switching Approximately 20ms using the Option PS connection. Transmit/receive frequencies may be separated by up to 1MHz. ConnectorsRFUHF connector Extended/Local control (Option R) required for Control Head operatio

15、n or remote control. Antenna control Extension Loudspeaker External Selective Call (Option PS) External Alarm (for Options SDE and SDEM) and/or unswitched battery for remote control (Option PP) Note: Options PS and PP are mutually exclusive. RF Input/Output Impedance 50 ohms nominal. Supply Voltage1

16、2V DC nominal, negative earth. Normal operating range 10.5 to 15V DC. Maximum operating range 9 to 16V DC. Overvoltage Protection Shutdown at 16V DC (nominal) for duration of overvoltage. Supply Current8525B: Receive, no signal 400550mA 8528: Receive, no signal, display illumination on: 400mA; off:

17、340mA Transmit: see section 1.2.3 EnvironmentalAmbient Temperature Relative Humidity 30C to +30C95% +30C to +60Cfrom 95% at +30C to 30% at +60C Derate upper ambient temperature by 1C per 330m above sea level. 1-4 General Information8525B/8528 Technical Service Manual Issue 6Publication No: 15-02036

18、CoolingConvection or fan (Option F). Size and weightTransceiver only: 250mm W x 78mm H x 350mm D; 3.41kg With mounting cradle: 270mm W x 90mm H x 350mm D; 3.92kg 8530 Control Head: 180mm W x 65mm H x 70mm D With mounting bracket: 190mm W x 78mm H x 70mm D; 700g 8531 Control Head: 248mm W x 78mm H x

19、70mm D With mounting bracket: 252mm W x 92mm H x 70mm D; 900g Note: Depth measurements (D) include rear connectors/cables. FinishCase: Silver-grey Panel surround and heat sink: Matt black Panel overlay: LexanMatt black Painted surfaces are scratch-resistant textured polyester powdercoat. 1.2.2Receiv

20、er TypeDual conversion superheterodyne. IF Frequencies45MHz, 1650kHz. Sensitivity0.25 to 0.5MHz: 0.5 to 2MHz: 2 to 28MHz: 28 to 30MHz: Not specified Approximately 8V PD 0.25(0.35)V PD 119( 116)dBm for 10dB SINAD with greater than 50mW audio output. 0.5V PD Input ProtectionWill withstand 50V rms RF f

21、rom a 50 source. SelectivityGreater than 70(65)dB at 1kHz and +4.2kHz ref SCF USB. Pass band 6(8)dB 300 2800Hz. Ripple 1.5(3)dB pp 500 2500Hz. 8525B/8528 Technical Service ManualGeneral Information 1-5 Publication No: 15-02036Issue 6 Desensitisation10dB SINAD reduced to 7dB SINAD. 1 and +4.4kHz ref

22、SCF (USB) 62(55)dB. 10kHz 85(80)dB. 50kHz 100(95)dB. Image RejectionBetter than 90(80)dB Spurious Responses Better than 90(70)dB. Self generated signals 0.25V PD; 6.6MHz, 9.998MHz, 13.2MHz, 19.8MHz, 26.4MHz. Cross ModulationA signal 90(85)dB above a signal producing 10dB SINAD, modulated 30% and rem

23、oved at least 20kHz from the wanted signal will produce an increase in receiver noise of less than 3dB. BlockingAs for desensitisation. IntermodulationTo produce a third order intermodulation product equivalent to a wanted signal producing 10dB SINAD, two unwanted signals greater than 30kHz removed

24、from the wanted signal must have a level greater than 85(80)dB above the wanted signal. Third order intercept +10(7)dBm, not affected by AGC. AGCLess than 6dB variation in output level for input variations between 1.5(2.5)V and 100mV PD. Fast attack, slow release. AF Response1 typ(3)dB 300 to 2800Hz

25、. AF Power and Distortion 2.5W into 8 ohms: 5% THD 5W into 4 ohms: 5% THD 8W into 2 ohms: 5% THD ClarifierLand: Nominal 0.001% Marine: 180Hz Clarifier is automatically reset to mid-range with channel change. Inband IMDBetter than 25dB IMD with two 50mV PD RF inputs. Signal to noise vs Input Level 5V

26、 PD: 34dB S/N 50V PD: 53dB S/N 500V PD: 60dB S/N 1-6 General Information8525B/8528 Technical Service Manual Issue 6Publication No: 15-02036 1.2.3 Transmitter Power Output Land 100W PEP at 2MHz falling linearly with frequency to 90W PEP at 24MHz 0.5dB. Marine125W PEP at 2MHz falling linearly with fre

27、quency to 90W PEP at 24MHz 1dB. CW or single tone: approximately 60% of PEP with average PEP control. Duty Cycle100% normal speech over full temperature range. 100% ARQ up to 30C. 25% continuous data mode (5 minutes on maximum) at ambient temperature up to 30C. 100% all modes up to maximum ambient o

28、f 45C with Option F. Supply CurrentOutput power 100/125W 2-tone or CW: 9 to 12A Average speech: 6A for battery life calculations. ProtectionSafe under all load conditions by limiting reflected power to 6W and limiting PA transistor collector voltage swing. Thermal protection against excessive heatsi

29、nk temperature. AF ResponseOverall response of microphone and transmitter rises approximately 6dB/octave 300 2800Hz. Electrical input 6(8)dB, 300 2800Hz. Ripple 1.5(3)dB pp, 500 2500Hz. Spurious for these, the EMF is twice the attenuator scale reading. Figure 1.1 EMF Verses PD 1-20 General Informati

30、on8525B/8528 Technical Service Manual Issue 6Publication No: 15-02036 1.5Circuit Reference Designations AAssembly BTransducerMicrophone, Loudspeaker, etc CCapacitor DDiodesmall signal and power EHeating device FProtection deviceFuse, etc GGeneratorbattery, etc HSignalling/indicating deviceLamp. LED,

31、 Buzzer, etc ICIntegrated Circuit, thick film hybrid JJack socket KRelay, key switch LInductor MIndicating devicemeter, etc PPlug RResistor SSwitch TTransformer, common mode choke TPTest Point UModem, Modulator VSemiconductor (not including small signal and power diodes) XTerminals ZQuartz Crystal,

32、Crystal Filter, Frequency Network 8525B/8528 Technical Service ManualGeneral Information 1-21 Publication No: 15-02036Issue 6 1.6Units AAmperemmetre CCelsius (degrees)minminute CCoulombNNewton FFaradPaPascal ggramSSiemen hhourssecond HHenryTTesla HzHertzVVolt JJouleWWatt KKelvin (degrees)WbWeber lli

33、treOhms 1.7Unit Multipliers Tteraone million million10l2 Ggigaone thousand million109 Mmegaone million106 kkiloone thousand103 hhectoone hundred102 dadecaten10 ddecione tenth10-1 ccentione hundredth10-2 mmillione thousandth10-3 microone millionth10-6 nnanoone thousand millionth10-9 ppicoone million

34、millionth10-12 n 1-22 General Information8525B/8528 Technical Service Manual Issue 6Publication No: 15-02036 8525B/8528 Technical Service Manual3-1 Publication No: 15-02036Issue 6 3Brief Description 3.1General This description should be read in conjunction with Block Diagram 03-00636. The same frequ

35、ency conversions are used in both transmit and receive modes, therefore many circuits are common to both modes of operation. Signal routing is determined by switching and control voltages according to the mode selected. 3.2Receive The RF signal from the antenna passes through the PA low-pass filters

36、, then via the transmit/receive relay and broadcast filter on the PA PCB, to the switched high-pass filters on the RF, Mixer, and Dual Synthesizer PCB. Filters are automatically selected according to the frequency band in use. The band-pass filtered signal is applied to the first mixer. This double-

37、 balanced, diode-ring mixer, driven from VCO1, converts the signal up to a 45MHz IF signal. The 45MHz signal is amplified and filtered with a 20kHz wide roofing filter. The output of this filter is mixed with the output of VCO2 in another double-balanced, diode-ring mixer. This produces a second IF

38、of 1650kHz. The second IF signal is passed to the IF amplifier and noise limiter. The noise limiter is designed to suppress impulse noises such as motor vehicle ignition noise. The limiter operates by gating the IF signal path for the duration of the noise pulses. The crystal filter on the Audio and 1650kHz IF PCB reduces the bandwidth to 2.5kHz b