Kenwood-TK-780-Service-Manual电路原理图.pdf

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1、 2001-5 PRINTED IN JAPANB51-8581-00 (N)1370VHF FM TRANSCEIVERTK-780/HSERVICE MANUALGENERAL . 2OPERATING FEATURES . 3REALIGNMENT. 15INSTALLATION. 20CIRCUIT DESCRIPTION. 28SEMICONDUCTOR DATA . 33DESCRIPTION OF COMPONENTS . 35PARTS LIST. 37EXPLODED VIEW . 47PACKING . 48ADJUSTMENT . 49PC BOARD VIEWSPLL/

2、VCO (X58-4540-11) : K2,HK2 . 57PLL/VCO (X58-4712-70) : K,HK . 58TX-RX UNIT (X57-6480-XX) (A/2) . 59TX-RX UNIT (X57-6480-XX) (B/2). 65SCHEMATIC DIAGRAM . 69BLOCK DIAGRAM. 77LEVEL DIAGRAM. 80TERMINAL FUNCTION . 82SPECIFICATIONS. 83CONTENTSMicrophone(T91-0621-05)Cabinet (Top)(A01-2165-13)Panel assy(A62

3、-0991-03)Key top(K29-5284-02)SUPPLEMENTThis service manual applied to products with 30200001 or subsequent serial numbers.In terms of the products with the serial numbers earier than 30200001, refer to the TK-780/Hservice manual as per part No. B51-8461-10.2TK-780/HGENERALINTRODUCTIONSCOPE OF THIS M

4、ANUALThis manual is intended for use by experienced techni-cians familiar with similar types of commercial grade com-munications equipment. It contains all required service infor-mation for the equipment and is current as of this publica-tion date. Changes which may occur after publication arecovere

5、d by either Service Bulletins or Manual Revisions,which are issued as required.ORDERING REPLACEMENT PARTSWhen ordering replacement parts or equipment informa-tion, the full part identification number should be included.This applies to all parts : components, kits, and chassis. Ifthe part number is n

6、ot known, include the chassis or kitnumber of which it is a part and a sufficient description ofthe required component, for proper identification.PERSONNEL SAFETYThe following precautions are recommended for person-nel safety : DO NOT transmit if someone is within two feet (0.6meter) of the antenna.

7、 DO NOT transmit until all RF connectors are secure andany open connectors are properly terminated. SHUT OFF this equipment when near electrical blastingcaps or while in an explosive atmosphere. All equipment should be properly grounded beforepower-up for safe operation. This equipment should be ser

8、viced by only qualified tech-nicians.PRE-INSTALLATION CONSIDERNATIONS1. UNPACKINGUnpack the radio from its shipping container and checkfor accessory items. If any item is missing, please contactKENWOOD immediately.2. LICENSING REQUIREMENTSFederal regulations require a station license for each ra-dio

9、 installation (mobile or base) be obtained by the equip-ment owner. The licensee is responsible for ensuring trans-mitter power, frequency, and deviation are within the limitspermitted by the station license.Transmitter adjustments may be performed only by a li-censed technician holding an FCC first

10、, second or generalclass commercial radiotelephone operators license. Thereis no license required to install or operate the radio.3. PRE-INSTALLATION CHECKOUT3-1. IntroductionEach radio is adjusted and tested before shipment. How-ever, it is recommended that receiver and transmitter opera-tion be ch

11、ecked for proper operation before installation.3-2. TestingThe radio should be tested complete with all cabling andaccessories as they will be connected in the final installa-tion. Transmitter frequency, deviation, and power outputshould be checked, as should receiver sensitivity, squelchoperation,

12、and audio output. QT equipment operationshould be verified.4. PLANNING THE INSTALLATION4-1. GeneralInspect the vehicle and determine how and where theradio antenna and accessories will be mounted.Plan cable runs for protection against pinching or crush-ing wiring, and radio installation to prevent o

13、verheating.4-2. AntennaThe favored location for an antenna is in the center of alarge, flat conductive area, usually at the roof center. Thetrunk lid is preferred, bond the trunk lid and vehicle chassisusing ground straps to ensure the lid is at chassis ground.4-3. RadioThe universal mount bracket a

14、llows the radio to bemounted in a variety of ways. Be sure the mounting surfaceis adequate to support the radios weight. Allow sufficientspace around the radio for air cooling. Position the radioclose enough to the vehicle operator to permit easy accessto the controls when driving.4-4. DC Power and

15、wiring1. This radio may be installed in negative ground electricalsystems only. Reverse polarity will cause the cable fuseto blow. Check the vehicle ground polarity before installa-tion to prevent wasted time and effort.2. You must connect the positive power lead directly tothe positive terminal of

16、the vehicle battery. Neverconnect the lead to any other positive power source,such as a cigarette lighter jack or fuse terminals.CAUTIONIf DC power is to be controlled by the vehicle ignitionswitch, a switching relay should be used to switch the posi-tive power lead. The vehicle ignition switch then

17、 controlsDC to the relay coil.3. You must also connect the ground lead directly tothe negative terminal of the vehicle battery.4. The cable provided with the radio is sufficient to handlethe maximum radio current demand. If the cable must beextended, be sure the additional wire is sufficient for the

18、current to be carried and length of the added lead.3TK-780/H5. INSTALLATION PLANNING CONTROL STATIONS5-1. Antenna systemControl station. The antenna system selection dependson many factors and is beyond the scope of this manual.Your KENWOOD dealer can help you select an antenna sys-tem that will bes

19、t serve your particular needs.5-2. Radio locationSelect a convenient location for your control station radiowhich is as close as practical to the antenna cable entrypoint. Secondly, use your systems power supply (whichsupplies the voltage and current required for your system).Make sure sufficient ai

20、r can flow around the radio and powersupply to allow adequate cooling.SERVICEThis radio is designed for easy servicing. Refer to theschematic diagrams, printed circuit board views, and align-ment procedures contained in this manual.NoteWhen you modify your radio as described in system set-up, take t

21、he following precaution.The rating of pin 7 (SB) of the accessory connector cable(KCT-19) on the rear of the radio is 13.6V (1A). Insert a 1Afuse if you use the SB pin for external equipment.Accessory connectorcable (KCT-19)If you do not intend to use the 3.5-mm jack for the exter-nal speaker, fit t

22、he supplied speaker-jack cap (B09-0235-05)to stop dust and sand getting in.GENERAL / OPERATING FEATURESSpeaker-jack cap(B09-0235-05)1. Operation FeaturesThe TK-780/780H is a VHF FM radio designed to operatein both trunking format (LTR model) and conventional for-mat (Conventional model). The program

23、mable features aresummarized.Model Trunking format Trunking modeConventional format Conventional mode1-1. Trunking FormatThis format can handle up to 32 systems with up to 250groups in each system. The transceiver can be used in bothtrunked mode and conventional mode. Systems, groups,and their funct

24、ions are programmed.1-2. Conventional FormatThis format can handle up to 250 groups with 250 chan-nels in each group. The transceiver can be used only in con-ventional mode. Groups, channels, and their functions areprogrammed.2. Transceiver Controls and Indicators (Fig. 1)2-1. Front Panel ControlsAl

25、l the keys on the front panel are momentary-type pushbuttons. The functions of these keys are explained below. POWER keyTransceiver POWER key. When the power is switchedoff, all the parameters, such as the system and group intrunking format, and the group and channel in conventionalformat, are store

26、d in memory. When the power is switchedon again, the transceiver returns to the previous conditions. SYSTEM UP/DOWN key(Trunking format, programmable) GROUP UP/DOWN key(Conventional format, programmable) SCAN key (Programmable) MONITOR key (Programmable) A, B, C and D key (Programmable) VOLUME UP/DO

27、WN key (Programmable) BUSY/TX LEDThe BUSY indicator (Green LED) shows that the channelis in use. The TX indicator (Red LED) shows that you aretransmitting.13+7613154TK-780/H2-2. Programmable KeysThe FPU (KPG-49D) enables programmable keys to se-lect the following functions.a73 Conventional formatAUX

28、-A, AUX-B (Only when voice scrambler is not se-lected), Channel down, Channel up, DTMF ID (BOT), DTMFID (EOT), Display character, Emergency (Only foot key),Function, Group down, Group up, Home channel, Horn alert,Key lock, Memory (RCL/STO), Memory (RCL), Memory(STO), Monitor A, Monitor B, Monitor C,

29、 Monitor D, Opera-tor selectable tone, Public address, Redial, Scan, Scan del/add, Scrambler (Only when voice scrambler is selected),Talk around, Volume down, Volume up and None.a73 Trunking formatAuto tel, AUX-A, AUX-B (Only when voice scrambler isnot selected), DTMF ID (BOT), DTMF ID (EOT), Displa

30、y char-acter, Emergency (Only foot key), Function, Group down,Group up, Home group, Horn alert, Key lock, Memory (RCL/STO), Memory (RCL), Memory (STO), Monitor A, Monitor B,Monitor C, Monitor D, Public address, Redial, Scan, Scandel/add, Scan temporary delete, Scrambler (Only whenvoice scrambler is

31、selected), System down, System up, TELdisconnect, Volume down, Volume up and None.These functions the FPU programs to the function keysand described in the following sections. Auto TEL (Trunking format)Automatically connects available repeaters that are con-nected to telephone circuits when operatin

32、g as LTR system.The time allocated to search for available repeaters is 60seconds, after which connection failure occurs, a DTMFtone is output and the function terminates.If connection to an available circuit is made, only ID 253,EOT or hang-up time-out can terminate the function. AUX-AIf this key i

33、s pressed, “AUX” icon lights on the LCD andAUX port which is inside of the transceiver turns to the highlevel. If pressed again, the “AUX” icon goes off and theAUX ports turns to the lower level. AUX-BThis function can be programmed when the voice scram-bler board is not installed.If this key is pre

34、ssed, an underscore (“_”) appears at theextreme right of the LCD and AUX port which is inside of thetransceiver turns to the active level. If pressed again, theunderscore disappears and the AUX ports turns to thedeactive level. Channel up/down (Conventional format)When the key is pressed each time,

35、the channel numberto be selected is incremented/decremented and repeats ifheld for one second or longer. This key works as the voicescrambler code selector in the voice scrambler code selectmode.OPERATING FEATURES DTMF ID (BOT)In conventional mode, if you press this key, a predeter-mined DTMF ID (Be

36、gin of TX) will be sent automatically. DTMF ID (EOT)In conventional mode, if you press this key, a predeter-mined DTMF ID (End of TX) will be sent automatically. Display characterThis key switches the LCD display between the systemand group number in trunking format and the group andchannel name in

37、conventional format. EmergencyPressing this key for longer than the programmed “Emer-gency Key Delay Time” causes the transceiver to enter theemergency mode. The transceiver jumps to the pro-grammed “Emergency system and group in trunking formatand the group and channel in conventional format” andtr

38、ansmits for the programmed “Active Time”.The transceiver disables mic mute while transmitting.After finishing transmission, the transceiver receivers forthe programmed “Interval Time”. The transceiver mutesthe speaker while receiving. Following the above sequence,the transceiver continues to transmi

39、t and receive. FunctionPressing this key causes the transceiver to display“FCN”. Then, pressing a microphone DTMF key causes thecorresponding programmed function to start. This key maybe convenient when using many functions with the micro-phone 12-key keypad. Group up/downWhen the key is pressed eac

40、h time, the group number tobe selected is incremented/decremented and repeats if heldfor one second or longer. Home channel (Conventional format)Press this key once, the channel switches to the pre-pro-grammed home channel. Home group (Trunking format)Each pressing of the key selects a preset system

41、/group. Horn alertIf you are called from the base station using 2-tone/DTMFwhile you are away from your transceiver, you will bealerted by the vehicle horn or some other type of externalalert. To turn the horn alert function on , press this key. Aconfirmation tone sounds, and the display shows “HA”

42、onthe sub LCD.If this key is pressed again, the horn alert function isturned off. Key lockPressing this key causes the transceiver to accept entryof only the Function, Key lock, PTT, Monitor A, Moni-tor B, Monitor C, Monitor D, and Emergency keys.5TK-780/H Message modePress this key to enter the mes

43、sage mode. (See “Alpha-numeric Two-way Paging Function” for details) MemoryThis key allows DTMF memory data to be recalled; up to32 memories each with a memory dial of up to 16 digits andan A/N of up to 10 digits per memory. MonitorUsed to release signalling or squelch when operating as aconventiona

44、l. It is also used to reset option signalling. Operator selectable tone (Conventional format)This key switches the pre-set decode QT/DQT and en-code QT/DQT to OST (Operator Selectable Tone) tone pair.Press this key, the transceiver enters to OST selectmode. In this mode, the display shows “OFF” and

45、the op-erator can select one of the OST tone pair using the groupup/down key. The display shows “TONE*” and tonepair No. *is selected.Press OST key again, the transceiver exits from the OSTselect mode, and returns to the group/channel mode withthe handset indicator ( ). The handset indicator ( ) mea

46、nsthat the OST tone pair is selected. OST tone pair number orOFF can be memorized for each channel.16 kinds of tone pair for OST can be programmed byKPG-49D. OST is useful to access the repeater with sameradio frequency and different tone (QT/DQT). Public addressPublic address amplifies the microphone audio, and out-puts it through a PA speaker. PA is activated by pressingthis key. A confirmation tone sounds, and the display shows“PUBLIC ADRS”. PA can be activated at anytime (scanningor non-scanning).The RADIO continues to scan however, no RADIO