Kenwood_TK-780_H_serv.pdf

2001-5 PRINTED IN JAPAN B51-8581-00 (N) 1370 VHF FM TRANSCEIVER TK-780/H SERVICE MANUAL GENERAL . 2 OPERATING FEATURES . 3 REALIGNMENT. 15 INSTALLATION. 20 CIRCUIT DESCRIPTION. 28 SEMICONDUCTOR DATA. 33 DESCRIPTION OF COMPONENTS. 35 PARTS LIST. 37 EXPLODED VIEW . 47 PACKING . 48 ADJUSTMENT . 49 PC BOARD VIEWS PLL/VCO (X58-4540-11) : K2,HK2 . 57 PLL/VCO (X58-4712-70) : K,HK. 58 TX-RX UNIT (X57-6480-XX) (A/2) . 59 TX-RX UNIT (X57-6480-XX) (B/2). 65 SCHEMATIC DIAGRAM . 69 BLOCK DIAGRAM. 77 LEVEL DIAGRAM. 80 TERMINAL FUNCTION . 82 SPECIFICATIONS. 83 CONTENTS Microphone (T91-0621-05) Cabinet (Top) (A01-2165-13) Panel assy (A62-0991-03) Key top (K29-5284-02) SUPPLEMENT This 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/H service manual as per part No. B51-8461-10. 2 TK-780/H GENERAL INTRODUCTION SCOPE OF THIS MANUAL This 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 are covered by either Service Bulletins or Manual Revisions, which are issued as required. ORDERING REPLACEMENT PARTS When ordering replacement parts or equipment informa- tion, the full part identification number should be included. This applies to all parts : components, kits, and chassis. If the part number is not known, include the chassis or kit number of which it is a part and a sufficient description of the required component, for proper identification. PERSONNEL SAFETY The following precautions are recommended for person- nel safety : DO NOT transmit if someone is within two feet (0.6 meter) of the antenna. DO NOT transmit until all RF connectors are secure and any open connectors are properly terminated. SHUT OFF this equipment when near electrical blasting caps or while in an explosive atmosphere. All equipment should be properly grounded before power-up for safe operation. This equipment should be serviced by only qualified tech- nicians. PRE-INSTALLATION CONSIDERNATIONS 1. UNPACKING Unpack the radio from its shipping container and check for accessory items. If any item is missing, please contact KENWOOD immediately. 2. LICENSING REQUIREMENTS Federal regulations require a station license for each ra- dio 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 limits permitted by the station license. Transmitter adjustments may be performed only by a li- censed technician holding an FCC first, second or general class commercial radiotelephone operators license. There is no license required to install or operate the radio. 3. PRE-INSTALLATION CHECKOUT 3-1. Introduction Each radio is adjusted and tested before shipment. How- ever, it is recommended that receiver and transmitter opera- tion be checked for proper operation before installation. 3-2. Testing The radio should be tested complete with all cabling and accessories as they will be connected in the final installa- tion. Transmitter frequency, deviation, and power output should be checked, as should receiver sensitivity, squelch operation, and audio output. QT equipment operation should be verified. 4. PLANNING THE INSTALLATION 4-1. General Inspect the vehicle and determine how and where the radio antenna and accessories will be mounted. Plan cable runs for protection against pinching or crush- ing wiring, and radio installation to prevent overheating. 4-2. Antenna The favored location for an antenna is in the center of a large, flat conductive area, usually at the roof center. The trunk lid is preferred, bond the trunk lid and vehicle chassis using ground straps to ensure the lid is at chassis ground. 4-3. Radio The universal mount bracket allows the radio to be mounted in a variety of ways. Be sure the mounting surface is adequate to support the radios weight. Allow sufficient space around the radio for air cooling. Position the radio close enough to the vehicle operator to permit easy access to the controls when driving. 4-4. DC Power and wiring 1. This radio may be installed in negative ground electrical systems only. Reverse polarity will cause the cable fuse to blow. Check the vehicle ground polarity before installa- tion to prevent wasted time and effort. 2. You must connect the positive power lead directly to the positive terminal of the vehicle battery. Never connect the lead to any other positive power source, such as a cigarette lighter jack or fuse terminals. CAUTION If DC power is to be controlled by the vehicle ignition switch, a switching relay should be used to switch the posi- tive power lead. The vehicle ignition switch then controls DC to the relay coil. 3. You must also connect the ground lead directly to the negative terminal of the vehicle battery. 4. The cable provided with the radio is sufficient to handle the maximum radio current demand. If the cable must be extended, be sure the additional wire is sufficient for the current to be carried and length of the added lead. 3 TK-780/H 5. INSTALLATION PLANNING CONTROL STATIONS 5-1. Antenna system Control station. The antenna system selection depends on many factors and is beyond the scope of this manual. Your KENWOOD dealer can help you select an antenna sys- tem that will best serve your particular needs. 5-2. Radio location Select a convenient location for your control station radio which is as close as practical to the antenna cable entry point. Secondly, use your systems power supply (which supplies the voltage and current required for your system). Make sure sufficient air can flow around the radio and power supply to allow adequate cooling. SERVICE This radio is designed for easy servicing. Refer to the schematic diagrams, printed circuit board views, and align- ment procedures contained in this manual. Note When you modify your radio as described in system set- up, take the 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 1A fuse if you use the SB pin for external equipment. Accessory connector cable (KCT-19) If you do not intend to use the 3.5-mm jack for the exter- nal speaker, fit the supplied speaker-jack cap (B09-0235-05) to stop dust and sand getting in. GENERAL / OPERATING FEATURES Speaker-jack cap (B09-0235-05) 1.Operation Features The TK-780/780H is a VHF FM radio designed to operate in both trunking format (LTR model) and conventional for- mat (Conventional model). The programmable features are summarized. ModelTrunking formatTrunking mode Conventional formatConventional mode 1-1. Trunking Format This format can handle up to 32 systems with up to 250 groups in each system. The transceiver can be used in both trunked mode and conventional mode. Systems, groups, and their functions are programmed. 1-2. Conventional Format This 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 are programmed. 2. Transceiver Controls and Indicators (Fig. 1) 2-1. Front Panel Controls All the keys on the front panel are momentary-type push buttons. The functions of these keys are explained below. POWER key Transceiver POWER key. When the power is switched off, all the parameters, such as the system and group in trunking format, and the group and channel in conventional format, are stored in memory. When the power is switched on 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/DOWN key (Programmable) BUSY/TX LED The BUSY indicator (Green LED) shows that the channel is in use. The TX indicator (Red LED) shows that you are transmitting. 1 3 + 7 6 13 15 4 TK-780/H 2-2. Programmable Keys The FPU (KPG-49D) enables programmable keys to se- lect the following functions. Conventional format AUX-A, AUX-B (Only when voice scrambler is not se- lected), Channel down, Channel up, DTMF ID (BOT), DTMF ID (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, 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. Trunking format Auto tel, AUX-A, AUX-B (Only when voice scrambler is not selected), DTMF ID (BOT), DTMF ID (EOT), Display 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, Scan del/add, Scan temporary delete, Scrambler (Only when voice scrambler is selected), System down, System up, TEL disconnect, Volume down, Volume up and None. These functions the FPU programs to the function keys and described in the following sections. Auto TEL (Trunking format) Automatically connects available repeaters that are con- nected to telephone circuits when operating as LTR system. The time allocated to search for available repeaters is 60 seconds, after which connection failure occurs, a DTMF tone 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-A If this key is pressed, “AUX” icon lights on the LCD and AUX port which is inside of the transceiver turns to the high level. If pressed again, the “AUX” icon goes off and the AUX ports turns to the lower level. AUX-B This function can be programmed when the voice scram- bler board is not installed. If this key is pressed, an underscore (“_”) appears at the extreme right of the LCD and AUX port which is inside of the transceiver turns to the active level. If pressed again, the underscore disappears and the AUX ports turns to the deactive level. Channel up/down (Conventional format) When the key is pressed each time, the channel number to be selected is incremented/decremented and repeats if held for one second or longer. This key works as the voice scrambler code selector in the voice scrambler code select mode. OPERATINGFEATURES DTMF ID (BOT) In conventional mode, if you press this key, a predeter- mined DTMF ID (Begin 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 character This key switches the LCD display between the system and group number in trunking format and the group and channel name in conventional format. Emergency Pressing this key for longer than the programmed “Emer- gency Key Delay Time” causes the transceiver to enter the emergency mode. The transceiver jumps to the pro- grammed “Emergency system and group in trunking format and the group and channel in conventional format” and transmits for the programmed “Active Time”. The transceiver disables mic mute while transmitting. After finishing transmission, the transceiver receivers for the programmed “Interval Time”. The transceiver mutes the speaker while receiving. Following the above sequence, the transceiver continues to transmit and receive. Function Pressing this key causes the transceiver to display “FCN”. Then, pressing a microphone DTMF key causes the corresponding programmed function to start. This key may be convenient when using many functions with the micro- phone 12-key keypad. Group up/down When the key is pressed each time, the group number to be selected is incremented/decremented and repeats if held for 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/group. Horn alert If you are called from the base station using 2-tone/DTMF while you are away from your transceiver, you will be alerted by the vehicle horn or some other type of external alert. To turn the horn alert function on , press this key. A confirmation tone sounds, and the display shows “HA” on the sub LCD. If this key is pressed again, the horn alert function is turned off. Key lock Pressing this key causes the transceiver to accept entry of only the Function, Key lock, PTT, Monitor A, Moni- tor B, Monitor C, Monitor D, and Emergency keys. 5 TK-780/H Message mode Press this key to enter the message mode. (See “Alpha- numeric Two-way Paging Function” for details) Memory This key allows DTMF memory data to be recalled; up to 32 memories each with a memory dial of up to 16 digits and an A/N of up to 10 digits per memory. Monitor Used to release signalling or squelch when operating as a conventional. 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 select mode. In this mode, the display shows “OFF” and the op- erator can select one of the OST tone pair using the group up/down key. The display shows “TONE*” and tone pair No. * is selected. Press OST key again, the transceiver exits from the OST select mode, and returns to the group/channel mode with the handset indicator (). The handset indicator ( ) means that the OST tone pair is selected. OST tone pair number or OFF can be memorized for each channel. 16 kinds of tone pair for OST can be programmed by KPG-49D. OST is useful to access the repeater with same radio frequency and different tone (QT/DQT). Public address Public address amplifies the microphone audio, and out- puts it through a PA speaker.