Kenwood TK-780 Service Manual Supplement

Also see for TK-780 series: Programming instructions Instruction manual Service manual Instruction manual Service manual

2TK-780/H GENERALINTRODUCTIONSCOPE OF THIS MANUALThis 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 arecovered 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 not 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.• 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 serviced 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 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, second or generalclass commercial radiotelephone operator’s 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 checked 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, 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 overheating.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 allows the radio to bemounted in a variety of ways. Be sure the mounting surfaceis adequate to support the radio’s 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 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 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 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 thecurrent to be carried and length of the added lead.