============================================================================== K E N W O O D >>> A M A T E U R R A D I O S E R V I C E B U L L E T I N <<< ============================================================================== Kenwood Service Centers Kenwood Service Corporation Kenwood Service Center, East 2201 East Dominguez Street 829 Lynnhaven Parkway, Suite 130 Long Beach, California 90801 Virginia Beach, Virginia 23452 Telephone 1-310-639-5300 Telephone 1-804-340-1702 ============================================================================== BULLETIN # 5 MODEL: TS-700A SUBJECT: REPEATER OPERATION IN THE 145 MHZ BAND We have had several inquiries about repeater operation of the TS-700A in Europe. The 2 Meter band in Europe is 144 MHz to 146 MHz with repeater operation in the 145 MHz to 146 MHz range. The repeater offset is generally 600 KHz down from the output frequency. The re- peater offset in the TS-700A occurs only in the 146 MHz and 147 MHz bands. By changing these to 144 MHz and 145 MHz, respectively, and changing the appropriate offset, the TS-700A can be used with European repeaters. The TS-700A uses varicap diodes to tune the HET unit, MIX unit and RX NB unit because of the 4 MHz coverage. These varicap diodes are used to resonate various stages precluding the need to retune from band range to band range. The varicap diodes are biased by resistors that are selected by the BAND and REPEATER switches. These bias re- sistors must be changed if the band frequency and/or offset crystals are changed. The table below shows the resistors and crystals that need to be changed to make the TS-700A useable with European repeaters All resistors are 1/4 watt. HET UNIT Part No. 146-147 144-145 X3 127.100 MHz 125.100 MHz X4 128.100 MHz 126.100 MHz X6 128.700 MHz 125.500 MHz R31 62 K 39 K R32 82 K 47 K R34 100 K 39 K BAND SWITCH UNIT Part No. 146-147 144-145 R103 12 K 22 K R104 8.2 K 15 K R110 12 K 15 K R112 6.8 K delete R113 6.8 K 18 K ADD 138K It is necessary to remove the front panel to make this modification. To do this, remove the top and bottom cabinet halves. Next, remove the FINAL tuning shaft by loosening the shaft coupling and pulling the knob and shaft out. Then, remove the six screws ( 3 on each side) holding the front panel. Remove the BAND and DRIVE knobs and the nuts holding these controls. Gently pull the front panel out until there is enough room to work on the BAND SWITCH unit. (It is located on the back of the band switch.) At this point, you will be able to change the resistors indicated on the BAND SWITCH unit. The 138K resistor that is to be added consists of a 120 k resistor and a 18K resistor in series. It is connected from pin 3 of the band switch to ground. After installing the new resistors in the BAND SWITCH unit, re- assemble the front panel, leaving out the FINAL tuning shaft. The procedure for replacing the resistors in the HET unit is to first remove the three screws holding the board and tilt it up towards the VFO. Plugs P-1 and P-2 may be removed if necessary. The re- sistors that need to be changed are located on the outside edge of the board. Replace the resistors and reinstall the board and con- nectors. Install the crystals in the appropriate sockets (X-3, X-4, and X-6). Replace the FINAL tuning shaft and align as per page 40 of the Service Manual.