Icom IC-7700 Instruction Manual - Page 186

13 MAINTENANCE ■ Opening the transceiver's case Follow the case opening procedures shown here when you want to replace the clock backup battery or internal fuse. CAUTION!: DISCONNECT the AC power cable from the transceiver before performing any work on the transceiver. Otherwise, there is danger of electric shock and/or equipment damage. CAUTION!: The transceiver weighs approx. 22.5 kg (50 lb). Always have two people available to lift or turn over the transceiver. q Remove the rack mounting handles from both sides. See p. 2-3 for rack mounting handle detachment details. w Remove the 8 screws from the top of the transceiver and the 6 screws from the sides, then lift up the top cover. e Turn the transceiver upside-down. CAUTION: NEVER HOLD THE MAIN DIAL OR ANY OTHER KNOBS when the transceiver is being turned upside down. This may damage the transceiver. r Remove 7 screws from the bottom, then lift up the bottom cover. ■ Clock backup battery replacement The IC-7700 has a lithium backup battery (CR2032) inside for clock and timer functions. The usual life of the backup battery is approximately 2 years. When the backup battery is discharged, the transceiver transmits and receives normally but cannot retain the current time. WARNING: DISCONNECT the AC power cable from the AC outlet before removing the transceiver's cover. q Remove the top cover as shown above. w Replace the clock backup battery, located on the front panel as illustrated at left. • Make sure the battery polarity is correct. e Return the top cover to the original position. r Set the date and time in time set mode. (p. 11-2) 13-6