From the manual for the AOR AR8600, which is readily available for download online, section 103 addresses Keylock:
1-3 Attention while operating
1. Certain key operations are acted upon when the key is RELEASED, not while it is pressed.
Allow time for the AR8600 to register such actions before pressing another key.
2. The keylock K.L. is intentionally made to be difficult to operate to prevent accidental operation.
To release keylock, K.L. the key has to be held for more than one second, the key legend on the
LCD confirms operation. K.L. The key is disabled during keying sequences (such as when
entering frequencies).
3. If a key sequence is not completed, the microprocessor will automatically abort most operations
after about 90 seconds of keypad inactivity.
4. Currently displayed VFO data is saved at power down (to increase speed of operation and to
reduce write cycles). For this reason, if the AR8600 is powered down using the PWR/VOL control or
external power is removed (without the optional internal BP8600 battery fitted or becomes
exhausted), the last displayed frequency will be lost and the frequency used prior to this will be
displayed when next powered up.
K. L.
The KEY LOCK is intentionally small to reduce the chances of accidental operation. Key
lock is useful when you do not wish an important frequency to be lost or the AR8600 to be
incorrectly set to a different frequency. The key lock status is not deactivated by switch
off / on, the STBY and MONI and keys are not affected by key lock.
PRESS K.L. to toggle the key lock on /off, an LCD key symbol “key image ” indicates status.