POWER n auto power off period.
n is in the range 10-255 and is the number of 5 second periods.
will switch HUNTER off after 1 min.
will prevent timed switch off.
POWER 0 will enable the power off key after POWER CONT has been executed.
To remind the user that HUNTER has been left switched on, HUNTER will emit a bleep every 150 seconds. Power n is reset to the default value (n=60, or 5 minutes) after power off/on and should be re-initialised by the user's program.