Sanyo
ICR-B220 Instruction Manual page 23

Erasing all memories
1. Press the ERASE button four times. "ERASE ALL MEMORY" blinks.
2. While "ERASE ALL MEMORY" is blinking, press the TIME/SET button.
"ERASE" appears briefly. All memories in all folders are erased.
Example:
USER-01
LE 1/ 1
NEW
Note:
The ERASE button will not function during recording or playback.
When "ERASE ALL MEMORY" is implemented, all memories in all
folders in the SD Card are erased.
"." Blinks on the display while erasing.
Example:
ERASE.
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