How to Erase Sony Microcassettes

By Fred Decker

Although microcassettes from manufacturers such as Sony have been largely superseded by digital voice recorders, they're still available and in widespread use. Cassettes can be erased and re-used multiple times, which makes this a low-cost technology. Businesses must sometimes erase recordings from microcassettes before disposal, especially if they contain confidential information such as legal or medical consultations. One cassette at a time can be erased in the recorder, or they can be erased through the use of a magnetic bulk tape eraser/degausser.

Single Tape

Step 1

Insert the microcassette into your recorder. If your recorder offers multiple tape speeds -- usually 1.2 and 2.4 centimeters per second -- choose the higher speed.

Step 2

Insert a dummy microphone into the mic jack. Many recorders came with a dummy microphone, which is just a microphone plug with no wiring attached. If you don't have one, plug a set of earbuds into the microphone jack.

Press the "Record" button on your recorder, and let it record over the full length of the tape. When finished, remove the microcassette and reuse or discard it.

Bulk Tape Eraser

Step 1

Gather your microcassettes together at a work space that's at least five feet from the nearest computer or other delicate electronic device. Remove your watch, and place it at least five feet way.

Step 2

Hold the bulk tape eraser away from the cassettes, and slide its thumb switch to the "On" position.

Step 3

Position the eraser on top of your first cassette, and move it in a circular pattern for six to 10 seconds to erase the tape.

Step 4

Repeat, until you reach the duty cycle for your eraser. For an inexpensive consumer model, that's usually one minute or six to seven microcassettes.

Move the eraser away from the tapes by 2 to 3 feet, then release the "On" button. Rest the bulk eraser for at least 20 minutes before blanking your next batch of microcassettes.