Sony FD Trinitron WEGA KV-32HS20 Operating Instructions Manual page 58

Other Information
Tips
11 If more than one code number is listed, try entering them one by
one until you come to the correct code for your equipment.
J If you enter a new code number, the code number you previously
entered at that setting is erased.
-3 In some cases, you may not be able to operate your equipment
with the Sony remote control. In such cases, use the equipment's
own remote control unit.
LI Whenever you remove the batteries to replace them, the code
numbers may revert to the factory setting and must be reset.