Unplug the Hamilton Beech Microwave Model P100N30ALS3B
MICROWAVES ARE EXTREMELY DANGEROUS TO WORK ON DUE TO THE HIGH VOLTAGE. REPAIRS SHOULD BE ACCOMPLISHED BY A PROFESSIONAL ELECTRONICS REPAIRPERSON.
Remove the 2 black screws from the sides. Remove the 2 regular silver screws from the back. Using a T20 torx wrench remove the 2 torx screws (I included a picture of torx wrenches with the female opening for the male pin). Slide the microwave cover back a bit and remove (there is a lip on the inside at the front of the unit which the frame fits into). DANGER!!
DANGER USE CAUTION IF YOU DARE TO PERFORM THIS MODIFICATION!!
The electronics are behind the key pad on the inside. Look for the light blue flexible wiring strip (it's about 2.5" wide with black wires imprinted on it). Just below and to the left of that is the beeper (black plastic inverted U shaped disk see right).
Carefully insert non-combustible, non-conductive padding to each side and secure with electrical tape. I placed electrical tape on the areas that might be exposed to current, including the small barrel shaped capacitor above and to the left of the beeper. If all
you used was electrical tape (and be very careful of what you are touching) it would reduce the sound some. I used cotton cosmetic pads cut to shape. When I finished, reassembled the unit and plugged it in the sound was reduced by a half at least. I just finished modifying mine, in the last hour. If you are not mechanical or electronics savvy, DO NOT ATTEMPT this modification. I assume no responsibility for incidents with regards to injury or *****. Update, I have been using the much quieter beeping microwave without incident. I'm still not used to how quiet it is. It's about 1/3 or even 1/4 of what it used to be.