Quick answer

Place door and window alarms on the inside frame, near the latch, so the sensor and magnet separate when the door or window opens. For the VOXON Door Alarm, stick the larger unit on the fixed frame and the magnet on the moving part, keeping the gap under 0.78 inches.

Why placement matters more than the alarm itself

A loud alarm is useless if the sensor and magnet don't align properly. The VOXON Door Alarm activates when the gap exceeds 0.78 inches (about the width of a finger). If you mount the pieces too far apart, the alarm may trigger falsely—or not at all when a door opens.

The most common mistake is placing the alarm on the door frame and the magnet on the door, but reversing them can cause misalignment. Always attach the larger unit (with the speaker) to the fixed frame and the smaller magnet to the moving door or window.

Trade-off: chime vs alarm mode

For exterior doors, use ALARM mode (100 dB) to deter intruders. For interior doors or windows near pools or sheds, CHIME mode gives a gentle alert without startling kids or pets. The VOXON unit lets you switch between OFF, CHIME, and ALARM with a simple slide.

Step-by-step door alarm placement

  1. Choose the right entry point: Start with ground-floor doors and windows that are out of sight from neighbors. Also consider sliding glass doors, garage side doors, and windows near fire escapes. Skip windows that are always locked or blocked by furniture.
  2. Clean the mounting surface: Wipe the frame and the moving part with rubbing alcohol. Let it dry completely. Dust or grease will weaken the adhesive and cause the alarm to fall off. Avoid mounting on textured or painted surfaces—the adhesive may not hold.
  3. Attach the alarm unit to the fixed frame: Peel the backing and press the larger unit onto the inside of the door or window frame, about 1–2 inches from the latch. Make sure the side with the sensor faces the moving part. If the frame is too narrow, mount the alarm on the wall beside the frame instead.
  4. Align and attach the magnet: Close the door or window. Stick the magnet onto the moving part directly opposite the sensor line on the alarm unit. The gap should be less than 0.78 inches when closed. Test by opening the door slowly—if the alarm doesn't sound within an inch of opening, reposition the magnet.
  5. Select the mode and test: Slide the switch to ALARM for a loud 100 dB blast, or CHIME for a soft tone. Open and close the door several times to confirm the alarm triggers and stops correctly. If false alarms happen, the gap is too small or the pieces are too close to a hinge.

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