Reed Relays and
Electronics India Limited
Manufacturer of Reed Switches, Reed Sensors and Reed-based products
Reed Relays and Electronics India Limited Incorporated in 1971

Magnet sensors in Musical Greeting Cards

electronic greeting card
Greeting Card

Even in the digital age of Smart phones, people do like to mail out or hand over greeting cards taped to gifts, to celebrate an occasion or to express a sentiment. Some greeting cards play music or sound when they are opened and these are handmade cards which play traditional celebration songs using an embedded PCB which does the job.

Obviously the song should be played only when the card is opened, and this is achieved with a tiny flat magnet and a sensor mounted inside the card, under the glued on paper flap. Ultra miniature reed switches or tiny Magnet Sensors are used in musical greeting cards with appropriate magnets, to play a tune whenever the card is opened. Compared to the additional circuitry for the musical tones and the speaker, the reed switch bulk is much less. Normally open or Normally Closed versions can be used.

Application Classification

Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or Relay, Temperature Sensing or Magnet Biasing types. This application is classified as follows and the link gives more information on best practices to help select the most suitable AT band and matching magnet.

Position sensing Type

Position sensing Position Sensing type application When an application requires the end position of a movement sensed, or the sensing of a part when it Continue reading ->

Nov 7, 2020

The Reed Switches and Sensors used in such applications need to be robust, durable and efficient in meeting a high life expectancy. Our engineers work hard in life testing our products under various conditions, and our intention is to ensure end product durability and life. Although we wouldn’t want to restrict any of our products for use in only certain applications, the recommended products for use in this application are listed below.

UM-0018-M Ultra Miniature Reed Switch

Ultra Miniature Reed Switch Size 5 mm This highly sensitive, Form A type, UM-0018-M Ultra Miniature Reed Switches are designed for switching high speed signal loads with an Continue reading ->

Nov 8, 2022

UM-0018-H Ultra Miniature Reed Switch

Ultra Miniature Reed Switch Size 7 mm These highly sensitive, Ultra Miniature Form A reed switches are designed for low power, high speed switching applications and Continue reading ->

Nov 8, 2022

MS-212 Ultra-miniature Cylindrical Sensor

Ultra miniature cylindrical sensor icon MS-212 Magnet Sensor Drawing starFeatures10W Contact Rating. Normally Open contact. Two sensitivity bands. Sputtered Ruthenium Continue reading ->

Oct 30, 2020