# Doorbell with strobes (and use of relay??)

**URL:** <https://boards.straightdope.com/t/doorbell-with-strobes-and-use-of-relay/689716>\
**Category:** Factual Questions\
**Created:** [May 31, 2014, 7:34pm UTC](https://boards.straightdope.com/t/doorbell-with-strobes-and-use-of-relay/689716 "2014-05-31T19:34:47Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![ToddFur](https://avatars.discourse-cdn.com/v4/letter/t/da6949/32.png) [@ToddFur](https://boards.straightdope.com/u/ToddFur)\
**Post date:** [May 31, 2014, 7:34pm UTC](https://boards.straightdope.com/t/doorbell-with-strobes-and-use-of-relay/689716/1 "2014-05-31T19:34:47Z")

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Hi-

I am Deaf myself and am trying to wire up my existing doorbell transformer to a 24vdc strobe light.

Obviously, the goal is that when the doorbell button is pressed, the strobe light would go off.

Right now if I wire up the transformer to the 24vdc strobe light, the strobe flashes non-stop. It’s almost as if I need something in between the 2 device to make the wire go “DEAD” and then “ON” when the doorbell button is pressed… a friend said I might need a “relay” but I don’t know enough about it… Does anyone know how this can be accomplished??

FYI, I am not interested in those pre-made wireless solutions they have for the Deaf on the market – I always get signal inferences causing the lights to go off when someone isn’t even at the door. So I would like for this hard-wiring solution to work somehow.

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**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\
**Post date:** [May 31, 2014, 9:03pm UTC](https://boards.straightdope.com/t/doorbell-with-strobes-and-use-of-relay/689716/2 "2014-05-31T21:03:28Z")

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you want the strobe light to be in the circuit the same as a door bell. the doorbell switch/button needs to be between the transformer and the strobe.

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**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\
**Post date:** [May 31, 2014, 9:07pm UTC](https://boards.straightdope.com/t/doorbell-with-strobes-and-use-of-relay/689716/3 "2014-05-31T21:07:16Z")

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Wire the strobe leads across the doorbell terminals.