Activate a 12v relay with a 1.5v source

Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=28626
Printed Date: July 17, 2025 at 10:09 PM

Topic: Activate a 12v relay with a 1.5v source

Posted By: haven4me
Subject: Activate a 12v relay with a 1.5v source
Date Posted: March 18, 2004 at 6:52 PM

Ok, heres the question...how do I trigger a 12v spdt relay with a 1.5 volt source(pager)? I am using a pager to activate an array of relays that will remote start my bike. The pager does not have enough voltage to trigger the first relay so I want to trigger the relay via the unknown component. PLEASE HELP! Running out of time on this one. Any advise on what part to use and where to get it would be greatly appreciated.

Mike

Sacramento

916-729-2223

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Everything I know is only for today!

Replies:

Posted By: xetmes
Date Posted: March 18, 2004 at 8:54 PM

easy, use a transistor to sink current on the relay, search on these forums for "transistor" and you should get some diagrams...

Posted By: auex
Date Posted: March 18, 2004 at 10:54 PM

Are you sure that you aren't trying to make a remote detonator? Just kidding.

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