Towertalk
[Top] [All Lists]

Re: [TowerTalk] TowerTalk Digest, Vol 133, Issue 49, siren

To: towertalk-bounces@contesting.com, towertalk@contesting.com
Subject: Re: [TowerTalk] TowerTalk Digest, Vol 133, Issue 49, siren
From: "Patrick Greenlee" <patrick_g@windstream.net>
Date: Wed, 22 Jan 2014 13:17:54 -0600
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
In the olden days back before Radio Shack became a cell phone boutique they sold DIY alarm components and systems which included electric motor driven siren (cast aluminum horn and rotating component) using the equivalent of an automotive heater fan motor. These things were very loud but had a slight drawback. You needed to drive them intermittently as when fully run up to speed the sound emitted was very high pitch into ultrasonic. Running them intermittently a few seconds on and a few seconds off gave a sliding tone WAILING that was an attention getter.

Now days solid state systems have essentially replaced most motor driven sirens. Reliability? I don't know, my sirens are 40-45 years old and still work perfectly.

Don't forget a good strobe light to attract attention at night. Nefarious activities tend to favor quiet and dark. Loud noise and bright lights tend to deter nocturnal mischief. Even IR operated security lights help.

Patrick NJ5G


-----Original Message----- From: Spencer
Sent: Tuesday, January 21, 2014 10:58 PM
To: towertalk@contesting.com
Subject: [TowerTalk] TowerTalk Digest, Vol 133, Issue 49, siren

I have a LOUD one, 12" diameter and a automotive starter motor spins it.
Quite effective!
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>