Basically looking to build a radar screamer without all the fancy hooha (and price tag) that accompany it...

I've got the siren, got a 12v 30a relay... What I can't figure out is how to make the speaker output on a radar detector transform into a +12v trigger to trigger the siren... Any idea?

Thanks. This would be an interesting write-up if anyone can let me know how to get around this kink, I'd be glad to post pics of the rest of my set up when complete...

This is mainly for my motorcycle, but could be useful over a loud stereo and open exhaust....

 

The speaker output from the radar detector could run a hidden speaker.... any hidden speaker. If you get a little tweeter or something and hide it under your dash, it would work fine. Plus it will save you the cost of the siren... which will hurt like a biatch if it goes off with you in the car. The problem is that the speaker output is A/C... and the siren is D/C. If you can find a D/C output in the detector somewhere (+ or -) I can tell you how to hook it up.