Radar detector sound output to drive warning light?

[crash99]

Hey guys - I have a cheap Cobra detector. I know, I know, you get what you pay for and it aint flash but does the basics. However while it has a reasonably loud speaker (but no aux audio output) I had this brilliant idea to make sure I get as early warning as possible: hook up a light/led or whatever from the sound output and stick it on my windscreen. As fars as I can tell the speaker has about 0.8A across the terminals when its on full volume. Any thoughts as to whether my idea will work and what type of light might work? (Please dont get too technical cos I aint!) Thanks.

[MaxB]

Just an idea but places like Jaycar sell things like LED sound level kits.

You could replace the microphone input from one of those with the output from your speaker.

A lot of riders use in-helmet LEDs like in those HARD kits. The idea being that you can easily miss a light on your winscreen.

[Warr]

Check the stats on a small reed relay.. J-Car should be able to supply.
Use the relay to drive a LED or whatever.

[notme]

Hmmm this always comes up....

there are many homebrew ways to do this, usually involving a solid state relay. Search the boards - here's one: http://www.kiwibiker.co.nz/forums/showthread.php/83459-Homemade-radar-screamer

The ideal "proper" way to do this would be a simple interface circuit, maybe adjustable sensitivity, that turns on an LED or whatever while protecting the radar detector headphone output. I might have a looksee how expensive that would be all up, if people are interested.