chirp on demand?

^^^^   Exactly, that way you can use a small momentary pushbutton switch. Like http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5fid=275-1571 that switch only accepts 0.5 amp but it is nice and small, you you could put it almost anywhere, and using it to control a relay you can control up to 30amps if you had to. Plus it is usually easier to replace a relay then it is to replace a switch. Even though your car will probably die before the relay or switch for how much you will probably use it.Will              Just my $00.02

97 Chevy K1500 5.7L w/ Clifford Matrix RS2

BTW I am not a professional(well at procrastination maybe)

Be Gentle, I'm new to this :-)

^^^^ if you are going to do that, just make sure that the switch that you get can handle the amperage that the siren is going to use. Otherwise you will have a fried switch in no time at all, almost instantly .Will              Just my $00.02

97 Chevy K1500 5.7L w/ Clifford Matrix RS2

BTW I am not a professional(well at procrastination maybe)

Be Gentle, I'm new to this :-)