siren/pa

I seem to be having siren issues with my trunk mount VHF XTL5000 with a W9 head. The siren used to work fine until my radio suddenly wouldn't boot when starting my car. It would only flash the backlight for a split second, turn off, then flash again until the ignition was turned off. The radio...

Hello All, I have read on numerous forms and sites that it is possible to combine a VRS and Siren/PA box. The thing I cannot find is any proof or documentation on how to do it? I am very interested in doing this but would like to have a preview of what is involved. I have recently...