Unitrol 800 project update. So far so good. I was able to get the siren working today by replacing the dead SP3099 output transistors with Mospec 2N5683 PNP transistors. Powered up the unit and had full siren audio output. Tried the PA function but only heard clicking noises in the speaker when pres...

Hello to the group. I'm hoping someone can help. I have an old Unitrol 800 series siren that has 2 blown SP3099 power output transistors. They are a TO-3 style matched pair and located on the bottom of the unit. Does anyone know of equivalent replacements for these transistors? I can't seem to find ...