Wed Jun 07, 2023 2:28 am
I would like to add, if you are having any trouble with that control unit:
If you can trace out what is going on with the in-tact wiring to the best of your ability, I could take a crack at figuring out what to do with the rest of the cut wires to get this thing operating. A large part of my job involves industrial control circuits like this, albeit with more modern components. The concepts are the same.
It would be helpful to peek under the black thing (cover?) that has the "18" and "19" labels on it to confirm what I suspect is under there (normally-open contact pair?), if it is easily removed.
A digital multimeter will be handy for checking things. A cheapie will suffice if you don't have one already.
Assuming the contactor and relay coils are still good (the multimeter will tell you) everything is likely still in working order. The contacts on these devices may benefit from an easy cleaning but otherwise there isn't much there to go wrong.
Overall looks like a very achievable restoration project given the skills you've already shown with the siren itself.
Beware those who teach not how to think, but what to think.