Hi MtnMan. I have a GE Powercall siren circa 1980. When it's turned on, you can barely get a tone from the speaker. You can hear it, but it's only a whisper. I would like to get you to look at it. I have it attached to a 24 volt system on an 85 AMG 5 ton truck that my organization uses for parades. It worked fine up until a couple months ago. Can you contact me at firstname.lastname@example.org?