The Stovebolt Site Forums Project Journals Project Journals 1952 Chevrolet 3100 Project

The reason only one horn worked is because that high tone horn's electromagnet pulls its diaphram (the noise maker) and opens its switch before the low tone horn's electromagnet pulls its switch open. This happens because the hi-tone is designed to operate at a faster rate (higher tone). When either switch opens in your series circuit the spring in each horn will be pushing the diaphram back to its "at rest" position to close the switch and start the dance over again.