Basically second hand Federal sirens. Sacramento had a couple of them in their system.
Wait but how is that if Darley was also a second hand federal siren maker for a time?
W.S. Darley only used the cores (rotor/stator/motor assembly if you want) themselves, they came up with their own housings (IIRC) save for the Champion which has it's own in-house core (the intake being on the bottom, both on the 6-port and 12-port models, the 8-port model having two rotors)
18 years old french siren enthusiast, hailing from what was called "Picardy"
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