Brushless motors and relays are irrelevant. Gasoline engines are essentially giant spark gap transmitters. Back on topic.

Gas engines throw off a large amount of EMF, could cause issues. With proper shielding, my Arduino was not able to deal with the low levels that were thrown off from a contactor.

I suggest using a Federal FC or a timer module, Arduinos are very susceptible to EMF and tend to get stuck on.

Ye olde Type 2. Late 40s-early 50s would be correct, 4 brush model. Hope they are in good condition, siren looks clean overall.

Good gust of wind probably knocked it loose, finback too. Not sure how rust affects these sirens, but it is possible the plate where the head attaches to the rotator has potential to fail as they age.

Looks to be in good condition. They avoided painting the tag, honestly refreshing to see.

These were produced by Wandel & Goltermann, likely an ESA. Sold during the cold war, they were one of the first German companies to dabble in electronic sirens, also producing equipment for emergency vehicles. Can't find too many in Germany anymore, but oddly enough there are a few ESAs in the B...

Photo was taken early 2000's.

Cool ambience, lots of echos. 11:52 test time. Post #1000!



https://www.youtube.com/watch?v=cMM0TSZDuoE

Lots of progress, can't wait to see it with the painted text. It is important to account for the lowered air resistance during tuning, as it can result in the siren running slower than intended after the restrictions are removed. Best to shoot for 3450RPM for optimal results.