EOWS

	EOWS series
	[[File:\|200px]]
Company	Federal Signal Corporation
Produced	1981-2001, 612 available on special order up to 2007
Type	Electronic
Sound output	113-124
Succeeded by	Modulator & DSA
Documentation	; Product sheet

The EOWS series (Electronic Outdoor Warning Siren) was a line of electronic sirens produced by Federal Signal Corporation.

Early Production

The EOWS series came to light in 1982 when Federal Signal won a bid for an electronic siren system to be installed at the now coal-fired Zimmer nuclear plant. Federal Signal however did not have an electronic siren line, so this led to a new development they called SiraTone. Federal Signal produced around 30 prototype model EOWS*1212 sirens for the plant system. You may notice that these sirens look identical to the 115, but they are 1212s as stated by the documentation tied with them. The original system of prototype 1212s were later absorbed into surrounding communities after the Zimmer nuclear plant fell through. A few can be found today still in service, however most are on newer controllers. Federal created a very simple, yet effective electronic siren. It was a cluster of 12 speakers consisting of rectangular re-entrant horns made out of fiberglass, sourced from Atlas Sound along with the 100 Watt compression drivers behind them. The frame/enclosure was made custom by Federal Signal themselves.

Further Expansion

After Federal Signal created this new product, they worked out some kinks with the SiraTone controller and expanded upon their electronic line with the introduction of the models 408, 812, and M*12. The 408 and 812 were rotating beam sirens made for better sound concentration and projection, while the M*12 was simply a mobile vehicular siren aimed for public events and such. Despite these new additions, the 1212 was still available as the only omni-directional model they offered. However, they changed the name from 1212 to 115. The reasoning behind the name change is unknown. In early stages, the EOWS*812 and 408 were made in a more "compact" manner with the projection horns recessing into the rear frame. This was very short lived and ditched by 1983, with the horns being mounted directly to the frame wall.

Federal chose a very simple way of manufacturing, essentially making a rotating sign with speakers attached to it through partnership with Dynapac Rotating Inc. While this was proven to be very effective, it was rather strange to see this when other manufacturers opted to create their own rotating mechanisms. Nevertheless, the rotating arrays featured Dynapac's K-25 rotator with a quad-brush collector ring assembly allowing the arrays to rotate a full 360° stall free, requiring little to no maintenance.

About two years later, Federal Signal introduced 2 new EOWS products, the 1212 and 612. Model 1212 was simply the 115 with the 408 and 812's spun aluminum projectors replacing the original rectangular fiberglass ones on the 115, for the sake of being uniform with the rest of the product line and a small boost in performance. Model 612 was a combination of the 408 and 812. It performed identically to the 812 while staying relatively compact like the 408. It also used less materials than the 812, making it much more economical, not to mention easier to handle/manage. With the introduction of said models, came the discontinuation of the 812 and 408 sometime in 1984. However the 115 stayed around a little longer as a cheaper variant that performed a little worse than the 1212. Discontinuation of the M*12 is unknown.

Late Production and Discontinuation

Federal Signal continued production of model 1212, 115 and 612 for a few years, eventually killing off the 115 sometime in 1988 or 89. The 90's rolled around and things started to change quite a bit. Federal Signal created a new omni-directional siren named the Modulator, leading to the demise of the EOWS*1212. However, Federal Signal kept the 612 in production, likely because it was their only rotating electronic siren at the time, it was efficient and powerful, and people still wanted to purchase them. They kept it up to date as well, modernizing it with their latest MC controller at the time. The EOWS*612 stuck around for many years into the future. However, Federal Signal removed it from their public websites in 2001 and only offered it as a special order model from 2001 up into 2007, with sales ending completely that year. Federal Signal unfortunately had to discontinue production on the EOWS*612 because they could no longer get speakers for them. Altec Lansing almost went bankrupt, meaning they had to do major budget cuts. To cut their losses, they killed off their University Sound branch, leaving Federal with no source for speakers that matched the 612's bolt pattern and size.

Modern Use

All EOWS units are fairly simplistic electronic sirens, and are easy to update with modern hardware. Many units still in service are on the latest UltraVoice controller from Federal Signal. Many are on older Federal controllers, like the MC and MCP. Some units are even on third party controllers like ones by American Signal Corporation as well as Whelen Engineering. The units were originally manufactured with simple common components, meaning they were easy to repair if needed.

While the 612 was still in production, it received upgrades from Federal Signal with their newer MC controller, then the MCP controller, and later their UV controller. Federal Signal still supports EOWS*612 too. The UltraVoice controller openly states it's compatibility with the 612 in its documentation, earlier documentation stated it's compatibility with the 1212 as well. However, UV isn't limited to just the 612 and 1212. Any model EOWS siren is fully compatible with the UV. A few EOWS*408 units in Massachusetts were fitted with UltraVoice controllers in the early 2000s. Unfortunately these units were replaced by Modulator 5020s in the mid-2000s.

Models

There were a total of 6 mainstream models in the series:

Model	Output	Drivers	Notes
EOWS*115	113 dBc	12 (1 per horn)	The earliest model in the series. Uncommon.
EOWS*408	119 dBc	8 (2 per horn)	The smallest rotating siren in the series. Rather uncommon.
EOWS*612	124 dBc	12 (2 per horn)	The most popular model. Many active examples can still be found today.
EOWS*812	124 dBc	12 (2 per horn for middle 4 horns, and 1 per horn for top and bottom 2 horns)	The largest siren in the series. Rather uncommon.
EOWS*1212	115 dBc	12 (1 per horn)	The successor to the 115.
EOWS*M12	123 dBc	4 (1 per horn)	Vehicular model. Decibel rating was measured at ten feet.^[1]