The Siren Board

I've been wondering for a while and its been bugging the crap out of me so what happened.

Because the Modulator is a vastly superior, configurable, easily serviceable, true 360º omnidirectional unit, unlike the 1212, which is limited to one configuration and relies on closely spaced Atlas speakers. The 612 lived on until the early 2000s (or so it was on Federal's industrial site then). Its not like Federal ever came and submitted a press release explaining where it went, but it could have been a number of things. Low sales, emphasis on the superiority of omnidirectionality in electronic sirens, condensation of the product line, etc.

The SiraTone controller was also a product of rapid development. The MC controller improved the circuitry while making the box configurable for the Modulators up to the 6024, whereas the SiraTone controller was limited to six 200 watt amps.

Well you got to remember that the EOWS 408,612,and 816 were all different combinations for a rotating electric siren and looking at the design it looks pretty simple to maintain if needed, so that's a win/win on omni and uni directional sirens with the Modulator and EOWS series.

Didn't they have lots of reliability issues?

Yes, they had lots of issues. Most of them being the poor reliability of the original siratone controllers.

Plus, collector rings on an electronic siren are a BAD idea.

holler wrote: Plus, collector rings on an electronic siren are a BAD idea.

this is why rotating Whelens don't go around in a complete revolution; They rotate about 350°, stop, then turn back the other way. I don't know if they use clocksprings or just wire with good strain relief.

Jim Z wrote:

holler wrote: Plus, collector rings on an electronic siren are a BAD idea.

this is why rotating Whelens don't go around in a complete revolution; They rotate about 350°, stop, then turn back the other way. I don't know if they use clocksprings or just wire with good strain relief.

Do all sirens that rotate 360 deg. need collector rings or just curtain ones?

Thunderbolt10031 wrote:

Jim Z wrote:

holler wrote: Plus, collector rings on an electronic siren are a BAD idea.

this is why rotating Whelens don't go around in a complete revolution; They rotate about 350°, stop, then turn back the other way. I don't know if they use clocksprings or just wire with good strain relief.

Do all sirens that rotate 360 deg. need collector rings or just curtain ones?

All sirens that rotate 365 deg. need collector rings because other wise the wires will get completely twisted around in the rotator. That is why Wheelen does the notorious 370 deg. then does it the other way so that way the wires in the rotator do not get twisted around in the rotator. Eventually if you put enough tension on the wires they will either come loose or com off the part of the siren they are connected to and then your siren is broken.

Jim Z wrote:I don't know if they use clocksprings or just wire with good strain relief.

They use limit switches with good wire.

Thunderbolt10031 wrote:

Jim Z wrote:

holler wrote: Plus, collector rings on an electronic siren are a BAD idea.

this is why rotating Whelens don't go around in a complete revolution; They rotate about 350°, stop, then turn back the other way. I don't know if they use clocksprings or just wire with good strain relief.

Do all sirens that rotate 360 deg. need collector rings or just curtain ones?

more or less, yeah. You can't just run wire up to the motor/speakers because it'll twist and eventually break. Car steering wheels can make a few complete revolutions because they use clocksprings; it's not actually a "spring" but a coiled flat cable which is wound in a spiral that looks like a clock spring. Even then, they can only turn a few complete revolutions before they have to be turned back the other way.

collector/slip rings and brushes are fine for a mechanical siren; the motor's armature is heavy enough where its inertia will keep it spinning through any minor glitches in the power transmission from the rings to the brushes sliding across them. They have to be in really really bad shape before you'll start hearing problems in the siren's operation. On the other hand, with an electronic siren, if you use slip rings to send the tones up to the speakers, any little glitch or arc between the brushes and the rings will be heard as popping and crackling from the speakers. And even good condition rings and brushes arc a little. Plus, electrical arcs throw off TONS of broadband radio noise which might cause problems with the electronics in the control cabinets.