Gray alert & single tone sirens.

[Ohio_Man]

I found an old video on YouTube of a model 5 doing what someone in the comments called "gray alert". Basically what a 3T22 or Thunderbolt 1003 would do in pulse but for a single tone siren rather than a dual tone.

I figure this is what the damper on the STH-C would be used for, but I can't find on Google an answer to what gray alert would instruct civilians to do.

Also can anyone confirm or deny the existence of other sirens with dampers? (Eg: soundmasters, models 2's banshees)

Here's a link to the video:

https://www.google.com/url?sa=t&source= ... 2KT19p0Deu

[WPS4004Man]

I'm not sure what it means for this specific siren, but as I remember, for Civil Defense sirens, Pulse was generally used to signify radioactive fallout after a bomb exploded. Then again, I’m not sure what this siren was used for, so I could be drastically wrong.

[jacob585]

I'm not sure what it means for this specific siren, but as I remember, for Civil Defense sirens, Pulse was generally used to signify radioactive fallout after a bomb exploded. Then again, I’m not sure what this siren was used for, so I could be drastically wrong.

Not to get off topic but don't you think the reason they never adapted the system of 3 signal sirens doing pulse was because after a nuclear detonation most power would be knocked out that meaning sirens too?

[SirensOfNewYork]

That reminds me of this Klaxon CS6.
https://www.youtube.com/watch?v=Ae3uTTdfQGg it winds up and then the shutter kicks in.

[Chem_Boffin_6589]

ACA, in their promotional tapes, labelled the third signal capability as "local code" and not an explicit purpose, thusly enabling the siren to be used for another things like fire or imminent radiation etc. The damper for the siren in the video seems to be wired up to the motor starter, so it opens up when the motor turns on. There is another video of it doing a short blast that supports this. However, this could be the third signal being used for everything, but this video shows how it's supposed to be done on a coded Federal siren, with the silent time being the code given:


https://www.youtube.com/watch?v=27t_FQrUap0

----

Here, in the UK, we did have a version of said "grey signal", called the Black Warning, and it's from this I suspect the grey signal throty stemmed from. We had 3 warnings: Black, Red and White, with Red being the attack imminent signal, White being all-clear, and Black being fallout imminent. I believe this is true with this Grey signal. An early 1960s Civil Defence video showed examples of the Black warning which included a coded siren and explosive charges, to signal the need to go inside and seek shelter. The coded siren sounded the pulse signal, however this method hasn't showed up ever since. Instead, "Maroon" explosive charges were used in the local communites to signify the Black warning, triggered by the ROC monitoring bunkers and police officers. This is most likely because of the realisation that the mains-powered sirens would be knocked out of service when the bomb hit and the explosives could be packed in a bomb-proof container until they're ready for use. Instead of using the third signal for the black warning, people used it to differentiate their local warnings from the ones provided by the Home Office, hence why Broadmoor's warning was presumably Hi-Lo, and also why the Solutia plant sirens only have 3 signals. If, however, the contract with Hörmann didn't fall through, the system of >1000 F71s nationwide (which would have been independent of the mains electrical supply) would have used the Atomic, Biological, Chemical (ABC) signal you hear people test their privately owned sirens in Germany with. But, unfortunately, that never came to be, and so the Black warning, like the Grey signal, would be very ineffective in terms of warning anyone after the bomb hit.


EDIT:
Here's what ringbell.co.uk says about it:

"The 'GREY WARNING' was intended to give a one hour notice of impending fallout, by using a siren fitted with flaps to interrupt a steady siren sound. As alternative the ringing of church bells, or in Scotland where church bells are not in common use, by whistle. The proposed use of a Grey Warning was abandoned by the early nineteen sixties."

[Chicagosiren-hunters]

IIRC the “grey warning” tone signaled that fallout was expected within the hour. The sirens with coding mechanisms would then do a hybrid attack, kinda similar to ASC’s fire signal, but the damper would shut on the wind down. Kinda like this:


https://www.youtube.com/watch?v=-hUD2R4UXvs

[Ziginox]

IIRC the “grey warning” tone signaled that fallout was expected within the hour. The sirens with coding mechanisms would then do a hybrid attack, kinda similar to ASC’s fire signal, but the damper would shut on the wind down. Kinda like this:


https://www.youtube.com/watch?v=-hUD2R4UXvs

That's the video linked in the original post.