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This area of the site is for discussing things related to Outdoor Warning Sirens.
All of the ACA Alertronic videos on youtube sound different to the ones that were in Sarnia, which had a hard windup and longish wind down. They were dual toned and had a unique, almost wonky timbre to them (like a dual toned Whelen 3016 or even a higher pitched EOWS 612 with a siratone cabinet, but still different then that). It's hard to remember since it's been at least 20 years since I've heard one live.

Sirendude purchased 2 of Sarnia's Alertronics and according to this thread https://www.thesirenboard.com/forums/vi ... hp?t=13976 I believe he had issues getting his siren to work and has since sold it. I hope the purchaser has better luck and a video camera. I am a newbee when it comes to Siren electronics, so I was wondering based off the control panel what yous could tell me about these, since the later ASC models sound much different. Any information would be much appreciated...thank you.

Here is a pic of the control panel, any information
https://www.google.ca/search?q=aca+aler ... l1KE5QLSGM:
The ASC controllers sound different because they're digital and not analogue, for starters, and are more simple I think because they don't need to generate the tones there and then.
The Controller for the siren is ACA's Compulert system. But is that what generated the actual tones in the siren, or is that a separate component? Judging by the picture there appears to be two separate set of buttons that control the siren tones in the control box. I am trying to find a manual online but I can't find any information on these.
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By DJ2226
You probably won't find a manual on these. Sorry in advance for the rather lengthy response.

Like most electronic sirens the thing on top of the pole is nothing more than a fancy supped up speaker, the tones come from the controller. While these are CompuLert panels they were built differently compared to today's sirens. Back when those sirens were built all of the major siren companies were producing sirens that were using analog logic based tone generators, meaning they used a number of components like capacitors, IC's, and timers to create the tone. Depending on the way they're designed they typically don't have the same peak pitch from siren to siren. For example analog Whelen sirens made after the company made the decision to use a lower pitch could peak out anywhere from 440 to 500 Hz in alert. For most of these companies they made a switch to digital controls sometime in the mid-90's that used microprocessors to create tone using software and programming. The digital ones aren't as liable to malfunction due to aging components. Whelen and ACA had some of the better designs from what I can gather. Even some of the oldest systems of Whelens and Alertronics in areas like St. Louis County, MO and Oak Ridge have shown to be almost as reliable as the newer sirens from their respective manufacturers aside from slight things like blown speakers and maybe some failed rotators. The EOWS series on the other hand was a mess. About every video of one online shows them either losing or gaining pitch as they run, and they aren't necessarily the most reliable when it comes to activations either.

ACA changed the schematic for their tone generators a couple of times. The video online of one from Sarnia's system sounded like it was driven by an UltraVoice almost. I remember it having a very quick linear wind up, so it appears that ACA designed the generators on those in a similar fashion to Federal's SiraTone controller logic. If I'm not mistaken they also sounded off with the same pitch combo of current dual tone UV's, MCP's, and MC's running at 850/1020 Hz. The closest siren I could find to those sound-wise was the video of one of Bolingbrook, IL's old sirens which happens to have the newer style head with 4 throats instead of 8 with the same wattage. Apparently whatever component controls the pitch on it failed allowing it to drift up in a similar way to what's seen on the SiraTone controllers. It's pretty apparent in the video it tried to hit around 850 Hz before drifting up, which leads me to believe it's a single tone version of that particular controller design. These lack a wind down. I think the FC's that controlled them would shut the whole panel off instead of tripping the input terminals on the board to cancel with a proper ramp down.


Another design they made was used on numerous sirens. Instead of the "5/6" pitch ratio these were "6/7." The newer digital ones use this ratio in their tones as well when dual tone is enabled. These had a slower wind up to them and bucked the norm for analog electronic sirens since the majority of the ones still standing run at exactly the same pitch in alert. They may have come in single tone as an option, but I'm not too sure. A few examples of these are the one in Amarillo, Rolling Meadows, and Kodiak. They also could ramp up softly like their modern counter parts. I'm under the assumption that these were the first to support sirens past 1600 watts. It seems that the sirens at Oak Ridge runs on these logic panels in single tone. Most of them peak out at around 610 Hz, which is right around the pitch of the low tone side of these sirens. Some also apparently ramp up softly as well. I think these were made slightly different or age has taken effect since some of them peak a little higher than others.

Attack: Both of the sirens heard in the background are dual tone, one's analog and the other digital. Digital dual toned ASC electronic siren panels are pretty rare.




Oak Ridge:


With this one it's pretty apparent that some are running slightly higher in pitch than others. You can also tell that they don't have that hard ramp up like the previous one.


Of course everything is digital now from most companies with the exception of Loudoun. I believe the earliest ones were installed in Iowa City possibly before they got the Whelens. Their system runs alert so I have no clue what the other tones sound like, but the reason why I assume these are the first is because they have the exact same pitch in alert as the current controls in attack, air horn, and wail. Of course nobody has ever recorded these testing, so there's no telling what the wind ups and wind downs sound like.


That's about as much explaining I can do as far as tone generation is concerned on these sirens. The oldest of the rotating Alertronic's (5000 and the 6000R's with P-15 rotators) may have sounded different, but we'll know what they sounded like until someone either finds a way to obtain one or find one that's still active. They seem to be made of unobtainium though, so we may never know.
Thank you very much for the information, much appreciated. The second video (Tsunami Siren in Kodiak Alaska) sounds pretty much dead on to what I remember the Alertronics of Sarnia tone was.

What little information that I gathered at the Sarnia library says that the city failed a nationwide fire drill in the fall of 1985, during the cold war. Our old system was 6 B&N Mobil Directo's. As a result, the Alertronics were erected in the spring of 1986, and I was told (though I am not sure it's true) they were donated from the U.S. department of the defense. I always assumed ASC renamed them after 1992 from Alertronic 6000 to RE-1600, and changed the design. I don't remember the tone(s) ever changing but the city pretty much gave up fixing them after 1994, which is the only time I saw one being tested in the flesh. That is also the last time I saw them ever being worked on. They used to malfunction quite a bit. Other then the recording from cousin heard online the last time I heard them (or one) was summer 96 during a severe thunderstorm. Only know one that survived which was sold last year. I regret not buying one in late 2012 after the city took them down.
Here are some more pictures for you. One of the sirens I used for parts and then I donated the siren shell to the Lambton Museum. The other I sold and have no update on if he managed to get it working.
IMG_1928.JPG (3.33 MiB) Viewed 1933 times
IMG_1924.JPG (3.04 MiB) Viewed 1933 times
IMG_1921.JPG (2.67 MiB) Viewed 1933 times
IMG_1835 2.jpg
IMG_1835 2.jpg (1.59 MiB) Viewed 1933 times
Would the radio controls have been inside or outside the main control box? I do remember wires running from the cities electrical poles to the sirens, which were obviously removed before 1997. Something that always puzzled me was the cities over use of growl testing these (which was a single 3 second whoop). It sounded great in the middle of the city, hearing this mass echo of whoops from all directions...Is growl testing done on using a timer or is it a simple flick of an on off switch?
Alertronic6000 wrote:
Sun Oct 15, 2017 12:16 pm
Would the radio controls have been inside or outside the main control box? I do remember wires running from the cities electrical poles to the sirens, which were obviously removed before 1997. Something that always puzzled me was the cities over use of growl testing these (which was a single 3 second whoop). It sounded great in the middle of the city, hearing this mass echo of whoops from all directions...Is growl testing done on using a timer or is it a simple flick of an on off switch?
Activation of signal then cancellation of signal after 3 seconds is my guess.

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