The Siren Board

I work for a company at Midway Airport that handles the private jets. Years and years ago, we either leased or bought the old Chicago Fire Department that is adjacent to our main hangar and lobby. There is an old jailbar Thunderbolt that sits atop the old fire department building that was never taken down when Chicago decommissioned the old system. The building is now used to fix our ground service equipment. Some of my coworkers and I were talking about the storms that blew through on Sunday and how some people heard sirens and others didn't. One guy who runs the GSE shop asked me if I knew that we had an old Civil Defense siren on the roof. I said ya, but it's got to be dead. He said Oh no, it still works, I'll show you. I thought he was just kidding!

He took me into the basement of the old fire department (which is technically off limits because it has tons of asbestos in it) and there sits the box for the Thunderbolt. I'm no expert on panels, but it was an older one and I believe it actually said Federal Sign on it. He opened it up (no lock or anything) flipped on the rotator, blower, and chopper switch, and wouldn't you know it, the thing went off! Not only did it go off, it still rotates (2 RPM). Now the blower wasn't working, but my guess is it's just an old belt or something. I can't believe after all these years of no use and no maintenance that this thing still works. It goes to show you the dexterity and strength of an old design.

Does anyone have the history on Chicago's old sirens? I know it's been discussed before, but when were they commissioned and decommissioned when the new system was put in place?

Here's a Google Maps link to the siren

https://maps.google.com/maps?q=5880+s+c ... ,,1,-14.72

I pass that siren everyday on my way to work in Cicero. The old system was put in place in the 1950's. Mainly Model 5's, STL's, a few Chryslers and I believe a couple HOR's. Thunderbolts were added a little later. Some were not added until the 70's. The system was decommissioned between 1988 and 1992, only 15 would operate, keep in mind they were all landline. 1988 I believe was the last year they actually tested them and 1991 or 92 was when they actually unhooked controls and possibly removed some of the sirens. Most are gone now either way. New system was promised by Mayor Daley in 1993, but no sirens were installed until late 1997 and the system was finished and turned over in early 1998. 2 additional sirens were added in 2007, one 2001-B and one Modulator. All but one lone siren are pole mounted. Most on regular wooden poles, a couple downtown are on steel poles. (Vaults under street, could not set a wooden pole.) The sirens are silently tested every Monday morning around 7:30. Sirens rotate but do not sound. Then a 30 second blast on monthly test day. I believe the final number for the "new" system is 114 sirens within the city limits. The city lets a lot of things go, and sometimes take forever to fix things. But the sirens seem to be something they are insane about. They get fixed very quickly if there is a problem. I imagine the weekly silent checks find most of the problems, but I would say they probably don't have a lot of trouble with these sirens.

Brendan Ahern wrote:I pass that siren everyday on my way to work in Cicero. The old system was put in place in the 1950's. Mainly Model 5's, STL's, a few Chryslers and I believe a couple HOR's. Thunderbolts were added a little later. Some were not added until the 70's. The system was decommissioned between 1988 and 1992, only 15 would operate, keep in mind they were all landline. 1988 I believe was the last year they actually tested them and 1991 or 92 was when they actually unhooked controls and possibly removed some of the sirens. Most are gone now either way. New system was promised by Mayor Daley in 1993, but no sirens were installed until late 1997 and the system was finished and turned over in early 1998. 2 additional sirens were added in 2007, one 2001-B and one Modulator. All but one lone siren are pole mounted. Most on regular wooden poles, a couple downtown are on steel poles. (Vaults under street, could not set a wooden pole.) The sirens are silently tested every Monday morning around 7:30. Sirens rotate but do not sound. Then a 30 second blast on monthly test day. I believe the final number for the "new" system is 114 sirens within the city limits. The city lets a lot of things go, and sometimes take forever to fix things. But the sirens seem to be something they are insane about. They get fixed very quickly if there is a problem. I imagine the weekly silent checks find most of the problems, but I would say they probably don't have a lot of trouble with these sirens.

I have a photo that shows a Thunderbolt being installed on a fire station in Chicago. Its a jailbar and its dated 1952, therefore showing they were also installed when the first system was going up in the 50's.

Wow! That's amazing! It hasn't been ran or maintained for years yet it still runs! I guess that shows you the amazing quality of a Thunderbolt!

ACAP10 wrote:I work for a company at Midway Airport that handles the private jets. Years and years ago, we either leased or bought the old Chicago Fire Department that is adjacent to our main hangar and lobby. There is an old jailbar Thunderbolt that sits atop the old fire department building that was never taken down when Chicago decommissioned the old system. The building is now used to fix our ground service equipment. Some of my coworkers and I were talking about the storms that blew through on Sunday and how some people heard sirens and others didn't. One guy who runs the GSE shop asked me if I knew that we had an old Civil Defense siren on the roof. I said ya, but it's got to be dead. He said Oh no, it still works, I'll show you. I thought he was just kidding!

He took me into the basement of the old fire department (which is technically off limits because it has tons of asbestos in it) and there sits the box for the Thunderbolt. I'm no expert on panels, but it was an older one and I believe it actually said Federal Sign on it. He opened it up (no lock or anything) flipped on the rotator, blower, and chopper switch, and wouldn't you know it, the thing went off! Not only did it go off, it still rotates (2 RPM). Now the blower wasn't working, but my guess is it's just an old belt or something. I can't believe after all these years of no use and no maintenance that this thing still works. It goes to show you the dexterity and strength of an old design.

Does anyone have the history on Chicago's old sirens? I know it's been discussed before, but when were they commissioned and decommissioned when the new system was put in place?

Here's a Google Maps link to the siren

https://maps.google.com/maps?q=5880+s+c ... ,,1,-14.72

That's great! I can't believe it still worked! I guess it goes to show you that Federal sirens are quality!

Is it single or dual toned? I know Federal made a very small amount of dual toned grid-faced Thunderbolts. Does it still have an AR timer? I suppose it has the big 6M mega blower.

Brendan Ahern wrote:I pass that siren everyday on my way to work in Cicero.

Brendan did you notice it facing a little more southerly today? It stopped in almost the same direction it's been sitting for years, but if you look closely, it's definitely facing a bit more south.

I didn't see an AR timer on it, but I was only down there for a minute so it might be there. He turned it on using the RCM1A panel. I'll try and get some pictures at some point. The siren is single tone. Wish I could tell you what type of blower it has but I can't being that it doesn't work and it's on the roof.

The siren and boxes themselves are still in fantastic condition. Nothing was rusted on the boxes and the CD sticker was in good condition. The siren head looks like it was painted within the past couple years (it obviously hasn't.) The rotator box is a bit rusty on the outside, but obviously it still rotates so no big deal. I do believe the city of Chicago still owns the building it sits upon, so anyone looking to acquire it would probably have to talk to them first.

I have been in jury duty since Monday and will be going in to work at 2:30 today. So I will let you know. It has been pointing SW for a long time. But I'm sure someone has played with it in the last few years prior to you getting there. As far as the Tbolts being installed in the 70's, I did not say all of them were. A few were installed in the 50's. But most of Chicago's Tbolts were installed much later, most had screens. Some were even mounted on private buildings. Some are still there. As far as acquiring it, talk to someone at the Dept. of Aviation since it is on airport property and is probably controlled by them now. The biggest issue that I could think of is getting a crane in there. Not sure if they would let you with it being the airport. Even the traffic signals and street lights are much lower in that area. That could explain why it is still up. I'm just really surprised that it is still hooked up to power. Either way, you're lucky to have a Tbolt at work. All I have are 3 ATI's at my work.

Wow, I have seen this siren before, but never would have assumed it worked!

Does anyone have or know of a map for the old Chicago system?