This morning, I was watching the local Chicago news on TV, and a video segment came up about the Metra’s tower at the A2 interlock near Grand Avenue and Western that was built in 1907. The switching system inside was state-of-the-art when it was installed in 1932. It is still in use for Chicago commuter trains.
I started a thread about this switching tower and its ancient technology over on the Trains Forum, but I thought that I would post a link to the thread here on the General Discussion Forum for those who might be interested but might otherwise miss the thread.
Here in the Mid Atlantic, on what is now CSX, the B&O color postion light signal system installed in the late 1920’s, is just now, as we speak, being replaced with moden signals. Over 80 years of service, with few upgrades, just repairs, the same relay operated block siginals and CTC signals have been at work.
The only real changes in all that time have been at the point of input control for CTC, once done by local towers, now done by dispatchers with computers hundreds of mles away - but those computers simply talke to the same old relay system installed way back then.
Only time will tell if the new system lasts as long?
As a side note, on my model railroad the intergrated signal system, turnout control system, CTC system and cab control system use similar circuitry and methods to that used on these 80 years old real life signals.
The Lake St tower is even bigger and still in pristine condition. The top of the lever case is glass and you can see all the contacts and relays inside. Its a “pistol grip” tower. The EJE tower in W Chicago is the same style but the facility has not been maintained to the same pristine condition.
In that time period like many other things for the railways it was designed to last at least 25 years, often longer.
The problem is if it is broken spare parts are now some thing of a problem.
Only so much electrical tape cable ties and chewing gum you can use to hold things together
These days railways tend NOT to have there own signal workshops like they did in the past so manufacturing of new parts and relay overhauls can’t be easily done.
Unless by one of the railway signal contractors at great expense.
Railway signal relays are a high speck specialised relay no one else uses them so heart attack pricing is the norm.
