Illinois Railway Museum Blog

One of the active members and volunteers in the Signal Department is Frank Carraro.  Here are pictures and a report submitted by Frank.  Good work, and thank you, Frank.

New Bungalow

If you haven't noticed the small aluminum building at the corner of the Office building on the Central Ave side, you should.  It is an "instrument hut" or "signal bungalow", and something important happened in it Saturday May 11th.  In particular, the first wire in the actual complex signal wiring was installed. 

Relay Rack

In the photo of the interior of the hut, the structure on the left is a rack of 74 relay plugboards. 

Relay Pugged In

In this photo you see one relay inserted in the board just to show what one looks like when plugged
in. 

First Wire

On the back side of the rack is much much of the wiring needed to make the whole thing work.  The wires are connected to a small metal clip which snaps into place so that the wire connects to the relay when it is plugged in.   In the next photo you see it being inserted into the proper slot.  The first wire that interconnects one relay to another. As you may guess this is very painstaking work.  A mistake can cause trouble the first time the whole thing is powered up, or years down the line when a signal gives an incorrect indication.  

The circuit drawings were created by Member John Wells, who is a professional signal designer.  Each wire is shown and has a name, such as "121HD3".  It has a starting point, such as "121EHDR-F1"   and and ending point such as "112TPPR-H4".   A small plastic wire tag is placed on the wire at each end when the wire is connected to the device.  Then, after double checking that the wire is connected where the tag says it is, the circuit print is marked out to show it's done.

When this hut is done - this fall maybe - it wiill be picked up and moved to the east end of the depot tracks, and after a lot more work, connected to the signals, and the newly installed switch machines it will control and then, by means of our CTC system, to the Dispatcher's control panel in Spaulding tower.

That's how our signal system expands.  One wire at a time.