Making a WE551A Functional - Work In Progress

[TelePlay]

The upper photo is kind of blurry: looks like camera shake and some reflections at the left, so reading the markings is difficult.

Almost looks like a depth of field issue, the camera focused well on the back board (BAT) but the items closer to the camera are out of focus, so it appears. Might need multiple photos of the upper to get the front and back items in focus separately,

[ramegoom]

THAT is good information. I'll get better pictures and look at that large cable. It appeared to be cut off but the full length is still within the cabinet. Very intact so far.

[Alex G. Bell]

Almost looks like a depth of field issue, the camera focused well on the back board (BAT) but the items closer to the camera are out of focus, so it appears. Might need multiple photos of the upper to get the front and back items in focus separately,

Perhaps, but flash at the proper angle to prevent reflections results in a much smaller aperture than natural light and much greater depth of field for that reason: "pinhole camera" effect.

[Alex G. Bell]

THAT is good information. I'll get better pictures and look at that large cable. It appeared to be cut off but the full length is still within the cabinet. Very intact so far.

Depending on what you want to do with it, 12-18" beyond the point where you want it to end would be sufficient to terminate it on conventional and readily available "66-type" insulation displacement connecting blocks.

If you are skillful with a soldering iron you could terminate two Amphenol 57-type 25-pair sockets or plugs.  These were also made with insulation displacement termination but without access to the terminating tool you would have to solder them. 

Once terminated in standard 25-pair sockets or plugs you could extend the cable or plug it onto a variety of different types of connecting devices equipped with mating plugs or sockets.  These 25 pair connectors have been used since the 1960s for terminating cables with multiples of 25 pairs.  The one in your swbd looks like a 50 pair.

[ramegoom]

More pictures. Better images. The main cable looks to be divided by trace fabric between a yellow bundle and a blue bundle. Also seems to be twisted pairs. This is getting interesting.

[Victor Laszlo]

I, too, thought that you might be posting an April Fools's message. The most painful thing for us collectors to observe is a board that has been eviscerated. There are so many boards on Ebay that are described as "original" but upon closer inspection, are missing the entire relay rack and wiring harness. It makes us weep to see such vandalism.

I am so happy to hear that our friendly protests have been taken to heart and that you will be keeping the board intact. Of all the ones Iv'e seen, it is in remarkably good condition. If I didn't already have a few, I would offer to buy it.

Getting it working in its original functionality will also allow you to do what you originally wanted to do: make it flash and ring. That's easy for us old telephone guys. Where are you located? Maybe one of us could send you a power unit and some notes on how to get it going again.

[Alex G. Bell]

More pictures. Better images. The main cable looks to be divided by trace fabric between a yellow bundle and a blue bundle. Also seems to be twisted pairs. This is getting interesting.

Much better, but I still need to see the markings on the face of the block, not just the edge. 

Some terminals, especially the ones for power, are individually designated.  Seeing what cable lead colors are connected to them will make it possible to determine which cable leads provide these power sources.

What appears to be yellow is actually orange.  These are called "binder groups".  Pairs consist of one "Ring" color and one "Tip" color.

The Ring colors are: BLue, ORange, GN (green), BRown, SLate i.e gray

The Tip colors are: WHite, RD (red), BK (black), YL (yellow, VIolet.

So the first pair is BL-WH.  The 25th pair is SL-VI.

Cables consisting of multiple binder groups (multiples of 25 pairs) have binders designated using the same color scheme used for the conductors.

[ramegoom]

Hope this tells the tale:

[ramegoom]

...Getting it working in its original functionality will also allow you to do what you originally wanted to do: make it flash and ring. That's easy for us old telephone guys. Where are you located? Maybe one of us could send you a power unit and some notes on how to get it going again.

I'm in northern Colorado, near Ft. Collins. This switchboard has a phone number on the dial of the phone. So I searched and found that this had originally been in a motel in Aurora, CO. The motel is still in business and still uses the same number, but the other two "sequential" numbers on the board are not in service. So they had three numbers assigned back then. Today, they only need the one. Good to know where it's original home was.

[Alex G. Bell]

Hope this tells the tale:

The photos at the left show the "factory side" of the blocks with textile insulated factory harness leads connected.   The photos at the right show the "installer side" of the blocks with vinyl insulated cable leads connected. 

You can see the T & R designations at the top of the STA L (station line circuits) and TRK (trunk circuit) connection terminals. 

Looking at the installer side of the STA L block the first 30 pairs of terminals have leads connected, starting with BL-WH (the first cable pair) and ending with SL-WH of the 2nd (OR-WH) binder (the 30th cable pair) on the 30th pair of terminals, just as one would expect.

There are 60 MISC terminals 1-60.  Every 8th terminal number is inked on the edge of the block but they are not individually designated to indicate their functions on the face of the block they way they are on some switchboards. 

I will look up the SD (schematic drawing) to see how the leads I see on the installer side of the MISC section correlate with what it shown on the SD.  That will happen over the weekend unless someone decides to take it on before I get to it.

[HarrySmith]

It is a work of art on the inside. All those wires run perfectly, terminated correctly and all laced up. Beautiful!

[Fabius]

I just acquired a switchboard, Model 551A. It is in remarkably good condition, and weighs probably 250 lbs. So, I want to place it in my game room as a display, and plan to "gut" it and put it on a severe diet.

My question: Is this wise to do? Will it hamper its appeal up the road? I can't imagine the unit actually being put back in operation.

Welcome to the forum.

That switchboard looks to be in original condition. Please do not cut it, add LEDs, etc. Sell it to someone who can appreciate it for the historical item it is. Use the money you get to buy one that's already gutted to use in your game room. Please persurve history, not destroy it.

[Alex G. Bell]

Welcome to the forum.

That switchboard looks to be in original condition. Please do not cut it, add LEDs, etc. Sell it to someone who can appreciate it for the historical item it is. Use the money you get to buy one that's already gutted to use in your game room. Please persurve history, not destroy it.

Very well said, Tom!

[ramegoom]

I mapped the cable pairs out. Now I need to know what pair does what. There's a blue laced bundle and an orange laced bundle, with identical pairs of wires:
Help!
What am I looking for? Need to attach two phones and a power supply. That's next.

[Alex G. Bell]

I mapped the cable pairs out. Now I need to know what pair does what. There's a blue laced bundle and an orange laced bundle, with identical pairs of wires:
Help!
What am I looking for? Need to attach two phones and a power supply. That's next.

You mapped them out incorrectly, ignoring or not understanding the color order I stated earlier. 

The first 5 pairs are BL, OR, GN, BR and SL paired with WH.  6-10 are paired with RD, 11-15 are paired with BK,  16-20 are paired with YL, 21-25 are paired with VI.

That's how I arrived at the previous statement that BL-WH in the first (BL-WH) binder is the first station jack and SL-WH in the second (OR-WH) binder is the 30th station jack. 

If you inspect the installer side of the STA L terminal blocks I believe you will see those colors on those terminals.