Western Electric 50AL versus 51AL

[davidbholcomb]

I just purchased my first 50AL CS with a 2AA dial and being a novice I think the phone may have been tinkered with. Below is a picture of the inside of the base. I understand that the difference between a 50AL and 51AL is a terminal block in the base. Does my 50AL  have the terminal block? If not, I would love to see an image of one. I am trying to figure out the whole wiring thing. I love when the old phones work and at this point this one is not. I think it may be wired wrong.

[poplar1]

The 50AL has all of the connections made on the rack where the hookswitch is, other than the other end of the dial cord, which has 4 conductors. The dial cord connects on the side opposite from the hookswitch. There is no separate terminal block in the base. The hookswitch has 3 leaves. The cord to the subset has 3 conductors (sidetone).

The 51AL has one terminal block as in the photo and uses a 3-conductor wiring harness from the base to the rack. Like the 50AL, the hookswitch has 3 leaves and the cord to the subset has 3 conductors.

The 151AL has two terminal blocks in the base, a 5-conductor wiring harness, and a 4-leaf hookswitch. The 5-conductor harness is usually like the one in the photo: a cloth covered 3-conductor cord from a 51AL that has the extra two wires wrapped around the cloth-covered cord. The cord to the subset has 4 conductors (anti-sidetone.)

Is your phone is marked 50AL on the lug holder (perch)?   Does it have a 3-leaf hookswitch and dial connections marked on the opposite side of the rack? If so, you apparently have a phone that is part 50AL, part 51AL (or 151AL with a missing terminal block), and part 151AL (the dial harness).

The dial is also not wired correctly. It has the contacts of a 4H or 2H, not a 2A. The dial you have can be used, but the BB and R terminals are strapped together.

[davidbholcomb]

Thanks David for taking the time to respond. This novice truly appreciates the time and effort. Well it appears that my phone has issues. Yes it is marked 50AL on the perch. It seems to have the 51AL terminal block. I believe it has a 3 leaf hookswitch, but I am not sure, I have attached more photos. Can this phone be salvaged into a 50AL phone? It appears that the terminal block can be taken off. Is it a matter of just buying new cords to wire it as a 50AL?

Is the dial not a 2AA? Has it been made to look different than what it truly is? You mention "The dial you have can be used, but the BB and R terminals are strapped together." I am not sure what you mean by this.

Thanks again for the help.

The 50AL has all of the connections made on the rack where the hookswitch is, other than the other end of the dial cord, which has 4 conductors. The dial cord connects on the side opposite from the hookswitch. There is no separate terminal block in the base. The hookswitch has 3 leaves. The cord to the subset has 3 conductors (sidetone).

The 51AL has one terminal block as in the photo and uses a 3-conductor wiring harness from the base to the rack. Like the 50AL, the hookswitch has 3 leaves and the cord to the subset has 3 conductors.

The 151AL has two terminal blocks in the base, a 5-conductor wiring harness, and a 4-leaf hookswitch. The 5-conductor harness is usually like the one in the photo: a cloth covered 3-conductor cord from a 51AL that has the extra two wires wrapped around the cloth-covered cord. The cord to the subset has 4 conductors (anti-sidetone.)

Is your phone is marked 50AL on the lug holder (perch)?   Does it have a 3-leaf hookswitch and dial connections marked on the opposite side of the rack? If so, you apparently have a phone that is part 50AL, part 51AL (or 151AL with a missing terminal block), and part 151AL (the dial harness).

The dial is also not wired correctly. It has the contacts of a 4H or 2H, not a 2A. The dial you have can be used, but the BB and R terminals are strapped together.

[poplar1]

That is a hookswitch from a 50AL. The 4 wires from the dial connect on the side opposite from the hookswitch. The terminals are marked Y, BK, BB and W, the same as the dial terminals. You will have to remove the brass strap that is shorting Y and BK terminals (shown in the photo.) EDIT: Also remove  the strap (short wire) between BB and W on the back side of the hookswitch. The straps was were there because this phone originally did not have a dial. (The dial Y and BK contacts will now short the Y and BK terminals on the back of the hookswitch, except that the dial contacts will open and close for example 7 times if a 7 is dialed. The dial BB and W dial contacts will now open to open the receiver so you don't hear the clicks when the dial is pulsing.)

Since the dial has the 2H contacts instead of the 2A, you will need to run a piece of wire from BB on the dial to R on the dial. (I don't know if the strap you are removing from the rack will fit; if so, you can use that.) Then you will need 4 conductors from Y, BK, BB and W on the dial to the terminals on the back of the hookswitch.

You won't need the brown terminal block. Both the receiver cord and cord to the subset will terminate on the rack (where the hookswitch is).

Next, you will need a sidetone subset such as 295A (wood), 534A (steel) or 584A (Bakelite).
If the cords are good, they are OK. You need two conductors to the receiver and three conductors to the subset (bell box).

[davidbholcomb]

Thanks again David for the reply. Sounds fantastic that I can return this to its original condition. I am still a little confused by one thing. You mention "Since the dial has the 2H contacts instead of the 2A, you will need to run a piece of wire from BB on the dial to R on the dial." I can not find "R" on the dial. I have attached a picture with a close up. It does have the Y, BK, BB and W contacts along with a 2nd W contact.

[poplar1]

The strap on the dial needs to go from BB to the terminal just to the right of it, currently marked W.

The fact that this terminal has not been restamped "R" in vermilion ink shows that the swapping of the contacts was done by someone other than a Western Electric shop. WE would have renamed the terminal and renamed the finger stop as well (from 2A to 2H).

The strap makes a 2H, 4H, 5H or 6A function as a 2A.

[Phonesrfun]

With the handset-style switch on the back of the 2AA dial, the W on the far right of the row of terminals is now R.  The second W terminal in the upper left of the picture is now the real W.

Usually, when a dial was modified to be an H model, the W embossed in the metal body of the dial was struck out and an R stamped in itsplace.

No matter, it will all work.

[davidbholcomb]

Thank you David and Bill for the replies. I am truly excited about being able to return this phone back to its original shape. If you can bare with me for just one more question. After reading all, the dial as is, is truly a 2AA dial, not modified. But the way the phone was wired when I found it the dial should have had its marks changed. Is it a true statement that the 50AL would have come with a 2AA dial?

I guess someone in the past tried to make this phone an anti-sidetone phone by making it similar to a 151AL but not doing a very good job.

[HowardPgh]

I think that strap on the hook switchook terminals make it act like a 51AL switch.  In my opinion a 51AL is a simpler phone to wire as most of the connections are in the base rather than in the switchook column. In the 51AL the only connections is a three lead switch cord and the transmitter, the receiver and subset cord connections are in the base, hence the need for that little terminal block..
Howard

PS: Look at the older BSPs for the Machine Switching Stations, there are schematics and cording diagrams, it is very detailed.(and helpful) I learned a lot about these desk stands.

[poplar1]

Thank you David and Bill for the replies. I am truly excited about being able to return this phone back to its original shape. If you can bare with me for just one more question. After reading all, the dial as is, is truly a 2AA dial, not modified. But the way the phone was wired when I found it the dial should have had its marks changed. Is it a true statement that the 50AL would have come with a 2AA dial?

I guess someone in the past tried to make this phone an anti-sidetone phone by making it similar to a 151AL but not doing a very good job.

A 2A dial has only 4 terminals, their names  stamped in the metal left to right Y BK BB W. The 2H has the contacts as on your dial and the additional W contact next to the governor, and the stamped names Y BK BB and R.

As Bill pointed out, the 2H was used on Hand Telephone Sets using an A1, B1, C1, D1, E4, etc. Hand Set Mountings. The 50AL used a 2A (2AA all figures, 2AB figures and letters, 2AE figures + J, M, R and W for dialing to non-dial central offices that had party lines).

The 2A dial will work with 50AL, 51AL, or 151AL. The 2H, 4H, 5H and 6A dial will also work on all 3 models by strapping BB and R. 2H dials probably did not exist before 1927. The 50AL and later 51ALs were made between 1919 or 1920 and 1930. No 151ALs were made "new." They are all conversions from earlier desk stand telephones.

[davidbholcomb]

Thanks all for the replies and baring with me till I understood all. It has been a big help