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Wiring 50AL Candlestick

Started by gands-antiques, January 19, 2018, 01:02:50 PM

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gands-antiques

I'm trying to wire a 50AL Candlestick

I have a 3 conductor harness and a 5 conductor harness and I believe a 4 conductor harness is required.  Can a 5 conductor harness be cut to make it a 4 conductor harness?

If possible, I would like to verify  the rack that came with the candlestick is correct.

Also, get wire to wire contacts.

I'm not sure what subset I will be using yet.

Thanks a lot,
Gary

poplar1

That is a rack from a 20-AL or 40-AL.

The 50-AL has 3 additional screw terminals  below the 5 shown above. And the 4-conductor dial cord connects to 4 additional terminals on the back of the rack.

The reason for so many terminals is that the 50-AL has all the connections (except for one end of the dial cord) made on the rack. There are no terminal blocks in the base of the phone, unlike the 51-AL or 151-AL.


"C'est pas une restauration, c'est une rénovation."--François Martin.

poplar1

50-AL rack:
"C'est pas une restauration, c'est une rénovation."--François Martin.

gands-antiques

Unfortunately the 3 racks I have appear to be like the 20-40 racks.

Is there a way one of my racks will work for a 50AL?

Thanks,
Gary

poplar1

You can probably make any of these work for a 50-AL, if you are willing to improvise a little (don't expect the terminals to be labeled the same). Both the 20-AL and the 50-AL have 3-contact hookswitches. You may want to make your own harness -- in any case, don't cut any wires since someone may want to use the harness you have for the correct model someday...

Here is a diagram from a crpf post
www.classicrotaryphones.com/forum/index.php?topic=13697.msg143399#msg143399

The terminals may be labeled differently. Also, if you run a wire (black in diagram) from the transmitter to BK on the dial, then you won't need the   BK/YY
                                   terminal shown in the diagram (just run the wire directly from transmitter to BK on dial).




"C'est pas une restauration, c'est une rénovation."--François Martin.

poplar1

So, you would connect the green wire from the subset to the green receiver wire. (You may want to create your own connector for this).
The white receiver wire connects to W on the dial.

The yellow wire from the subset would go directly to Y on the dial. 

The transmitter black wire would go from the transmitter directly to BK on the dial.

Red from subset would go to the hookswitch.
Other transmitter wire to hookswitch.
Jumper wire from hookswitch to BB on dial.
"C'est pas une restauration, c'est une rénovation."--François Martin.

poplar1

Corresponding hookswitch spring terminals on 50-AL and 20-AL racks:


                              50-AL         20-AL
longest spring:         YY                YY   

middle spring:          R                  R

short spring:            BB                W
"C'est pas une restauration, c'est une rénovation."--François Martin.

gands-antiques

Thanks Poplar,

Will you please tell me what the longest spring, middle spring and short spring are?

Gary
       
                            50-AL         20-AL
longest spring:         YY                YY   

middle spring:          R                  R

short spring:            BB                W

poplar1

I am talking about the "contacts" on the rack...when you hang up, the hook with a round, black insulator pushes against the long spring. It is labeled "YY" (stamped into the metal rack).

The  terminal above that is labeled "R."

The terminal above that is labeled "W" (stamped in the metal). This corresponds to BB on a 50-AL rack and to BB in the diagram above.

"C'est pas une restauration, c'est une rénovation."--François Martin.

gands-antiques

Thanks got it.  I'm going to try putting all of this together tomorrow.

In the meantime, a friend of mine is looking for a 50AL rack that has the extra terminals.

Thanks,
Gary

poplar1

The 20AL, 50AL, 51AL, as well as a B1/D1 with 3-conductor mounting cord (102) are all sidetone. Thus, the easiest way to connect them is to a sidetone subset such as 534A, 295A, 334A, 584A. The advantage of the sidetone subset is that -- unlike the anti-sidetone subset --  you can connect multiple phones to one sidetone subset. Also, you can use an anti-sidetone phone (151-AL, 202, 211) with a sidetone subset by just taping and storing the black wire in the mounting cord from the phone to the subset.

If you don't have a sidetone subset, then there are posts on CRPF for using an anti-sidetone subset (634A, 684A, etc.) or the base of a 302 telephone set. Also for using a network subset (685A) or just the 425-type network from a 500 set.

Here is the preferred method for connecting a sidetone desk stand or hand telephone set to an anti-sidetone subset. This appears only in the WR (Wartime Restrictions) BSPs:

http://www.classicrotaryphones.com/forum/index.php?topic=8785.msg117918#msg117918

This is preferable to the more commonly found diagram which shows connecting the black condenser wire directly to L2-Y. That wiring method should only be used on a line where there are no extensions, because it loads the line.
"C'est pas une restauration, c'est une rénovation."--François Martin.

poplar1

Without changing any wiring in the phone, connect the cord from the phone to the 634A/684A/302 base as follows:

Yellow to GN on the induction coil.
Red to L2/Y on the induction coil.
Green to BK (along with the black condenser lead). (Use spare terminal GND for both wires if using a 302 base.)

IN THE SUBSET:
The red incoming line should be connected to C---and not L1.
The red ringer wire should connect to C--and not L1.
ALSO MOVE RED CAPACITOR WIRE FROM C TO L1.

This provides a sidetone circuit.

Reference:
Bell System Practices
Station Installation and Maintenance
WR-C63.373
Issue 1, 9-30-42
AT&T Co

www.classicrotaryphones.com/forum/index.php?topic=8785.0
"C'est pas une restauration, c'est une rénovation."--François Martin.

gands-antiques


TelePlay

poplar1,

What was the purpose of the optional varistor in the subset? What did it do or when was it needed?

poplar1

#14
Quote from: TelePlay on January 20, 2018, 03:06:15 PM
poplar1,

What was the purpose of the optional varistor in the subset? What did it do or when was it needed?

I would have to look for the BSP, but I am guessing it is shown for a head receiver, such as on a 52AB desk stand. It reduces the clicks (voltage spikes) in the receiver. All 500 sets are equipped with a varistor on the back of the U1/U3 receiver unit.
"C'est pas une restauration, c'est une rénovation."--François Martin.