looking for information on modified T-adaptors for Princess with lighted dial

[RotoTech99]

Dear Forum:

I'm looking for a topic I think I saw on CRPF regarding modifying a T-adaptors to use with a 2012A/C transformer,  and a Princess or Trimline type set when the WE 338 adaptor isn't available.

I thought I saw the posting,  but since it's been sometime since I have seen it... Please,  if someone has this information,  and any diagrams,  I would appreciate please either reposting it,  or send me a PM in regards to it.

Thank you, 
RotoTech99

[TelePlay]

I'm looking for a topic I think I saw on CRPF regarding modifying a T-adaptors to use with a 2012A/C transformer,  and a Princess or Trimline type set when the WE 338 adaptor isn't available.

I thought I saw the posting,  but since it's been sometime since I have seen it... Please,  if someone has this information,  and any diagrams,  I would appreciate please either reposting it,  or send me a PM in regards to it.

     Regular Member Post


Use these words in the forum search function:  princess transformer adapter

I got 15 hits and more than a few of the 15 discussed ways to attach a transformer to a line in using a "junction/splitter/adapter" device which then allows one wire from the device to the phone that provides both L1/L2 and power for the lamp. There are more than one way to do this including the "official" WE way

     https://www.telephonecollectors.info/index.php/browse/wiring-diagrams-technical-library/western-electric-1/princess/2212-princess-telephones-2012-tl

[RotoTech99]

Dear Teleplay:

Thank you, I have that diagram on  my computer.

The one I'm looking for modifies a standard t-adaptor that has 4 contacts per side. I"ve seen the diagram for it but for the life of me, I cant find it now.. I know it involves moving the yellow and black leads inside the adaptor, but how specifically I'm not sure; it avoids cross circuiting or something to that affect.

I do recall that if you're going to use the dial light transformer for the Signature Princess on a traditional Trimline or Princess, you need to replace the existing plug that has the adaptor's power coming from the two center contacts, and replace it with a 4 pin RJ11 plug, and make the transformer leads so they go to the contacts in the plug normally associated with the black and yellow wires, and crimp it on.

Leave room enough to crimp onto the outer jacket.

I found out early on that if you use the Signature Princess adaptor as supplied with a older Trimline, it will melt a flex circuit in the handset. I was using a 338A adaptor inn place of the one supplied with the Signature Princess transformer, so nothing worse occurred.

I'll keep me eyes open for that info I asked for as I know it's still "out someplace", but precisely where I"m not sure.

RotoTech99

[RB]

Do you have the schematic for the phone you are using?
That would tell us what you need for a transformer...
and how to wire it.

[poplar1]

The 338A T-adapter bridges the yellow and black of each side together, but does not back feed that pair into the wall jack. So, using the 2012C transformer with the built in modular adapter on the transformer, either side of the adapter can be used for the phone (green, red, yellow, black) or for the transformer (yellow and black).


2012C Transformer if you don't have a 338A adapter:


You can just modify a traditional T-adapter (267A).

Leave the yellow and black connected to both sides of the adapter, but cut them where they go into the plug that goes into the wall jack.

If your 2012C has the added modular jack mounted on the transformer, then just use a 4-conductor modular cord from the transformer to the 267A adapter (either side). Plug the other 4-conductor cord from the phone to the other side of the adapter.

If the 2012C transformer does not have the "piggyback" modular adapter, then you will need a 4-conductor half-modular cord (modular to spade tip). Connect the yellow and black spade-tip wires to the 2 terminals on the transformer. Plug the other end of this cord into either side of the modified 267A adapter.

[poplar1]

Signature Princess transformer:

The one-pair cord on the Signature transformer, as you pointed out, uses only the 1st (inner) pair, or red and green. So the adapters originally supplied for the Signature are different: they are usually labeled POWER and PHONE or something like that. You have to plug the Signature transformer into the correct side. This adapter has red and green (only) on the transformer side, and the red and green from that side go to the yellow and black positions (2nd pair) on the "phone" side.

Instead of changing the plug on the Signature adapter, you can just modify a traditional T-adapter:
Connect the red and green (only) of the side used for power to the yellow and black of the phone side. Cut the other wires off on the power side. Make sure the yellow and black of the phone side of the adapter are no longer connected to the plug portion of the adapter (the part that plugs into the wall jack).


Panasonic used to supply an adapter with their 2-line phones that was required if your lines were on 2 separate wall jacks (RJ11C) rather than both lines on one jack (RJ14C). You plugged the 2-line phone into the side of the adapter marked phone. Then you ran a standard modular cord from the other side of the adapter to the 2nd wall jack. If you can find a similar adapter --- usually marked "L1/L2" on one side, and "L2" on the other, then you can use this with a Signature transformer without modification (not for membrane Trimlines, though, as you pointed out). Suttle and AT&T also made that type adapter--don't remember if they called it 267B or 267C or something else.

[poplar1]

Here is another method: the dial tone and transformer are hardwired to the inside terminals of a new biscuit jack. Then, the modular Princess plugs into the new biscuit jack. See the picture from Ebay seller ellensbrother.

https://www.ebay.com/itm/143017436015

Dial tone to R and GN terminals inside new biscuit jack. (shown here with a white modular to spade cord)
2012C transformer to Y and BK terminals inside new biscuit jack (shown here with beige inside wire)

Princess plugs into the biscuit jack (not the wall jack)

[TelePlay]

Here is another method: the dial tone and transformer are hardwired to the inside terminals of a new biscuit jack. Then, the modular Princess plugs into the new biscuit jack. See the picture from Ebay seller ellensbrother.

https://www.ebay.com/itm/143017436015

Dial tone to R and GN terminals inside new biscuit jack. (shown here with a white modular to spade cord)
2012C transformer to Y and BK terminals inside new biscuit jack (shown here with beige inside wire)

Princess plugs into the biscuit jack (not the wall jack)

     Regular Member Post

That is the most common method I have seen used including eBay phones for sale, used by members on the forum in their posts and the exact way I have configured the power and line connections to light a Princess. Everything from the modular adapter to the wall (line and power) is easily hidden on the floor behind the phone stand with only the line cord from the adapter to the phone showing. And those modular adapters are currently available from several sources for under $1 each.

Line cord from the wall is attached to red and green in the adapter and the low voltage power is attached to yellow and black.

[RotoTech99]

Dear Poplar 1:

I suppose the biscuit jack is a pretty good idea,  and I'm glad that there are those who can use that with their Princess phone.

I prefer to go with the Princess & dial light transformer connected via a modular jack adaptor that allows connection of both to the phone line.

Thank you for the info.

RotoTech99

[poplar1]

See 267A4 diagram here, as manufactured:
If possible, remove the black and yellow wires going to 2 and 5 at the top of the picture.

[HarrySmith]

The biscuit is how I did my 10 buttton NE Contessa. Easy to do and works well. See old for sale listing here: http://www.classicrotaryphones.com/forum/index.php?topic=20970.0

[TelePlay]

     Regular Member Post

The splitter or "T-adapter" is a "neat fix" but one that is totally modular.

The biscuit can be any combination of wiring and the biscuit mod jack end used toward the phone or toward the wall using full and half modular cords and spade lug cords on the biscuit terminals when needed.

poplar1 had it right in saying all you have to do on a "T-adapter" is remove the yellow and black wires from the plug side of the "T" that goes into the wall phone jack, carefully pulling them out of the plug end of the "T."

[RotoTech99]

Dear Teleplay:

I got my T-adaptors today,  but they turned out to be the 4 contacts in the plug,  and 4 conductors to each jack,  so I had to use a different conversion a friend learned from Steve Hilsz, then showed me how to do it.

The conversion is to pop up the #1 and #4 contacts in the plug, then slip the black and yellow conductors out from under each one,  and put the contact back in place.

Aside from the holes where the contact pierced them,  the black and yellow wires are intact,  and only connected at the jacks.

the prongs holding the t adaptor together popped off when I opened it,  so I super glue gelled it back together.

Attached is a, photo of the assembled modified T-adaptors with the 4 holes where the prongs  holding the adaptor together were visible; I use that as a way to identify the adaptors I modified.

when I have the next one ready to modify,  I'll include a inside view.

RotoTech99

[Scott]

This is how I have made t-adapters for myself in the past. I try to find adapters with the four prongs in the corners holding the sides together instead of the sides being glued or sealed together. I haven't found a good way to easily depress all four prongs at the same time to get the sides apart but with a lot of patience it can be done. Then you have to decided which port will be for the line and which for power. Next make the cuts to the appropriate wires. I then solder them together and finish with heat shrink tubing. I have only done this for my own use so far. I have never supplied this set up with telephones I've sold. Like others, I have been contemplating going to the biscuit idea for ease of connect ability. I hope the attached photos help. All the best.

Scott K.

[RotoTech99]

Dear Scott:

As I mentioned in my post,  in my case with the adaptors I'm using,  it's easier to pop up the contacts and slip the wire out from under them.

As to the prongs,  I've tried numerous times to keep from snapping them off,  so I thought "why not use that to identify them as modified? " I think it's a good use for the inadvertent mishap.

RotoTech99