WE 20-T candlestick 269W transmitter question

[Witty]

I am cleaning and trying to restore this candlestick back to original condition. I can not find a wiring diagram for it. The 20-T also has the smaller 269W transmitter. I understand these units were intercom units?
I was wondering if maybe some collector might have a similar one and could send me a picture of the internal parts of the transmitter.
I am especially curious about what piece is missing inside the transmitter cup.
I've provided a few pics for reference.
Thanks for any information.

[TelePlay]

Here's an old topic for reference:

http://www.classicrotaryphones.com/forum/index.php?topic=6951.0


Could use something like a "302" F1 transmitter sitting on top of the two contacts (mounts). No idea how the center contact is made with the transmitter electrical contacts, unless those two "mounts" are offset - hard to tell by the photo angle. Someone might know better, or have images of the complete transmitter.

[Witty]

Thanks for the link. It seems his also has two cables into the transmitter. I was curious about that.
I've added a few more pics. It looks like a round transmitter piece slid between the two curved posts inside the cup. It looks like this was some kind of a later modification, but I really have no clue.
Hopefully someone will provide a pic of the inside.

[TelePlay]

It looks like a round transmitter piece slid between the two curved posts inside the cup.

Keep in mind that a wire is connected to each curved post so whatever transmitter element is proper, one of the curved posts must contact one side of the element and the other curved post must contact the other side of the element.

The F1 would not do that unless there was a special bakelite/plastic adapter the would hold an F1 type element and properly connect the F1 contacts to the curved posts.

[tom.adams1]

Here you go on photos of the transmitter.

[Witty]

Thanks Tom!
The structure on yours looks like it is similar to the small 273W transmitter used in the WE 327 intercom boxes. Maybe that's the difference in the use of the 273 and 269, one for the 327 box unit and one for the 2O-T candlestick.
My faceplate does not have the two screw ears to attach the spring clips inside.
I feel like mine is a later modification to attach a different kind of transmitter element. The top edges of the two curved posts are only 1/8" from touching the inside of the faceplate, so whatever element was used it must have sunk down below those top edges. I'll probably never know what kind of element that would have been, unless someone happens to have a similar one.
I've provided a closeup with the faceplate on, and the mouthpiece removed.

[Witty]

A better angle.

[countryman]

There is definitely no room left to put any type of carbon transmitter inside. I agree, an "interestingly" made adapter to attach "something", probably on the outside with the mouthpiece removed? My first thought was a bayonet lamp socket, but then it lacks the bottom contact...

[TelePlay]

I will retract everything I said about the possibility of using an F1 element in this transmitter. There are 2 WE Interphone documents in the TCI Library (links below) that show many versions of Interphone systems. Those that show a Desk Set (candlestick) show parts, by name, that make up the Desk Stand and they include a WE 302-W transmitter, not a transmitter from a 302 telephone, an F1.

WE Interphones and Accessories 1915

INTERPHONES - From 1918 WE Electrical Supply Year Book Tl

These desk set Interphones date back to the early 1900s. I can not find a WE BSP or Catalog that shows one of these small, different transmitter elements. Doesn't mean it doesn't exist, means after an hour of searching a lot of files and sites that I could not find one.

Found a lot of references to the WE 20-T Desk Stand indicating the use of a 302-W transmitter but nothing about the element itself. A bad transmitter was probably replaced in total, not "repaired" in the field. Did find this one reference to the 269W transmitter unit. Not sure if the 302-W was inside the 269W or if the unit itself was marked 302W on the faceplate.





Looking at the images posted here, I can see where those posted by tom.adams1 might be correct. a very flat, small carbon transmitter unit mounted to the faceplate by use of two rubber tipped fingers.

Looking at the images, the tom.adams1 back shows two contact points, one of which is insulated from the case (white circle). Assuming one of the case mounting holes aligns the back so that the two curved posts each contact one of the transmitter contacts, that would work. The tom.adams1 images might have been for a 269W that was hard wired rather than using the curved post design with one wire attached to each curved post.



All this is guesswork on my part. Maybe someone with a room full of phones has one of these Interphone sticks and would be willing to take the transmitter apart and post images.

======

On the lighter side, I did find that one could buy an Indian motorcycle from WE in 1912.

[Witty]

Some interesting information there.
I wanted to point out your red lines don't point to the same references. On the left they point to the back of the revits that hold the banana tag onto the face plate. The right end of the red lines point to the screw ears of the face plate that the spring clips are screwed to, which my faceplate doesn't have.
I've seen the Indian motorcycle items in a couple of their catalogs, and even posted a photo of one in the old photos section at one time awhile back. If anyone still had one of those it would be worth a fortune today!
Thanks for the info.

[TelePlay]

Yes, you are right, thought I was looking at threaded mounting holes and forgot about the riveted tag. Spacing did look good anyway.

It could be that that small carbon capsule transmitter is still correct except held in place by only contact with the curved posts, being limited space no need for the 2 rubber tipped fingers. Pressed together the same way transmitter elements are held in place in a 302 or 500 handset.

The "finger" image seems to be a hard wired, to the screws, electrical connection so would need the fingers to hold it in place. The curved posts would eliminate the need for the fingers.

[tom.adams1]

I'm probably wrong Ken, but it looks to me like your spring tabs were cut off. I took mine back apart and lined up with yours and it appears to me I can see where the tabs were located. This makes me believe your part inside the cup is an add on, not factory.

[TelePlay]

This makes me believe your part inside the cup is an add on, not factory.

That curved post piece looks too complex and expensive to be a one off home made contraption. It could have been a factory or refurb company "improvement."

From the front view of your transmitter, Tom, it does look like a carbon capsule transmitter with possible a rubber washer between the diaphragm and the faceplate to reduce hand held transmitted noise. The rubber washer is on the back, under the spring fingers, and I suspect (like all other 200 series WE carbon capsule transmitters) it had a rubber washer on both sides.

It's unfortunate that your transmitter can't be placed into Ken's faceplate to see if the curved posts match up with the 2 contact points on your transmitter and the posts hold it into place (doesn't rattle and the case closes).

It's also probably the reason why the small transmitter is missing, nothing holding it in place when the back with the 2 curved posts was removed, it simply fell out, or was taken out for use elsewhere.

[Witty]

Tom,
I agree the tabs were probably cut off. Looking closer under a magnifying glass it looks like they were milled off very clean then nickel plated over consistent with the rest of the plating of that part.
I also agree the internal parts look too complex and probably created in a fab shop somewhere.
It's a beautiful phone and I was hoping to get it back together in working order but I doubt I'll ever find the right transmitter element that was in it.
The mouthpiece is original WE in excellent condition as is the receiver. The receiver is in the best condition of any others I have. I've noticed the internal magnet bars are not painted black like all the other WE I have and have exposed revits at the top.
It'll be disappointing having it all together knowing it's missing an important part. Ill take some pics when back together with replaced cables.

[tom.adams1]

Ken, that silver magnet element is one used in the Western Electric 143 receivers, it should have smaller size coils in it but still 75 ohms.  I'm posting a couple photos of my WE 20AT - 20AS Intercom Desk Stand and it is near mint.  It is interesting that it is stamped 20AT on the perch and has a paper label inside the base that says 20AS, one is 4 button and the other 8 button. Also note the smaller size transmitter. Note that the 302W transmitter inside element is different than the 269W.