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Need help getting a KTAS DO 08 type wall phone with added dial to work - wiring help needed

Started by Lee58, August 20, 2017, 10:39:03 PM

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Lee58

The only way I get dial tone is by attaching red and green wire to top terminals 2 and 3 but with that phone does not dial or hang up. This may be useless info but I would not know that.

poplar1

Quote from: Lee58 on August 22, 2017, 02:01:18 PM
The only way I get dial tone is by attaching red and green wire to top terminals 2 and 3 but with that phone does not dial or hang up. This may be useless info but I would not know that.

You are probably connecting the line directly to the receiver on 2 and 3, thus bypassing the dial, hookswitch, and induction coil. This   would be the same as removing the 4 wires of the handset cord from the phone, and connecting the red and green line wires to the 2 wires going to the receiver, without using any of the other parts.

It just means that the receiver is good, and at least 2 wires in the handset cord are good.
"C'est pas une restauration, c'est une rénovation."--François Martin.

Lee58

  I knew it was not correct but thx for the good info. Gives me a better understanding

TelePlay

Just to organize all of the images into one, These show the phone as opened, the terminal strip with yellow numbers and the dial terminal with red "D" numbers.

I think if everyone used this composite image with the terminal numbers show, it should make figuring out or talking about the wiring consistent from reply to reply from this point one. With the dial next to the terminal strip, it is evident where the 3 plastic wires came from. And as noted above, the Brown/Black wire from D2 is connected to one of the cloth leads attached to the condenser.

Only thing left to do is figure out the wiring of the rest of the phone.

TelePlay

Here is a video of the dial in operation. It shows the shunt springs on the right and the pulse springs on the left. Not known which terminals are associated with which operation.

https://youtu.be/uMTPIEQ2kf8

dsk

Generally KTAS (Copenhagen telephone company) got their last exchange automatic in 1978!
It is not easy to say how the original circuit was before the dial was put in to your phone, but:
Generally these telephones had simple voice circuit.  The induction coil had 2 separate windings, the highest ohmic value was the secondary, and the only components connected to this winding was the receiver, no dial, no hookswitch here. The primary was in series with a typical European "less good" transmitter. This transmitter was usually shunted (bridged) with a resistor or coil to avoid a false on-hook signal.  The ringer, transmitter and resistor were connected to L2 and the hookswitch connected to L1.  The hookswitch did disconnect the ringer circuit and connected the transmitter circuit when you went off hook. The capacitor could be a part of this switching from ringer to something else. (capacitor between 1/2 to 2 microfarad)  The dial had 4 wires (at your picture from left, pulse, common and shorting R and Y. The 4th of these where used for counter function if installed.

As you see pretty different from North American phones, but should work OK.

dsk

Alex G. Bell

Quote from: TelePlay on August 23, 2017, 12:57:59 PM
Here is a video of the dial in operation. It shows the shunt springs on the right and the pulse springs on the left. Not known which terminals are associated with which operation.

https://youtu.be/uMTPIEQ2kf8
With a single sharp (well focused) photo of the complete dial contact assembly, not a bunch of separate partial closeups, it should be possible to determine which screw terminal is related to which contact function by following the layers of contact springs around from the contact tips to the screws, like on an AE dial, something which is impossible (but unnecessary) with WECo #2, 4 & 5 dials because of the point-point wiring between terminal screws and contact springs on the underside of the contact assembly.

Also, the interconnections probably are no different from those of a desk set of the same vintage.  I have a few European sets including a Danish one which uses a Danish version of the British dial.  This Danish set appears to contain identical internal components to this wall set except it also has a charge register and multi-contact terminal block at the wall.  Looks the same as this:
http://www.classicrotaryphones.com/forum/index.php?topic=4640.msg101596#msg101596
except for the Danish dial face and 11-terminals.

The dial mechanism appears to be the same.  I have checked continuity between contacts and terminals.  Naming the screws from left to right with the terminals at the bottom I found the following connections:

1 connects to the inner (R) dial pulse contact.

2 is a common terminal connecting to one contact each on the 3 contact sets: the outer (L) DP contact, the outer (R) contact of the inner shunt set and the inner (L) contact of the outer shunt contact set.

3 connects to the inner (L) of the inner (L) contact set.

4 connects to the outer (R) contact of the outer (R) contact set.

The cradle switch has the same contact configuration and 3 of the 4 wires have the same colors.  I began reverse engineering a wiring diagram some time back but did not complete it.   The terminal strip in my phone has 11 rather than 8 terminals, at least partly because of the call meter, with links between 3-4 and 5-6 instead of 2-3 and 4-5.  I will try to finish the diagram I was creating and will post it when I have.





dsk


You are right!

From this thread: http://www.classicrotaryphones.com/forum/index.php?topic=14941.0
The diagram and picture of the dial shows how it was used.


The Red wire is here used for the counter system, and the yellow for shunting, but I see no great difference of using it as in the one in this thread.  The left Blue is the pulse contact, the Black is common, and the 2 others are shunting to common when the dial is out of rest position.


dsk

Alex G. Bell

Quote from: dsk on August 27, 2017, 02:50:45 PM
You are right!

From this thread: http://www.classicrotaryphones.com/forum/index.php?topic=14941.0
The diagram and picture of the dial shows how it was used.

The Red wire is here used for the counter system, and the yellow for shunting, but I see no great difference of using it as in the one in this thread.  The left Blue is the pulse contact, the Black is common, and the 2 others are shunting to common when the dial is out of rest position.


dsk
Yes, the leads are in the same color order on my dial too.  Thanks for the diagram.  I will reconcile it with what I reverse engineered so far to see if they match.  I can see though that the phone discussed in this topic has 4 cradle switch contact springs: a single break and double make with a common spring between them, as does mine, but the diagram shows two breaks and a triple make.  So this does not quite match the subject phone, though it probably is a big step in the right direction.  Is there a higher resolution version available?

BTW if that photo is of your phone you probably should unwind the YL lead from around the RD lead to remove the tension.

dsk

Sorry, not my phone, and pictures from the thread mentioned. They may be better there.


I have tried to translate, and simplify the diagram to how it probably could be in the telephone in this thread. 


dsk

dsk

I may only answer for my own, and I would have liked to help more, but danish telephones are slightly different from Norwegian phones, and I have had an accident so I have had periods I have been pretty drugged down when my pain has been at top. (Thank you to all the medical personnel who has been involved !)  I do not want to believe the disturbing questions has been other than curiosity, and the answers has been of good will. Still I really hope the persons mentioned reads this, and learns.  I will probably be able to follow up the Danish phone better during the next days if I can help. 

Regards
dsk

TelePlay

Having worked with Lee trying to figure out what is wired to what and where in her KTAS phone, we've come up with this first version wiring diagram.

There are 7 wires going under and/or coming out of the plate (which she has been unable to remove because the screws are frozen tight).

The question is which above plate wire goes where under the plate. Lee had ordered a 11 function multi-meter and clip leads and when they arrives, dsk should be able to walk her through the process of finding out where each of the 7 wires go by checking continuity and capacitance.

Another question is the handset connections. The colors seem to be as stated on the original wiring diagram that was used as the starting point for the attached diagram. Terminals 1, 2, 3 and 7 seem to be green/black, green/white or yellow/ green/brown and green/white or yellow. A little Wool-lite on a cue tip could clean up the spots to see which is which (I assume they are as stated on the original diagram as black/yellow/brown/white). dsk may be able to have her test the wired to see where they go in the handset or even open up the handset to make sure the handset connections are correct.

The dial image seems to show D2 as common, D1 pulse and D3 shunt. D4 is not used, no meter in the phone.

I'll let the more learned phone members evaluate the wiring diagram to see if it looks correct, is correct or needs adjustment (diagram or phone). I do not have the phone so all of this was created by many PMs and emails between Lee and me over the past 10 days.

The colors are not the same as the wires. The wires going into or coming out of the tunnel are 1)red, 2) red, 3) white, 4) black, 5) black, 6) yellow and 7) green (the D2 dial terminal brown/black connected to a green cloth wire) if that helps. I left a white strip on the diagram which will allow them to be cross connected when we know where they go.

Lee should be getting her meter by the end of the week, Monday at the latest.

Through one of the links posted above, I found my way to this link which is a very good Maintenance Manual for this dial.

     http://www.britishtelephones.com/tel%20auto%20b5126.htm

TelePlay

Lee was able to loosen the screws on the plate so she now knows what is underneath.

I've included the image she sent me and also attached the updated and complete wiring diagram according to what she told me. So, the diagram is complete, hopefully accurate and provides enough information for those who can read these circuits with what may be wrong.

Seems the dial center terminal (D2) is attached to the coil, which also has two black wires and a white wire.

All she needs now is help from the experts to read this circuit and see if anything is wrong with it.


TelePlay

dsk looked at the first guess schematic and made the following corrections (dotted lines by dsk) and suggest the text below in order received in PMs from dsk:

=======================

Could you pleas look at the possible switch at the hook switch, and the mix of 2 wires among the 7 ones?

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You have done a great job, I have been looking at the drawing, compared with the known schematics from the table top with counter.

That drawing states to be valid for tabletop and wall models, but wall models should not have the "rosett" (wall terminal block?)

I had to base it on some Ideas;
1: The receiver is only connected directly to the secondary windings.
2: The handset wires is configured with the 2 receiver terminals in the "middle" so the handset wires would be from top Transmitter, Recever x2, Transmitter (direct to one of the lines)
I had to guess about the tube capacitor to actually be a resistor, or coil shunting the transmitter. (less important)

If that is right 2 black wires has been switched among the 7 to the bottom mount.
Some wires has switch address at the hook switch.

----------------

OOPS
Switxhing green and brown on the dial may be the solution of the dialing problem, not sure, but it is easy to test, ans reverse the switch back if its not helping.
dsk

==============================

Once we get the wiring correct and the phone working, I will re-do the wiring diagram to match the working circuit (re-run the traces for neatness)


=========================================================

EDIT: The wiring diagram below has been re-drawn and that version is below at this link:

     http://www.classicrotaryphones.com/forum/index.php?topic=18730.msg193092#msg193092