Ringer problem on Northern Telecom 554 wall phone

[axil]

Yup no prob there thx. Not sure if I should start a new thread but I am having an issue with the ringer on a Northern Telecom 554 wall phone and was wondering if this is common with these with the volume lever? Is there a way of testing this w/o any special equipment?
thx in advance
dave

[AE_Collector]

Yes, probably best to start a new topic for new problem. I split it for you.

What sort of problem? Ringer doesn't work at all? Do you know about grounded ringing for party lines? This one might have the ringer connected between one side of the line and ground in which case you need to get it across the tip and ring connections through a capacitor of course.

Terry

[axil]

thx terry all other functions are fine except when calling in the ringer wont work. I did notice this condenser(i think) was tucked under the dial and upon further inspection it looks like there is a connector missing if in fact there is supposed to be one there. please see pics I'm sorry im not sure what grounded ringing for party lines means.
thx dave

[unbeldi]

The device that you refer to as a condenser under the dial appears to be a No. 426A cold-cathode electron tube.

The electron tube was used on some party lines and replaces the condenser in the ringing bridge. Its purpose is to keep the impedance of the set very high when not ringing to reduce or prevent inductive noise problems and cross-talk between adjacent lines when such problems exist without the tube.[Revised with more detail to eliminate the chit-chat since.]

An electron tube was used for two purposes:
-For elimination of inductive noise and cross-talk
-For four-party selective and eight-party semi-selective ringing on party lines. For eight parties, code ringing (short/long) was still needed.

A common problem with party lines was that the grounded ringing that was the method of choice for selective ringing in the Bell System caused imbalance of the ring side vs. the tip side of the line with respect to ground, meaning that the two wires of the line had a different impedance to ground. In difficult situations, imbalances cannot be completely eliminated even when connecting the same number of ringers on the tip side and on the ring side of the line. The electron tube eliminated the grounding problem and added the benefit of providing selective ringing for up to four-stations when the ringing current was superimposed on direct current to provide a polarized, pulsating signal.

It is a little bit tricky to make electron tubes work today on standard lines, because their operating principle was based on proper polarity of the line and special superimposed, pulsating ringing current.  Unless you are inclined to experimentation and enjoy originality not only in appearance of your antique phone, but also in operation, then it is best to remove the tube from the circuit.  In the 500-series set, you already have the ringing capacitor contained in the network, that metal can with connecting screws on the top, so the conversion is easy.

Remove the tube and its wires entirely. Connect the ringer in the following manner:

L1 ———black ringer (R) wire——ringer——slate R wire——K-terminal (condenser) A-terminal——slate red R wire——ringer——red R wire———L2

The telephone line connects to L1 and L2.

If you prefer a diagram, here is the 'modern' method of connecting the ringer for 500-series telephones:

[poplar1]

The device that you refer to as a condenser under the dial appears to be a No. 426A cold-cathode electron tube.

The electron tube was used on some party lines and replaces the condenser in the ringing bridge. Its purpose is to keep the impedance of the set very high when not ringing to reduce or prevent inductive noise problems and cross-talk between adjacent lines when such problems exist without the tube.

Of course, the main purpose of the tube was to permit 4-party selective ringing (no other phones would ring other than those of the intended party).

[unbeldi]

Of course, the main purpose of the tube was to permit 4-party selective ringing (no other phones would ring other than those of the intended party).

Well, yes and no.
Four-party selective service was accomplished previously even without electron tubes.  In both cases it requires polarized pulsating ringing current. Without tube is also requires a biased ringer (C-type is that) and (perhaps) a yoke adjustment screw.

[poplar1]

Of course, the main purpose of the tube was to permit 4-party selective ringing (no other phones would ring other than those of the intended party).

Well, yes and no.
Four-party selective service was accomplished previously even without electron tubes.  In both cases it requires polarized pulsating ringing current. Without tube is also requires a biased ringer (C-type is that) and (perhaps) a yoke adjustment screw.

The electron tube replaced the relay that was used in previous sets. 4-party selective ringing was not accomplished simply by adjusting the ringer!

http://www.classicrotaryphones.com/forum/index.php?topic=7584.msg84103#msg84103

[unbeldi]

The electron tube replaced the relay that was used in previous sets. 4-party selective ringing was not accomplished simply by adjusting the ringer!

That is only true for common battery lines.

[AE_Collector]

Axil lives in Penticton, BC. i think the number card on the phone is 604 494 though my first guess was 604 474. All areas outside of the Greater Vancouver area changed from NPA 604 to 250 on October 19, 1996. 250 494 is Summerland BC, close to Penticton BC where as 250 474 is Belmont, close to Victoria BC on Vancouver Island, a long way from Penticton BC.

Until 1993 Summerland was a C1 EAX that was converted to a DMS remote. C1 was Automatic Electric's first Electronic Exchange designed and built by AE Canada at Brockville initially capable of 2400 lines with later versions able to handle 4800 lines. BC was almost exclusively SxS until the C1 became available in the late 60's at which point it was deployed in many smaller communities throughout BC. C1 is said to be an accronym for "Canada's 1'st" (electronic exchange) though it was fairly succesfully sold into the US as well.

I worked for Aramco in Saudi Arabia upgrading switches for a little bit and was more than surprised to find many C1's there in 1985!

I am getting quite off topic. I dont know what the party line ringing set up would have been on the C1. Here in BC for the most part what I saw was frequency ringers and grounded ringing if more than two parties on a line. I dont recall any tubes or relays being used but I didnt work in any rural areas where other problems might have existed such as extra ling lines, carrier etc.

On SxS it was easy to introduce the frequency desired to a shelf of connectors. Presumably electronic switches allowed a frequency to be programmed or at least optioned on the line card? Ultimately as Unbeldi mentioned, maybe tubes were only really required on problem lines, not every party line?

BC Tel used virtually no NE station equipment in that time frame except for the interior area of BC that still somewhat operated like a different phone company even though it was a part of BC Tel. They used a lot more NE equipment there in that era. Axil's 554 has an AE modular conversion plate on the back of it.

Terry

[axil]

thx very much for your help guys. I disconnected the tube all together but i'm having a little trouble understanding the instructions. It seems like it is already wired that way unless i'm missing something. I took a pic hoping you can see what is there and maybe guide me from there.

here's what i have done:

1) telephone line: red to L2 green to L1

2) condensor: red to G ---- black to L1 --- yellow to A

thx dave

[unbeldi]

thx very much for your help guys. I disconnected the tube all together but i'm having a little trouble understanding the instructions. It seems like it is already wired that way unless i'm missing something. I took a pic hoping you can see what is there and maybe guide me from there.
tyhx dave

From your picture it is not evident that you disconnected the tube.  The wires still appear to be there.
I just posted a new topic in the wiring diagram section of the Forum for wiring ringers, as this is one of the most frequently reported problems. Let's keep the discussion here though.  A pictorial diagram in addition to the ringing bridge circuit might help:



Your black ringer wire still appears to be on G, although the spade is not secured tightly. Move it L1 and remove the wires from to the tube.

[unbeldi]

here's what i have done:

1) telephone line: red to L2 green to L1

2) condensor: red to G ---- black to L1 --- yellow to A

thx dave

Well, what you call condensor is the tube, right?  Let's not call it a condenser anymore.   Remove the red, black, and yellow wires leading to it from the network.

[axil]

sorry I used the wrong pic. i have removed the tube and I wired it according to your latest illustration and it is working fine now.
Also the green and red wires were reversed on the line coming in not sure if that makes a difference.
sorry for the confusion re: condenser/tube
thx unbeldi

dave

[unbeldi]

No problem...
Great!

Just one question, was the electron tube secured to the back plate with a screw?

sorry I used the wrong pic. i have removed the tube and I wired it according to your latest illustration and it is working fine now.
Also the green and red wires were reversed on the line coming in not sure if that makes a difference.
sorry for the confusion re: condenser/tube
thx unbeldi

dave

[axil]

No problem...
Great!

Just one question, was the electron tube secured to the back plate with a screw?

no it was kind of pushed under the dial beside where it would have been secured. Not sure why as it was not disconnected.

dave