Author Topic: Western Electric 2500 diagram & Assembly help needed  (Read 384 times)

Western Electric 2500 diagram & Assembly help needed
« on: August 06, 2017, 08:59:50 PM »
Does anyone have the schematics for the dialpad? Between the two layers of it; I can't figure out how those plastic pieces are supposed to go back. Mine was filthy thanks to a relative, and I didn't quite memorise exactly how it was before taking it apart (distracted by the filth)

Alex G. Bell

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #1 on: August 06, 2017, 09:16:29 PM »
Does anyone have the schematics for the dialpad? Between the two layers of it; I can't figure out how those plastic pieces are supposed to go back. Mine was filthy thanks to a relative, and I didn't quite memorise exactly how it was before taking it apart (distracted by the filth)
I take it you disassembled the keypad. 

No schematic includes a mechanical assembly drawing for the keypad.  It's not supposed to be disassembled in the field. 

Also, there is an implicit assumption in your question that all keypads are the same since you did not specify the code # of the one you have.  That's not necessarily so.

However ITT published a shop procedure for their 32 & 36 type TT dials.  They are close mechanically to the WE 25 and 35 type keypads, the most common ones.  This procedure contains an exploded view and details about constructing an assembly jig.  This might help you.

Look for "ITT_55-032-117 - DTMF Dials 32 & 36" on the TCI library site: http://telephonecollectors.info/

Re: Western Electric 2500 diagram & Assembly help needed
« Reply #2 on: August 06, 2017, 11:40:34 PM »
I take it you disassembled the keypad. 

No schematic includes a mechanical assembly drawing for the keypad.  It's not supposed to be disassembled in the field. 

Also, there is an implicit assumption in your question that all keypads are the same since you did not specify the code # of the one you have.  That's not necessarily so.

However ITT published a shop procedure for their 32 & 36 type TT dials.  They are close mechanically to the WE 25 and 35 type keypads, the most common ones.  This procedure contains an exploded view and details about constructing an assembly jig.  This might help you.

Look for "ITT_55-032-117 - DTMF Dials 32 & 36" on the TCI library site: http://telephonecollectors.info/

THANK YOU!! The dialpad is back together!!! I found a scema of a similar enough dialpad that told me what I need to know on the site you gave me.

U figured it wasn't meant to be dissasembled by the difficulty of accessing the screws, but there was definitely filth in there.

The problem persists; the problem I took it apart for--No tone in dial, doesn't dial.   The only ID I can find on it is what I'd guess is a serial no., 750490 004 6 77. Unless there's a tell in the sequence or length, I doubt that helps.

This is my very first time repairing a phone. My thing has always been radio and all manner of tape players.

Re: Western Electric 2500 diagram & Assembly help needed
« Reply #3 on: August 06, 2017, 11:52:38 PM »
...also a magnetic droning ring over the dial tone.

Re: Western Electric 2500 diagram & Assembly help needed
« Reply #4 on: August 07, 2017, 12:34:15 AM »
Here is the  phone, and I am not getting a clear answer online whether it's the 2500D or the 2500DM.

Alex G. Bell

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #5 on: August 07, 2017, 01:38:02 AM »
THANK YOU!! The dialpad is back together!!! I found a scema of a similar enough dialpad that told me what I need to know on the site you gave me.

U figured it wasn't meant to be dissasembled by the difficulty of accessing the screws, but there was definitely filth in there.

The problem persists; the problem I took it apart for--No tone in dial, doesn't dial.   The only ID I can find on it is what I'd guess is a serial no., 750490 004 6 77. Unless there's a tell in the sequence or length, I doubt that helps.

This is my very first time repairing a phone. My thing has always been radio and all manner of tape players.
These parts (no telephone parts except payphone coin box locks) are serialized.  They are commodities.  The numbers you cited make no sense to me but your photo looks like that of an ITT phone judging from the color matched rather than complementary faceplace.

I don't know what "no tone in dial" means.  If you're a radio guy, measure the frequencies the dial generates when connected to a line and dialing.  Press 2 buttons in a row and 2 in a column to generate a single tone which can be measured with a frequency counter.  The ITT practice I cited discusses how to test dials.

Alex G. Bell

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #6 on: August 07, 2017, 01:41:20 AM »
Here is the  phone, and I am not getting a clear answer online whether it's the 2500D or the 2500DM.
D has cords connected with spade tips under screw terminals.  DM has clear plastic miniature modular plugs on the cord ends.  It's irrelevant to your problem.

Alex G. Bell

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #7 on: August 07, 2017, 01:41:55 AM »
...also a magnetic droning ring over the dial tone.
Not a description I understand.

Online HarrySmith

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #8 on: August 07, 2017, 07:58:13 AM »
It may be a polarity issue. Try reversing the red & green line connections.
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Alex G. Bell

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #9 on: August 07, 2017, 08:13:14 AM »
I don't believe it is a Western Electric 2500 at all.  What are the number markings on the bottom surface of the phone base?

Re: Western Electric 2500 diagram & Assembly help needed
« Reply #10 on: August 10, 2017, 01:26:44 AM »
I don't believe it is a Western Electric 2500 at all.  What are the number markings on the bottom surface of the phone base?

Yeah,it is an ITT, actually. The markings on the bottom of the base are the ones you said make no sense to you. This is actually my third language, by the way.

So, the droning magnetic ring went away, but there is no whatever you call the sound when you press the keys on most keys. A few there's a faint chirp, but it doesn't actually dial. Most, it just goes quiet when you press the buttons. (And this was why I took apart the keypad, not a result of it. I thought the contacts might have been dirty) I tried letting it 'hear' another phone dialing and make the call, but that didn't work, either. When I recieve a call, the other person is almost inaudible and they can't hear me.

Alex G. Bell

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Re: Western Electric 2500 diagram & Assembly help needed
« Reply #11 on: August 10, 2017, 01:37:35 AM »
Yeah,it is an ITT, actually. The markings on the bottom of the base are the ones you said make no sense to you. This is actually my third language, by the way.

So, the droning magnetic ring went away, but there is no whatever you call the sound when you press the keys on most keys. A few there's a faint chirp, but it doesn't actually dial. Most, it just goes quiet when you press the buttons. (And this was why I took apart the keypad, not a result of it. I thought the contacts might have been dirty) I tried letting it 'hear' another phone dialing and make the call, but that didn't work, either. When I recieve a call, the other person is almost inaudible and they can't hear me.

TouchTone dials originally were sensitive to line polarity: which phone cord lead you connected to which line wire or terminal and hence in which direction the DC current passes through the phone.  When the polarity is reversed the transistor which produces and sustains the tones is not able to function so you just hear a chirp which decays immediately. 

Later TT phones were not polarity sensitive but we don't know what type of dial you have. The dial is usually marked with a code on the front of the frame.  "32" is a typical code without the letter suffixes.  The document given in Reply #1 gives more details.  Dials that have an "OPG" suffix have a "polarity guard and polarity does not matter.

The most common cause of the problem you described is reversed polarity.  If it does this after flipping the line cord connections relative to the wall terminals the dial transistor is probably failed.

BTW, even an ITT 2500 set includes "2500" in the part # ID marking.
« Last Edit: August 10, 2017, 08:38:20 AM by TelePlay »

Re: Western Electric 2500 diagram & Assembly help needed
« Reply #12 on: November 14, 2017, 08:19:31 PM »
Lost my internet for a while. It say 32 G on one line, the next line says 8-77 and theres a big "6" on the right that takes up two lines. It also says 8 77 in that long serial string stamped on the bottom. At this point, I'm guessing it was a manufacture date.

Using the internet, I'm guessing it's a 2500MBA; I can't find any other identifying marks. Of course, I can only find Cortelco schematics for "similar" phones.

I tried reversing polarity--I think my colourblindness got me. Anyway, once I put it back and just reversed what I was supposed to, the dial tone chirp just got shorter.