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NEWBIE WeCo 550-C PBX Info wanted

Started by BigBird0000, June 17, 2017, 11:56:26 AM

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BigBird0000

I just picked up a Western Electric 550-C PBX.
It has the schematic with it, but I am new to phones,
and was wondering if there is any additional info besides the schematic that is available.
It appears to have all the parts.

The Dial doesn't return after rotating  to fingerstop, is there a way to ID the dial so I can find a spring(think its missing) to repair?

Thanks
--alan


IMAGES:

https://ibb.co/album/iBsfrF  --->  ( images copied from external hosting site and attached below )

unbeldi

#1
Welcome !

The board looks nice, but the dial is was added later and is not by Western Electric.

The dial is a Type 24A36 by Automatic Electric Company.  They are easily found.

I am wondering, however, whether it be better to use a Western Electric dial instead, but the board may have been modified for use with the AE dial.   Reviewing the schematics would provide an answer.

Did you remove the wires from the dial, or was it there just for decoration ?

unbeldi

Hmm.  That board actually looks familiar.  Didn't that sell on eBay just recently ?


BigBird0000

The wires were as is.  The dial fits and holds in the metal clip. I am not used to the WE Schematics, so I am going to scan it in to my computer, and whiten background to make it easier.

Yes, it was the one ebay.

Any known installation info on these, or what would be similar? I didn't find on TCI.

Alex G. Bell

#4
Quote from: BigBird0000 on June 17, 2017, 12:52:23 PM
The wires were as is.  The dial fits and holds in the metal clip. I am not used to the WE Schematics, so I am going to scan it in to my computer, and whiten background to make it easier.

Yes, it was the one ebay.

Any known installation info on these, or what would be similar? I didn't find on TCI.
Switchboards except 555s and their derivatives and 608s typically require a dial with one normally open off-normal contact isolated from the pulse contacts since it switches local PBX battery voltage to a relay in the attendant's TEL circuit.  So any AE dial or a WECo 2/4/5/6E or F dial will work interchangeably with no internal connections to the swbd. 

They also will mount interchangeably on a WECo dial mount and might also on an AE dial mount as long as the vertical screws at 3 and 9 o'clock are being used rather than the horizontal screws at 2 and 10 o'clock.  I don't recognize this dial mount from the bottom and am unable to see any screws holding the dial to the mount. 

However in the upper right corner of the photo showing the back of the dial I can see the bottom end of the WECo 25B or 25C connecting block to which a WECo 6000 or 6044 dial mount attaches and makes contact to connect the dial to the keyshelf wiring.  So I suppose it's the back of a 6000-type dial mounting with 20ยบ incline of the dial face. 

It seems to be missing the large ~3" diameter gold colored metal crescent shaped 52-type dial adapter which normally mounts the dial to the dial mount using the 3 vertical screws on the back of the dial and two radial (horizontal) screws to attach the crescent shaped dial adapter to the 6000 type dial mount.

AE dials easily and often fetch up due to dried up lubrication on the governor bearings and may seem to be missing a spring but that's actually very unlikely.  Try putting a tiny drop of oil on the governor bearings being careful not to get any on the inside of the governor cup or fly weights.

What you describe as a schematic is probably not and also not very useful for most purposes.  WECo switchboards usually contain a "T" diagram which is an "air-line" wiring diagram showing the colors of leads from the wiring harness connected to each piece of apparatus (relays, coils, jacks, keys, etc), hence the diagram may help in reconnecting wires broken off terminals but is of zero benefit to understanding circuit operation.  If I were you I would not waste any effort trying to scan it since the same T drawing may already be available as a PDF and surely the actual schematic is, along with the Bell System Practices.

BTW, I'm not sure whether it's a 550C or a 551B.  I thought 550s used separately mounted rather than strip mounted jacks but the orange keys at the left certainly are not characteristic of a 551B so maybe the strip mounted jacks are the difference between a 550B and a 550C.  Something to research in the future.  A complete photo of the face equipment would be helpful for future reference.

Where did you find the "550C" identification?  Look around inside for a 5-digit J-number stamped in orange ink beginning "J5####L where # are numerals and L is one or more letters.  That would be the most definitive ID.

BigBird0000

Alex,

You are correct about the dial, it starts to return, but when the governor should start to open, the return stops. I will oil and check as per your instructions.

You are also correct about the "Schematic", it is a "wiring of circuits".

I found the 550-C on them "schematic" attached to a metal cover. I haven't seen the "J#" yet, but am still looking.

I have uploaded pics of the "schematic" and other pics of the PBX to https://bigbird0000.imgbb.com/
until I move them to the other album.

I will post any updates

Alex G. Bell

Quote from: BigBird0000 on June 17, 2017, 06:13:39 PM
Alex,

You are correct about the dial, it starts to return, but when the governor should start to open, the return stops. I will oil and check as per your instructions.

You are also correct about the "Schematic", it is a "wiring of circuits".

I found the 550-C on them "schematic" attached to a metal cover. I haven't seen the "J#" yet, but am still looking.

I have uploaded pics of the "schematic" and other pics of the PBX to https://bigbird0000.imgbb.com/
until I move them to the other album.

I will post any updates
Good! 

Correction to my previous statement: ...with no internal connections wiring changes...

BigBird0000

Mr. Bell,

As you suggested, the drop of oil on the bearings helped. The dial is working great after just a minute or two.


Alex G. Bell

Quote from: BigBird0000 on June 17, 2017, 07:59:48 PM
Mr. Bell,

As you suggested, the drop of oil on the bearings helped. The dial is working great after just a minute or two.
Great!  Thanks for getting back to us.

AE dials are especially vulnerable to this problem.  In general the higher speed a shaft spins the more dry lubrication results in unacceptable drag. 

The worm gear drive on AE dials makes this especially so because it gears up the governor speed and also has drag of its own because there is a lot of surface contact area and sliding of the surfaces against each other compared to the way ordinary toothed gears mesh, hence friction between the surfaces.  So a tiny amount of oil on the spiral of the worm gear will also probably help.

BigBird0000

I'm going to clean off any goo *the techie word", and then put down the thinnest layer of oil.
I will also CRC clean the contacts, and burnish if necessary, then figure out wiring.
I need to find somehting to open op the shelf  to spray clean the contacts for the switches.
then the jacks and plugs. before I even start the back. I also need to get the drops of paint off,
and refinish the cabinet

Then try and hook up some of those magneto phones.

Why is it you loose personal time when you retire?

--alan

Still looking for install and/or operating manual for this pbx.

I plan on sending all the files I find to TCI library!




Alex G. Bell

Quote from: BigBird0000 on June 18, 2017, 12:55:47 AM
I'm going to clean off any goo *the techie word", and then put down the thinnest layer of oil.
I will also CRC clean the contacts, and burnish if necessary, then figure out wiring.
Might well not be necessary to clean contacts.  I'd wait until it's powered up to see what works and does not.  I've powered up equipment that sat around for decades in adverse storage conditions and it worked perfectly with no contact cleaning.

Do you have appropriate power for it?

You need a lamp cap and lamp puller to get the lamps out without damage.  Even with these sometimes the contacts come off and they become unusable.  Often swbds which were in service late have completely inappropriate lamps because the repairman used whatever he could get as support and supplies waned.  So you should check lamps. 

Sometimes it's best to wait until it's powered and judge by their brightness to decide whether they are correct or not to avoid damage to lamps by removal just for inspection.

Burnish only with a bonafide relay contact burnishing tool.  Anything else can remove precious metal and destroy contacts.
Quote from: BigBird0000 on June 18, 2017, 12:55:47 AM
I need to find something to open op the shelf  to spray clean the contacts for the switches.
then the jacks and plugs. before I even start the back. I also need to get the drops of paint off,
and refinish the cabinet
Do you mean the key for the key shelf?  It's standard for all 550s, 551s & 552s, possible though expensive to copy because the blanks are in low production and costly.  I have an original and can look into having it reproduced.

Again I would be cautious and not plunge head long into contact cleaning.

You might want to read some of the topics related to restoring finish on wood phones.  Original finish restored may be better and more authentic than a new finish.
Quote from: BigBird0000 on June 18, 2017, 12:55:47 AM
Then try and hook up some of those magneto phones.

Why is it you loose personal time when you retire?

--alan
This is a common battery switchboard.  It is not compatible with magneto phones as-is.  There are ways to adapt depending on what you want to achieve.  We can discuss that later.

Sorry, I don't answer existential questions on this list.  It would be off-topic.  ;D
Quote from: BigBird0000 on June 18, 2017, 12:55:47 AM
Still looking for install and/or operating manual for this pbx.

I plan on sending all the files I find to TCI library!
OK, good.

You can identify the relevant installation and maintenance Bell System Practices from BSP 000-000-002, BSP Master Index or division indexes 534-000-000 and 536-000-000 in the TCI library.  Look in divisions 534 and 536 in the Master Index.

The operating booklet for the 551 type is probably completely appropriate since the 551 was a redesign to use later apparatus and change some ergonomic aspects but is not functionally different.  PBX operating booklets are around.  Not sure whether I have the 551 but I might, not scanned though.

BigBird0000

Alex,

Thank you so much for the detailed answers and comments.

I will look at the BSPs you suggested.

It would be great if you can find out about a key being copied. If not, would it be possible to take a couple of close up shots
next to a ruler (metric or standard) so I can measure it (also from the "hole side" of the key (opposite side of the bow, or handle of key)
with dimensions, I would be able to make a key.

I am pretty good at relay (and leaf switch contacts) - I have restored many Jukeboxes and Pinball machines from the 20's to the 60's, and have burnishing tool and usually use a business card with contact cleaner first.

I do not think I have a power supply, thats why I am looking for schematic/install/maintenance.

Happy fathers day to you - the man that fathered my latest hobby!


--alan

Alex G. Bell

#12
Quote from: BigBird0000 on June 18, 2017, 12:07:13 PM
Alex,

Thank you so much for the detailed answers and comments.

I will look at the BSPs you suggested.

It would be great if you can find out about a key being copied. If not, would it be possible to take a couple of close up shots
next to a ruler (metric or standard) so I can measure it (also from the "hole side" of the key (opposite side of the bow, or handle of key)
with dimensions, I would be able to make a key.

I am pretty good at relay (and leaf switch contacts) - I have restored many Jukeboxes and Pinball machines from the 20's to the 60's, and have burnishing tool and usually use a business card with contact cleaner first.

I do not think I have a power supply, thats why I am looking for schematic/install/maintenance.

Happy fathers day to you - the man that fathered my latest hobby!


--alan
You're welcome Alan.

I think I may have photographed the key and dimensioned it by measuring with a vernier caliper.  I'll look around for that and also see if there is anyone around who can copy it.

The pinball machines and juke boxes I've seen in my youth (not recently) had industrial type relays with much larger contact buttons.  Telephone relays are somewhat more delicate.  Some contacts intended for dry circuits have gold flashing which will be removed by anything abrasive.  But your experience with electro-mechanical equipment is certainly a useful and relevant skill to bring to the table.

Business cards may deposit wood fiber in the pits of pitted contacts.  There is special high rag content paper strips which are used in telephone equipment maintenance.

Look for other recent threads on CRPF about lamp cap and lamp removal tools.  I'm pretty sure you need 24VDC or thereabouts and a source of 65-90VAC 20Hz ringing current.  Will see if I can locate my SDs to confirm that.  However most manual PBXs operate over a range of voltages and require the lamps to be matched to the voltage used.  IIRC, 550s and 551s operated over a range of 20-36V.

An excellent choice if you can find one at a reasonable price is the Tellabs 8050.  It's a switched mode unit, therefore is quite compact and standby power is low if you choose to leave it powered up.  It has switches to set the outputs to 24 or 48VDC and the ringing source to 20 or 30 Hz.  Switchboards always use 20Hz.  It also has a 10VAC 60Hz output for key telephone systems, so if set to 24V could power one of those too.

Common key telephone system supplies such as the 101G or 20- or 30 types use saturated core devices to produce the ringing current which have much higher standby power consumption, heat production and are much larger.  The 101G versions which provide ringing provide 20Hz while the 20- and 30-types produce 30Hz which is not appropriate and produces a somewhat "frenetic" sound at the ringers since they're operating at 150% of the correct rate. 

20Hz will sound better to you once you've heard them both and recognize the difference.  When you get to that stage, the longer clapper rods on these older type ringers may make your magneto telephone ringers not respond well to 30Hz, never tried it. 

Thanks for the holiday greetings.  You too.

BigBird0000

Alex,

I gave a tellabs 8050. Went in the garage this am to find it, before the temp goes up
to 122 today.

I am going through everything you mentioned, and I downloaded.

When I do relays/leaf switches, I am always careful. A lot of the jukebox stuff was gold plated, so I am very aware of
the dangers, but thanks anyway.

I will let you know when I have any updates -- hopefully soon.

--alan

Alex G. Bell

Quote from: BigBird0000 on June 19, 2017, 11:09:08 AM
Alex,

I gave a tellabs 8050. Went in the garage this am to find it, before the temp goes up
to 122 today.

I am going through everything you mentioned, and I downloaded.

When I do relays/leaf switches, I am always careful. A lot of the jukebox stuff was gold plated, so I am very aware of
the dangers, but thanks anyway.

I will let you know when I have any updates -- hopefully soon.

--alan
OK, good.  122?  Where?