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Brazilian Ericsson switchboard

Started by escuta, July 28, 2017, 10:47:50 AM

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escuta

Hi Forum,

I recently acquired an old hotel switchboard made by Brazilian Ericsson ("Ericsson do Brasil"). I emailed a message about it to the Singing Wires mailing list. People there were very helpful with information, but no one had any specific knowledge about the particular machine, so I'm posting here too - sorry to anyone who is seeing this information twice.

I'm hoping to restore this machine and if anyone has any specific information about its history, parts or even circuit diagrams, please let me know. I have seen another floor-standing model for sale here in Brazil that had an integral wooden base. I also saw a photo of an near identical unit, albeit with configured differently, from a hotel in Mexico.

From a suggestion on the Singing Wires list, I had a look at one of the lamps which had a voltage rating marked of 24V. Someone there thought that the lamp may be of American origin rather than European.  Perhaps it was assembled in Brazil using components from various sources. Please see the photos attached.

While I'll be doing some of the simpler restoring tasks myself (rewiring the patch cords and hand-piece, cleaning, etc), I'm currently looking for a technician to assist with the electronic side of things.

Please reply to this thread if you have information on the machine or any suggestions.

All the best!

Alex G. Bell

#1
Quote from: escuta on July 28, 2017, 10:47:50 AM
From a suggestion on the Singing Wires list, I had a look at one of the lamps which had a voltage rating marked of 24V. Someone there thought that the lamp may be of American origin rather than European. 
The lamp in the photo is marked "Philips".  I'm pretty sure Philips did not mfr lamps in the US.  GE, Chicago Miniature and Sylvania as well as AT&T's Western Electric were the US mfrs.   Philips did own Dialco (originally "dial light company"),  a mfr of pilot light socket assemblies used primarily in radio and other electronic equipment but I'm quite sure no lamps were mfd under that name either.  I don't know the history of Philips' acquisition of Dialco.

You might find an article in the "Ericsson Review" describing this switchboard.  I believe there is an archive on line on L. M. Ericsson of Sweden's site. 

The information stamped next to "tipo" and "no." on the ID plate in your photo do not seem to be legible.  If you can read them when directly viewed I suggest posting this information here.  It may facilitate finding documents or an Ericsson Review article.  Searching purely based on description would be too time consuming.

unbeldi

#2
The inscription on the lamp clearly identifies the manufacturer as Philips NV.  Philips was an early and still is a major lighting equipment maker in Amsterdam. So, it seems logical that this switchboard was equipped with European parts.   I think, that an American switchboard would most likely use General Electric, Sylvania, or Western Electric lamps.  Some switchboard makers, such as Kellogg S. & S. Co even made their own lamps.

Selection of the right kind of lamp for your board probably depends on the design of the supervisory circuits.  If the lamp current is switched with a line relay, its resistance is perhaps less critical, as when the lamp is directly inline with the station.

Since you have a lamp, have you measured its cold resistance ?

Are there any type numbers on that type tag ?


BTW, a switchboard is not a machine.  I find that characterization rather distracting.  It's all manual work to make this equipment work.
A step-by-step switching system could be called a machine.

unbeldi

By the type of wood work in this unit, I think that it may have been made middle-1930s to ~1950 perhaps.

Alex G. Bell

#4
Quote from: unbeldi on July 28, 2017, 12:32:15 PM
The inscription on the lamp clearly identifies the manufacturer as Philips NV. 
...
Selection of the right kind of lamp for your board probably depends on the design of the supervisory circuits.  If the lamp current is switched with a line relay, its resistance is perhaps less critical, as when the lamp is directly inline with the station.
...
BTW, a switchboard is not a machine.  I find that characterization rather distracting.  It's all manual work to make this equipment work.
A step-by-step switching system could be called a machine.
Ah!  Could not make out the "NV" although I'm familiar with their full name.

From the rear photo, it does not seem that there are enough relays in the unit for there to be line relays, probably just cord circuit relays.  Even much larger PBXs such as WE 551 and 555 did not use line relays except when added individually for specific off-premises extensions.

Panel and Crossbar (XB) exchanges were also referred to as "machines", no stretch at all for Panel and not too much of a stretch for XB.  In fact the Bell System originally used the term "machine switching" rather than "automatic" or "dial" to refer to what generally became known as dial service.  Funny but with the evolution to ESS with stored program control and even digital ESS with no relays to speak of, the term "machine" continued to be used.  Old habits die hard.

unbeldi

Quote from: Alex G. Bell on July 28, 2017, 01:05:09 PM
Ah!  Could not make out the "NV" although I'm familiar with their full name.
Oh, I just used the NV without reference to the actual inscription on the lamp.  I am not sure what it is that follow the mark "PHILIPS" on that lamp.


Quote
From the rear photo, it does not seem that there are enough relays in the unit for there to be line relays, probably just cord circuit relays.  Even much larger PBXs such as WE 551 and 555 did not use line relays except when added individually for specific off-premises extensions.
I suspect so also, the board is rather small, and it is not likely that it was made for stations to be so far away that it would require line relays.
From the small Kellogg cordless boards I know that they equipped only the 20-station boards with line relays, not the smaller ones.

Quote
Panel and Crossbar (XB) exchanges were also referred to as "machines", no stretch at all for Panel and not too much of a stretch for XB.  In fact the Bell System originally used the term "machine switching" rather than "automatic" or "dial" to refer to what generally became known as dial service.  Funny but with the evolution to ESS with stored program control and even digital ESS with no relays to speak of, the term "machine" continued to be used.  Old habits die hard.
Agreed.   One might however say, that this switchboard contains simple machines, which are devices, like the levers of keys, that transform energy in a very basic manner.

Originally, machines transformed energy into mechanical energy, but it has been extended to electronic devices, such as computers even.


Alex G. Bell

Quote from: unbeldi on July 28, 2017, 02:02:30 PM
From the small Kellogg cordless boards I know that they equipped only the 20-station boards with line relays, not the smaller ones.
Probably also a function of the intended operating voltage range.  They may have included line relays to permit operation over a wider range including lower voltages.
Quote
Agreed.   One might however say, that this switchboard contains simple machines, which are devices, like the levers of keys, that transform energy in a very basic manner.

Originally, machines transformed energy into mechanical energy, but it has been extended to electronic devices, such as computers even.
That always seemed to me like a stretch to the breaking point.  As I see it, just because the disk drives are machines that does not make the whole thing a machine.  It's principle function is computation which does not employ mechanical devices, which just provide storage.  I'd make the same case for a manual swbd.

unbeldi

Quote from: Alex G. Bell on July 28, 2017, 02:13:00 PM
That always seemed to me like a stretch to the breaking point.  As I see it, just because the disk drives are machines that does not make the whole thing a machine.  It's principle function is computation which does not employ mechanical devices, which just provide storage.  I'd make the same case for a manual swbd.
I have lingering objection to that inclusion myself, and I don't promote the term for computers myself, but have come to accept it.

Alex G. Bell

Quote from: unbeldi on July 28, 2017, 02:19:26 PM
I have lingering objection to that inclusion myself, and I don't promote the term for computers myself, but have come to accept it.
Yes, a few years after publication of "The Soul of a New Machine" I stopped bristling at mention of the title.   ;D  It just was not worth the emotional energy!

TelePlay

Quote from: unbeldi on July 28, 2017, 02:02:30 PM
Oh, I just used the NV without reference to the actual inscription on the lamp.  I am not sure what it is that follow the mark "PHILIPS" on that lamp.

Seems "IMP." is an abbreviation but what comes after that, the font does not match.

Alex G. Bell

Quote from: TelePlay on July 28, 2017, 02:38:25 PM
Seems "IMP." is an abbreviation but what comes after that, the font does not match.
Yes, "IMP" might be a reference to a version with reduced size from the standard.  Time for the OP to read the lamp and the ID plate and tell us what they say.  No point spending more time guessing and speculating.

escuta

Thanks Alex G. Bell and unbeldi. That Ericsson Brazil plaque unfortunately has the type and number fields left blank. On the lamp, from memory (I put the lamp back in the switchboard), the figures following "IMP." (imperial?) look like "AA" but with the crossbar of the first "A" missing. Tomorrow I'll have a chance to remove another bulb. If I can I'll attempt to retrieve a different lamp to see if the stamp is any clearer. Thanks for the tip on the Ericsson review. I did find a list of them on the following page, however the links appear not to open the PDFs on the Ericsson site:

http://runeberg.org/ereview/

Are you aware of an current online source of the reviews?

I have some more photos, will post some in this post and some more in another.

escuta

some more...

unbeldi

#13
I believe this board should actually be wall-mounted, correct?
How else would the cords be able to retract properly ?

I think the design with rounded corners may have been a post-WWII design in Sweden.
In the US, I think it was only Kellogg that did that, but they started building in the style in the 1930s.  Stromberg-Carlson boards were still more "sharp-edged", and AE and WECo had even more-old-fashioned designs.

I think this timing is also supported by the style of screws, etc.


Alex G. Bell

Quote from: escuta on July 28, 2017, 03:38:15 PM
Thanks Alex G. Bell and unbeldi. That Ericsson Brazil plaque unfortunately has the type and number fields left blank.
Too bad.  However LME was pretty consistent about using uniform letter prefixes (defined by themselves) before their model #s, such as "ARD" for crossbar exchanges.  There's probably some (currently unknown) prefix for cord swbds and once we determine what it is, knowing it may facilitate finding a specific article.
Quote
On the lamp, from memory (I put the lamp back in the switchboard), the figures following "IMP." (imperial?) look like "AA" but with the crossbar of the first "A" missing.
In other words an upside down "V".  I don't know what that means but perhaps a search for Philips switchboard lamp catalogs will turn something up.
Quote
Tomorrow I'll have a chance to remove another bulb. If I can I'll attempt to retrieve a different lamp to see if the stamp is any clearer. Thanks for the tip on the Ericsson review. I did find a list of them on the following page, however the links appear not to open the PDFs on the Ericsson site:

http://runeberg.org/ereview/

Are you aware of an current online source of the reviews?

I have some more photos, will post some in this post and some more in another.
You're welcome.  I've never encountered the runeberg.org site before.  At one time the magazine itself was on the LME site but I have not looked at it in a few years and have migrated PCs without migrating bookmarks so I may or may not have the URL I used in the past. 

The articles might still be on the LME site but with a minor reorganization of the site, the exact path could change rendering them all invalid.  I suggest trying to explore the LME site by navigating back towards the home page from one of the links contained in the Runenberg.org page.  That might not lead anywhere but it also might lead you to the archive.

I may have an LME E-R article index from the time when I accessed the LME E-R archive but cannot spend time looking for it at this moment.  I think I also have a cache of British Ericsson articles.  It's certainly possible they sold this swbd in multiple countries and that there's an article about it among them but again I cannot spend the time right now.