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My first multi-line phone.

Started by Greg G., April 11, 2011, 11:03:18 PM

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Greg G.

A 302 with buttons.  I just won this on ebay.  I gave instructions about packing, keeping my fingers crossed that it won't arrive smashed.

Update:  Not a 302, a 440.  Basically a multi-line version of the 302.
The idea that a four-year degree is the only path to worthwhile knowledge is insane.
- Mike Row
e

ESalter

I saw that one too!  I was thinking about bidding but decided not to.  I have one of the 5 line and hold models(464GA, i believe).  It's one of the older models with bakelite buttons.  It's a really nice phone.  I'm sure you'll really like yours as well.  Have a plan for hooking it up?  Mine is hooked to a PBX.  I believe these will work on a 1a2 key system as well, but I could be wrong.

Adam

Very cool phone!

But, I'm wondering, why is there a big vermilion A in the number card area?
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

GG



The vermillion "A" is on the flexible plastic disc that protects the dial number card.  I've seen examples with other letters, and I believe this had something to do with party line ringing.  If that's true, it wouldn't be original on a multi-line phone; I can't imagine multi-line phones being used on party lines.  However, it's easy enough to replace with a plain clear one (keep it in your spares box).

I have a 5-line version of that phone.  If you wanted to use it on a PBX you could wire consecutive extension numbers to the line keys, and use hookflash + PBX hold feature code to put lines on hold.  Though, ideally you'd find a 1A1 or 1A2 key service unit for it.  What would be max cool is if someone manufactured a little circuit that provided 1A2 emulation for 1 - 5 lines, using modern AC power transformers that are more efficient for one phone than using an entire 1A2 KSU. 

Dennis Markham

This Mahogany 510 E/F has a similar card with the letter "B" on the acetate disc.  This is a two line set and according to Paul F's site they were used on early PBX systems.  I refurbished this set for another collector a year or so ago. 

I'd leave the "A" card on there.  It may be original to the phone. 

paul-f

Quote from: masstel on April 11, 2011, 11:43:21 PM
I'm wondering, why is there a big vermilion A in the number card area?

That's a Form E-2959-A, covered in BSP C37.321, I5, section 2.27.  Apparently there were "forms" from -A to -Z (except -I) with the corresponding letter on the disk.

"At multi-station key telephone set installations, as in the 1A and 1A1 Key Telephone Systems or in 750A or 755A P.B.X. systems, etc., substitute these windows in the station number card holders for the regular windows ... to designate stations A, B, C, etc., in accordance with the work sheet data furnished with the service order.  Also refer to these letter designations when reporting station visits for either installation or maintenance reasons."

Perhaps someone can check the KTS and PBX BSPs to see if there's more info there.

There must be a reason for the coding.  Perhaps it identifies sets wired in a department or work group, or to identify sets with special features, such as access to an external line or tie line.
Visit: paul-f.com         WE  500  Design_Line

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GG



I'll defer to Dennis & Paul here.  Interesting mystery. 

It's unlikely to refer to intercom buzzer codes (multiple pushbutton units attached to the sides of phones) because then you wouldn't see it on a 2-line set or other phones found w/o those outboard buttons. 

It's unlikely to refer to PBX extension hunting because per Paul's item, 1A and 1A1 KTSs don't have "extensions" in the sense that PBXs do.   

In a KTS w/o 90-volt ringing supply, such as some variants on 1A1, it could refer to the CO line to which a ringer is connected: thus, the phone that rings on line 1 = A, the phone that rings on line 2 = B, etc.  Though, in a PBX, all lines would ring at the operator's console unless put on night service, and many PBXs were installed without KTSs behind them.

Whatever it is, also necessarily provides some useful information to the station user.  If it was intended only to inform telco techs of something, it would be on a label stuck on the bottom of the phone such as was done with KTS phones to note items such as the location of the IDF to which the phone was connected.   

Looking forward to someone finding the answer to this. 


Owain

Quote from: paul-f on April 12, 2011, 11:06:50 AM


That's a Form E-2959-A, covered in BSP C37.321, I5, section 2.27.  Apparently there were "forms" from -A to -Z (except -I) with the corresponding letter on the disk.

"At multi-station key telephone set installations, as in the 1A and 1A1 Key Telephone Systems or in 750A or 755A P.B.X. systems, etc., substitute these windows in the station number card holders for the regular windows ... to designate stations A, B, C, etc., in accordance with the work sheet data furnished with the service order.  Also refer to these letter designations when reporting station visits for either installation or maintenance reasons."

Perhaps someone can check the KTS and PBX BSPs to see if there's more info there.

There must be a reason for the coding.  ....

It would be necessary to identify each station unambiguously, as those systems didn't have internal extension / intercom numbers. Rather cumbersome to have to write "Elsie's phone" or "the one in the cupboard with the leaky ceiling" on work dockets etc.

Adam

I agree with GG who said:

QuoteWhatever it is, also necessarily provides some useful information to the station user.  If it was intended only to inform telco techs of something, it would be on a label stuck on the bottom of the phone

Unambiguous identification would fall into that second category.  It's not relevant to the phone user, so why stick the info in their faces?
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

Adam

I have a guess:  Perhaps it identifies which line the set rings on?

On a 1A1/1A2 key system, the appropriate button lamp flashes when its line is ringing.

However, the earlier 1A key system doesn't have ringing lamps (or any lamps at all).  So, maybe the A, B, C, etc. on the number card retainer corresponds to what line the particular set is wired to ring on.

The fact that Dennis' Mahogany 510 E/F has a "B" on it fits with this, since it's only a two line phone, it could only have an A or a B.

Like I said, just a guess.
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

paul-f

Dave,

Interesting theory, but it doesn't seem to fit with disks lettered from A to Z.

I asked on the club lists and got this response so far.

"During the period of approx. 1950 through 1970, key equipment installers were issued a form known colloquially as a "K-plan."  It was a form that had boxes representing the keys on 6-button sets (10-button and bigger had not been invented yet. Call Directors® used different, but similar, forms.)

The term K-plan also was used to refer to the actual key equipment on the premises.

The form was transmitted via company mail from the sales rep in the business office -- or in the case of very large installations, by the "Communication Consultant" who had the account -- to the local installation field office. The installer would use the form as a guide for his work at the premises, and would leave a copy folded up inside the KSU cabinet for future reference.

At the top was the usual name address, main listed number, etc, of the subsciber.

Going down the left side was the station telephone model #, the station letter, from A to Z, and across the paper, horizontal rows of boxes, about a half-inch square, into which were written the designations (line numbers, restrictions, dial selective intercom codes, signal keys, etc.) that were to be assigned to the buttons on each set. The letters for each station were assigned arbitrarily.

There was also a place on the form for ancillary equipment, such as external bells, busy lamps, etc.

The little letters were essentially ignored after the first inspection of the installation. Repair bureau personnel (at least where I worked) were not trained to ask the calling subscriber for the station letter. Therefore the station letter info was not disseminated further down the food chain when a repairman was dispatched."


Several members may have copies of the form, so we may see details.

Apparently the letter was simply a convenience to help repair folks find the details of how the set was originally wired on the work sheet - hopefully saving time gathering background info before the repair could start.
Visit: paul-f.com         WE  500  Design_Line

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Adam

#11
Thanks for that info, Paul. That is is probably the correct answer to the meaning of the big vermilion letters on the number cards.

However, as noted previously, it doesn't make sense for this K plan number to be constantly in the customer's face on the phone's number card, as the customer was never asked for the info in relation to service, moves or changes requests.  It was only something the repairman would want to know, and therefore a more appropriate location for this info would have been a sticker on the underside of the set.

Definitely a very neat and rare artifact of the Bell System at work, to be preserved whenever discovered!

BTW, while on the subject of "K plan", in the New York Telephone Company world, a 6-button set was called a "KV".  I think this is obviously related.  I always assumed, but have no evidence, that this stood for "Key 5" (key set with 5 line appearances).

Also, a single line set was called a "CV".  I have no idea why.
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

paul-f

I agree, Dave, and have asked a follow up question.  We may learn more.

There was also discussion of windows with smaller letters positioned in the lower half of the window.  I found a photo of a smaller letter in the upper half, so there may be several variations.  Has anyone seen others?
Visit: paul-f.com         WE  500  Design_Line

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GG



Yee-haww!, I think we have a winner!  Count on Paul F to find the impossible-to-find information.  Now the rest of it starts to fall into place. 

Why the letters were in the subscribers' face after that: 

Many large KTS installations of that era came without any kind of intercom selector or other means to identify an individual phone unambiguously from its connections to the system (unlike a PBX where every phone necessarily has an extension number).  In these cases, subscribers often had intercom systems that were provided by independent companies (not the telco).  So all the KTS phones would have been wired in parallel in an undifferentiated manner, and the only unique identifier was an intercom station number that was not part of the telco's information and not to be counted on.  That, plus the red letter. 

If, per Paul's friend, the business office & repairs reps were not asking for the red letters, it would have been because the subscriber already identified the phone unambiguously, e.g. "the phone in Mr. Smith's office sounds scratchy." 

But if a subscriber had no clear way of identifying which phone they wanted worked on ("it's one of the ones in the vacant office where the drafting department was, before we moved them to the East corner of the building..." uh-oh!), then the telco rep could ask for that red letter as a means of clearly identifying the phone in question. 

Also if a tech had to de-install a phone (e.g. "Bob's no longer with us and we're going to remove his desk to make more room for Carla") but leave it on site for future reassignment (large installations such as city government offices might have arrangements to keep those on site), then the red letter would let them know something about that phone later (e.g. "why was key #5 on that set wired that way?"), and/or identify it clearly when it was re-installed at another desk later. 

This is starting to sound like "convergent information." 


Greg G.

Y'all get an "A" for solving the mystery!
The idea that a four-year degree is the only path to worthwhile knowledge is insane.
- Mike Row
e