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Mysterious WE 500 Prototype on Ebay

Started by Kenton K, September 30, 2014, 11:50:10 PM

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paul-f

This was from one of a series of field trials (including Morris) of electronic ringers during the late 1950s and early 1960s, starting with Crystal Lake, IL in 1956.

Search the TCI Library for "BLR tone ringer"

As I recall, Ericsson had already pioneered tone ringers by that time.

Similar sets have been shown at several past telephone shows.
Visit: paul-f.com         WE  500  Design_Line

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paul-f

For more technical details, see these Bell System Technical Journal articles:

"Tone Ringing and Pushbutton Calling," March 1958, page 340.
  http://www3.alcatel-lucent.com/bstj/vol37-1958/articles/bstj37-2-339.pdf

"An Experimental Switching System Using New Electronic Techniques." (Joel, A.E., Jr.) September 1958, BSTJ v37, p1091, see photo on p1095 (below).
  https://archive.org/details/bstj37-5-1091
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AE_Collector

#17
Quote from: unbeldi on October 01, 2014, 10:01:17 PM
It is rather improbably that these were meant to be compatible. These are rather different sets, and although they used the same handset elements, the circuitry was very different, using low current transistor-based transmission circuits.  The dial also is not compatible as it was pulsing at 20 PPS, not 10.

I believe that 5XB or maybe all XBar (and maybe even Panel) will handle 20PPS dials, dont they?

I do see what looks like a different network in the ebay phone as compared to the picture of the 500 with electronic ringer that Paul posted. Now we need to detrmine if this ebay phone is just a 500 with the experimental electronic ringer or is it a specific phone for the Morris electronic exchange trial that also has the electronic ringer.

Is there any chat on the TCI or ATCA lists about it?

Terry

unbeldi

#18
There is a III-62 dated capacitor in this set, while the set itself is dated 1960. I am reviewing the time of the trials. and it seems the trials were ended in 1962, rather than started.

In A Survey of Bell System Progress in Electronic Switching, BSTJ 1965 44(6), pp.937,  W.H.C. Higgins states this:
The system was installed in the central office in Morris, Illinois, early in 1960, and part-time telephone service was given to a small number of customers beginning in June of that year.6 Full-time service began in November of 1960 and continued through January of 1962, at which time the trial was terminated.

The first 1ESS system installation started in 1963 already in Succasunna, which leaves very little time for development if the Morris trial had started/concluded any later.  Morris is credited as the reason for scrapping the tube system and directly influencing the design of 1ESS. However, Succasunna started operating in 1965, two years later, so component design was likely carried out on-site.  Given that the development leading to the Morris system took something like four or five years, there was very little research time for this.

I think, a lot of the developments went on in parallel, as the first time-division multiplexed ESS PBX system started in 1963 (No. 101-ESS).

Bell Labs internally published a book on the Morris system  ''The Electronic Switching System" dated January 1960, and it speaks of the Morris trial in the future tense, but the system, including the trunking arrangements with other systems, the 5XB and the 3CL toll board, are already detailed, and the entire system is customized to the requirement in Morris.

Another description of the system appears in The History of Engineering and Science in the Bell System - Switching Technology.  It also has the trials concluding in 1962.  It credits the beginnings of the Morris design to 1952, and the incorporation of stored program control (SPC) into that system in 1955.  So it seems that all the other trials of the "tone ringer" concept were in preparation of the Morris design.  A prospectus of 1954 already recommended the placement of the system in Morris. The History places the start to June 1, 1960, with 24-hour/day service commencing November 11, 1960. In June 1961, a peak of 434 telephones of 650 main and extension phones were in service. The trial was completed in January 1962.

Picture: Hist.Eng.Sc. Bell Sys - Switching Technology (1982)

unbeldi

#19
So all this doesn't answer the question what a III-62 dated capacitor is doing on this set. It's clearly a WECo part, and the date suggests it being time-period appropriate.

The date of the set leaves no doubt that it was used for Morris, 11-60 is the time when the trial went into full-time mode, but this capacitor is puzzling.

There is also no doubt that all previous sets like this had the only goal of providing a telephone set for the Morris system, no matter where prior testing occurred (Crystal Lake). The cold-cathode tube system was completely scrapped after Morris, but I am wondering whether the same subscriber sets could have been used with the all-transistorized versions leading to the Nos. 101 and 1 ESS.

Dan/Panther

It never ever gets old with this hobby. No matter how long you collect it seems like new stuff pops up all the time. Very interesting phone, and you can tell, ( if it is the way it was originally made and not modified), that it is a prototype of sorts.

D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

unbeldi

#21
Closer examination of the set brings an explanation.
It is hard to see on the original picture, but with image enhancement it is visible that the 425B network in the set was made also made in 1962, after the trial had completed.  The network is bolted to the plate, but that alone may not be of much significance.

This makes it very likely that one of the engineers involved in the trial took the set and converted it, perhaps to operate in a standard loop,  or for another experiment.

paul-f

Quote from: unbeldi on October 02, 2014, 09:46:44 AM
So all this doesn't answer the question what a III-62 dated capacitor is doing on this set. It's clearly a WECo part, and the date suggests it being time-period appropriate.

The date of the set leaves no doubt that it was used for Morris, 11-60 is the time when the trial went into full-time mode, but this capacitor is puzzling.

There is also no doubt that all previous sets like this had the only goal of providing a telephone set for the Morris system, no matter where prior testing occurred (Crystal Lake). The cold-cathode tube system was completely scrapped after Morris, but I am wondering whether the same subscriber sets could have been used with the all-transistorized versions leading to the Nos. 101 and 1 ESS.

Do you have sources for your "no doubt" conclusions, Karl?  The timeline also supports a conclusion that the tone ringing project was developed to achieve a long term cost and/or energy saving goal, independent of Morris or even electronic switching in general.  The trials started years earlier 64 miles from Morris and apparently continued for years after Morris.  There may be even later trials to be found.

The tone ringer generators used at Crystal Lake could could potentially have been installed in any CO.

There may still be some gaps in our knowledge leading up to the release of the S1A tone ringer (501-260-100).
Visit: paul-f.com         WE  500  Design_Line

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unbeldi

#23
Quote from: paul-f on October 02, 2014, 04:02:39 PM
Quote from: unbeldi on October 02, 2014, 09:46:44 AM
So all this doesn't answer the question what a III-62 dated capacitor is doing on this set. It's clearly a WECo part, and the date suggests it being time-period appropriate.

The date of the set leaves no doubt that it was used for Morris, 11-60 is the time when the trial went into full-time mode, but this capacitor is puzzling.

There is also no doubt that all previous sets like this had the only goal of providing a telephone set for the Morris system, no matter where prior testing occurred (Crystal Lake). The cold-cathode tube system was completely scrapped after Morris, but I am wondering whether the same subscriber sets could have been used with the all-transistorized versions leading to the Nos. 101 and 1 ESS.

Do you have sources for your "no doubt" conclusions, Karl?  The timeline also supports a conclusion that the tone ringing project was developed to achieve a long term cost and/or energy saving goal, independent of Morris or even electronic switching in general.  The trials started years earlier 64 miles from Morris and apparently continued for years after Morris.  There may be even later trials to be found.

The tone ringer generators used at Crystal Lake could could potentially have been installed in any CO.

There may still be some gaps in our knowledge leading up to the release of the S1A tone ringer (501-260-100).

No doubt we have gaps in documentation and thinking... and I have not read all that we do have, but the Morris system was already envisioned in 1952, and specifically designated to operate at Morris in 1954, whether there was stored program control or not.  SPC was invented the same year, 1954, and incorporated into the design.  The cross-point switch was going to be cold-cathode tube based in either case. So they knew already in 1954 that they needed to develop a different signaling system
for Morris to be possible technically. If there was any other goal, why didn't they continue the effort with the tone ringer after Morris?  The 1ESS used standard local loops and signaling levels.

PS: the trials actually started before Crystal Lake, with small tests in Georgia.

But certainly there were ideas about tone ringing, as well as tone-based ANI, also using an 8-frequency system before.

Phonesrfun

I don't suppose there is a schematic for the Morris sets?.....  Nah, probably not.
-Bill G

unbeldi

Quote from: Phonesrfun on October 02, 2014, 05:34:22 PM
I don't suppose there is a schematic for the Morris sets?.....  Nah, probably not.

I have not found one.  I have a schematic of the tone ringer though.
I think it is in one of the sources already quoted here.


paul-f

Quote from: unbeldi on October 02, 2014, 04:19:47 PM

If there was any other goal, why didn't they continue the effort with the tone ringer after Morris?  The 1ESS used standard local loops and signaling levels.


There are two topics here -- sets in ringers and conversion of the network to low voltage ringing.

There were later field trials of sets with electronic ringers, such as the set (shown below) covered in a 1968 Bell Laboratories Record article.  They produced the S1A and S1AM tone ringers, as noted above.  As we know today, the industry did eventually replace the mechanical ringers in the sets.

I suspect the Bell System had the vision that electronic ringing was the way of the future but couldn't devise a cost effective way to convert the entire POTS network to low voltage ringing that would get past the accountants and regulators.  We had to wait for the cellular network for that.

It's amazing in retrospect that they accomplished what they did with electronic switching during the infancy of the transistor, when solid state technology was evolving so rapidly.  ISTR reading that by the time Morris was being built the engineers already realized the technology was obsolete.
Visit: paul-f.com         WE  500  Design_Line

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mentalstampede

I'd like to see the date on the dial and if it is indeed a 20 pps dial. I'm thinking that this may have been converted for use on a standard local line after the trial.
My name is Kenn, and I like telephones.

"Progress isn't made by early risers. It's made by lazy men trying to find easier ways to do something." --Robert Heinlein

poplar1

There's a post on the forum about a 1963 Princess with electronic ringer, but I'm unable to find it.
"C'est pas une restauration, c'est une rénovation."--François Martin.

unbeldi

Quote from: paul-f on October 02, 2014, 05:49:31 PM
Quote from: unbeldi on October 02, 2014, 04:19:47 PM

If there was any other goal, why didn't they continue the effort with the tone ringer after Morris?  The 1ESS used standard local loops and signaling levels.


There are two topics here -- sets in ringers and conversion of the network to low voltage ringing.

There were later field trials of sets with electronic ringers, such as the set (shown below) covered in a 1968 Bell Laboratories Record article.  They produced the S1A and S1AM tone ringers, as noted above.  As we know today, the industry did eventually replace the mechanical ringers in the sets.

I suspect the Bell System had the vision that electronic ringing was the way of the future but couldn't devise a cost effective way to convert the entire POTS network to low voltage ringing that would get past the accountants and regulators.  We had to wait for the cellular network for that.

The concept of the original tone ringers was that the signaling was tone-based, not just the audible alert.

The S1A type ringers were quite different, they did not use tone signaling, but standard ring voltage, and generated the tones with an oscillator in the ringer.  These were installed on the wall, not inside a set.

Quote
It's amazing in retrospect that they accomplished what they did with electronic switching during the infancy of the transistor, when solid state technology was evolving so rapidly.  ISTR reading that by the time Morris was being built the engineers already realized the technology was obsolete.

Quite likely so, because the 101-ESS was installed a short time after the Morris trial and it seems inconceivable that the basis of that started after Morris.