My SC 1543

[andre_janew]

I have done some work on the SC 1543 I recently purchased on eBay.  I have added a line cord and changed the handset cord.  The handset cord I am using is for a 1972 WE 500 set.  It looks similar to the one that came with the SC phone, but the coils are slightly larger in diameter.  I have been using a soldering iron to melt black plastic where there is a missing piece in one corner of the case.  I'll post some pictures later if anyone is interested.  ( I'm sure there will be some interest!)

http://www.ebay.com/itm/131466425640

[andre_janew]

The first picture is of the line cord I am using along with the 4-prong plug.  I have an adapter so I can plug it in to a modular jack.  The next is a picture of the start of the repair I am making to the case. 

[andre_janew]

The only place where I can find a date on this phone is on the network.  There is not one date on the transmitter or the receiver.  There is however an SC #4 mark on the inside of the case.

[andre_janew]

Is it my imagination or do the transmitter and receiver elements look the same as those on a Western Electric 500 set?  The handset  and case are definitely Stromberg Carlson.     

[HarrySmith]

Cool! How's the repair on the case coming? I am always interested in different ways people come up with to repair plastics. the soldering iron is a new one on me. It looks like a good start in the last picture.

[andre_janew]

I got a bit more filled in.  I did a bit of sanding as well.  It isn't quite the same shape as it once was.  I'll post some more pictures later to show you what I mean.  I got the idea of using a soldering iron from a Corvette owner.  If it works with plastic car bodies, maybe it would work with plastic phone cases!

[unbeldi]

Is it my imagination or do the transmitter and receiver elements look the same as those on a Western Electric 500 set?  The handset  and case are definitely Stromberg Carlson.   

If it passes the Duck Test, there is probably a reason.

Yes, all of the independent telephone makers at some point benefitted from the licensing arrangement that WECo had to submit to and they all produced equipment very similar if not identical in appearance and function.

At some point the 1543 telephones received a 425B-type network, part number 210640-RA, which had identical electrical performance and function as the Bell equipment. It only looked differently under the hood, in fact looked just like the earlier Stromberg-Carlson networks.

Consequently they also used the new high-efficiency transmitters and receivers of the 500-type in the handsets they produced.

[mdodds]

Andre,
I too am resuscitating an SC phone, a 2-1553-WA which unbeldi has helped me with tremendously in another post. I have the same handset, which is noticeably different than a WE (primarily it's narrower), and mine also has the transmitter and receiver that look just like the WE versions, as well as having the 210640-RA network.
I noticed from your photos, that, like mine the plastic transmitter cup seems a sloppy fit in the handset, like it's not really made for that handset. I wonder if SC decided when they went with the WE style transmitter, they just said "close enough" and used the WE transmitter cup?

[G-Man]

Is it my imagination or do the transmitter and receiver elements look the same as those on a Western Electric 500 set?  The handset  and case are definitely Stromberg Carlson.     

The handset shown was not originally used with a S.C. 1543 instrument.

The 75555 transmitter is a clone of the Western Electric T1 and not original to your set. Instead, it was manufactured by ITT. The photo of the receiver is too poor to i.d., but both Stromberg and ITT initially used Western Electric U1 units for a number of years on their "G"-type handsets until they could manufacture their own; even then, they continued for a number of years to source the 44A varistor since WECo pretty much was the only manufacturer able to source the raw material and produce them in sufficient quantity.

[G-Man]

Hmm...
Perhaps I'm missing something but the schematic for the 1543 seems to show that its network is NOT self-compensating and is NOT the equivalent of WECo's 425.

[G-Man]

Here is the schematic for the S.C. 1543W version which included a self-compensating network which was roughly the equivalent of WECo's 425 networks.

[mdodds]

G-man,
That photo of the receiver and transmitter you posted is the one I remember from my previous SC phones and was expecting to find on mine, but I didn't. My physical handset is definitely a Stromberg Carlson (the handle portion on my WE G's measures about 1-1/2" across the back, the SC measures about 15/16"), but internally it appears to be made for the WE clamp style cord....no place for a screw. hard to tell from Andre's photo, but I think he has the same handset I do. Maybe it's some sort of hybrid before they started using the G style as in their later phones?
I also noticed that Andre's network, while I can't make out the whole number, is not the same one I have, which is the self-compensating one.
Dealing with and figuring out all these little differences is part of what makes this stuff so addicting!

[andre_janew]

I do have pictures of the sides of the network.  Definitely not a WE 425 network.  It must be a Stromberg Carlson network.  There is a diagram in this forum for it.  It is slightly dirty, but legible.   

[andre_janew]

Here are some pictures of the case that I am  repairing.  The repaired area is of a slightly different shape than the original.  Even so, it does look better than the hole that was there before.  (Well, I thinks it does!)

[unbeldi]

I do have pictures of the sides of the network.  Definitely not a WE 425 network.  It must be a Stromberg Carlson network.  There is a diagram in this forum for it.  It is slightly dirty, but legible.

When I wrote that the 1543 received a 425-type network, this means that it duplicates the electrical function of the 425, not that it looks the same, as I wrote in another thread as well. All networks in the 1200-series, 1400-series, and the 1500-series used the same physical form factor for the network, but were different internally.