Please help with Stromberg-Carlson 1543

[holdthephone]

Looking for some information on a Stromberg-Carlson telephone I rescued from an abandon factory/warehouse in northern New Jersey. It is dated 11-58 model # is TD-80 72J-60. It looks like the 1543 cut corner model however, It doesn't say 1543 anywhere, it does not have an alphanumeric dial plate and it has a straight, not coiled handset cord. would like to find out what the purpose of this model was. I am told the ringer configuration matters. Not sure how to carefully remove the cover on one of these though?? Thank you for your help!
Let me see if I can post some pics...

[LarryInMichigan]

Welcome to the forum   Your phone looks like an early SC1543 to me.  I do not believe that I have seen code numbers like the ones on yours before. 

The shell is held by one set screw on the back near the bottom.  Loosen the screw and then lift the shell from the back.  It will hinge on a tab in the front of the phone.

Most of these phones were shipped with frequency ringers which will ring only for a specific frequency of ringer voltage.  This scheme was used for party lines.  Seeing pictures of the insides of your phone might help us determine if there is anything unusual about this phone and what kind of ringer it has.

Larry

[G-Man]

Looking for some information on a Stromberg-Carlson telephone I rescued from an abandon factory/warehouse in northern New Jersey. It is dated 11-58 model # is TD-80 72J-60. It looks like the 1543 cut corner model however, It doesn't say 1543 anywhere, it does not have an alphanumeric dial plate and it has a straight, not coiled handset cord. would like to find out what the purpose of this model was. I am told the ringer configuration matters. Not sure how to carefully remove the cover on one of these though?? Thank you for your help!
Let me see if I can post some pics...

I believe you have a model that was intended to be used with a S.C. Dialmaster  PAX (or similar) and will not work on the PSTN.

At the moment I forget what the differences are but I seem to remember it requires three-wires and perhaps it also uses a low-voltage ringer.

There may be other members on the list that recall the exact details.

[dsk]

Welcome.
That one is a nice one.
Could be interesting to look inside.
it will always be possible to make it adapted to regular network, but I would not recommend to modify more than reversable to original state.

dsk

[LarryInMichigan]

I believe you have a model that was intended to be used with a S.C. Dialmaster  PAX (or similar) and will not work on the PSTN.

That sounds quite plausible.  I am curious to see the insides.  If it is anything like a Kellogg Select-O-Phone, most of the internal parts will need to be replaced to make it work on a POTS line.

Larry

[holdthephone]

Thanks for everyones help! I suspected it was configured for some kind of PAX being that it was found in an industrial setting and because the dial card has a "1" on it and under that was a "97". Unfortunately the building has probably since been demolished and any other part of the system is gone. The phone wasn't connected to anything when found anyway. I removed the cover today and took some pics. It has three wires coming out the back green, red, yellow. so I can assume that this ringer will not work in my home  Pretty clean inside otherwise! Even the dial card cover is in one piece! I think it will display nice.    -Mo

[G-Man]

I believe you have a model that was intended to be used with a S.C. Dialmaster  PAX (or similar) and will not work on the PSTN.

At the moment I forget what the differences are but I seem to remember it requires three-wires and perhaps it also uses a low-voltage ringer.

There may be other members on the list that recall the exact details.
[/quote]

To update the information regarding your TD-80, this is from the TCI archives...

>>>>I believe I have a Dial-X tech manual of perhaps 20-30 pages. It's not
currently readily accessible. I never had much interest in it so I
never looked at it carefully, but I recall it having diagrams of some
sort and photos.

>
>While I don't have a copy of the print, the TD80 was a SC1543 with a little
>different dial and a buzzer instead of a ringer. The dial closed a set of
>pulse contacts instead of opening them. There may be additional
>differences but I think the network and other parts were the same.
>
>These were used in the SC "Dial X" and "Dial Master" systems. The Dial
>Master could accomodate I think 100 stations while the Dial X had three
>distinct systems. There was a 10 line, single link, 20 and 40 line multi
>link systems. The telephone sets were labeled in later years as the TD
>4500 Desk, TD 4510 Wall set. All sets required three leads or a triplex
>type JK (IW).

[LarryInMichigan]

It looks mostly like a normal phone, but the guts of the network block could be different.  Also, the lack of a ringer capacitor might suggest that the ringer voltage was supplied through different wires.  Can you tell if the dial pulsing contacts are NC or NO?

Larry

[holdthephone]

The contacts look n.o.

Thanks, -Mo

[LarryInMichigan]

On a normal dial, the pulsing contacts will be NC.  The shunt contacts will be open when the dial is in its rest position and closed otherwise.

Larry

[G-Man]

The contacts look n.o.

Thanks, -Mo

>The dial closed a set of
>pulse contacts instead of opening them.

The comments pasted from the TCI list have already established that the dial on TD-80s have normally open contacts (n.o.).

The consensus appears to be the instrument can be modified for use on the pstn if the audible signal and dial differences are addressed.

A close-up of the bell and dial may be helpful. If the bell is in fact d.c., it will have to be replaced. It may be possible to replace only the ringer motor assembly instead of the gongs, etc.

I'm not sure but  you may be able to re-arrange the pulsing contacts to operate in the n.c. Mode. While the network may be different from their standard pstn network, that may not make much difference for this application.

If the ringer/buzzer is d.c. operated, S.C. may have deleted the ringer capacitor inside of the network, but that will not be a problem since you can easily add a capacitor from Rat Shack.

[LarryInMichigan]

It looks like an AC ringer from here.

Larry

[G-Man]

It looks like an AC ringer from here.

Larry

From what little we can see of it, yes it does. But since we can not see the ringer motor assembly we can not be sure so that is the reason I suggested close-up photos of the entire assembly.

[G-Man]

The contacts look n.o.

Thanks, -Mo

>The dial closed a set of
>pulse contacts instead of opening them.

The comments pasted from the TCI list have already established that the dial on TD-80s have normally open contacts (n.o.).

The consensus appears to be the instrument can be modified for use on the pstn if the audible signal and dial differences are addressed.

A close-up of the bell and dial may be helpful. If the bell is in fact d.c., it will have to be replaced. It may be possible to replace only the ringer motor assembly instead of the gongs, etc.

I'm not sure but  you may be able to re-arrange the pulsing contacts to operate in the n.c. Mode. While the network may be different from their standard pstn network, that may not make much difference for this application.

If the ringer/buzzer is d.c. operated, S.C. may have deleted the ringer capacitor inside of the network, but that will not be a problem since you can easily add a capacitor from Rat Shack.

In case you have not already come across documentation for the 1543-series, here is a link to a handbook containing a number of schematics and details that may assist you in converting your TD-80:
http://www.telephonecollectors.info/index.php?option=com_docman&task=doc_details&gid=3481&Itemid=2


                                       

[GG]

Looks to me like a 60-Hz frequency ringer:

The clapper rod has a small clapper/weight on it that is attached to it with a set-screw.  Set screw mounting usually indicates a frequency ringer and small size of clapper/weight indicates higher ringing frequency.

The ringer itself seen in the second photo shows the number 72 J 60, which I'll guess means "ringer type 72 J, frequency 60 Hz." 

However do NOT connect that ringer directly to house current AC.  Instead try connecting it to 24 volt AC from a 1A2 power supply if you have one around, and see what happens.

It may be possible to make this phone ring by using an AC to AC power supply, and a relay (plus capacitor and zener diodes) activated by ringing current on the phone line.

Re. the dial:

The Select-O-Phone variant of the Kellogg 10-G dial has normally open contacts, and the metal part in which the impulse cam rotates, or the impulse cam itself, is designed in a manner that cannot be converted to give a normally closed operation. 

SC dials of that vintage have a very similar impulse mechanism to Kellogg 10-G dials, so it is entirely likely that if they are normally-open, they will not be possible to adjust.

However!, you can easily find 1543s in crappy condition on Ebay, and transplant the relevant components, thereby preserving as much of your older one as possible.