Siemens TT desk phone

[AdamAnt316]

Hello everyone. I found a Siemens touch-tone desk phone at an antiques mall today. It looks similar to other Siemens phones I've seen, except that it has four extra buttons whose purpose I'm not sure about at the moment. Its line cord has four wires on the end which appear to be colored brown, green, white and yellow. Does anyone know how this would cross to US wiring? Also, any idea what the four extra buttons do? I assume the round one is a flash button, as typical for European phones, but I'm not sure about the rest. Finally, any idea what the correct model # is? I've seen Siemens phones bearing FeTaP numbers, but the sticker on the bottom of this one just bears three long numerical codes. Anyway, thanks in advance!
-Adam

[countryman]

I found 2 entries in a german forum:
https://www.wasser.de/telefon-alt/forum/index.pl?job=thema&tnr=100000000004878&seite=28&begriff=&tin=&kategorie=3-
https://www.wasser.de/telefon-alt/forum/index.pl?job=thema&tnr=100000000008766&seite=11&begriff=&tin=&kategorie=

It seems like these phones were only used in combination with private Siemens exchanges and therefore do not have "official" labels like "FeTap...". The white buttons triggered functions programmed inside the exchange: callback, redial, call forwarding, speed dialing. They just send tones like the number buttons, on some keypads these tones are attributed with the letters A-D.
The round button should be a flash button, but I'm not sure about the flash duration. Earlier euro phones rather had Earth buttons, but these should have been obsolete from the eighties on.
German phones usually use brown and white as a/b (tip/ring in US notation?)

[AdamAnt316]

I found 2 entries in a german forum:
https://www.wasser.de/telefon-alt/forum/index.pl?job=thema&tnr=100000000004878&seite=28&begriff=&tin=&kategorie=3-
https://www.wasser.de/telefon-alt/forum/index.pl?job=thema&tnr=100000000008766&seite=11&begriff=&tin=&kategorie=

It seems like these phones were only used in combination with private Siemens exchanges and therefore do not have "official" labels like "FeTap...". The white buttons triggered functions programmed inside the exchange: callback, redial, call forwarding, speed dialing. They just send tones like the number buttons, on some keypads these tones are attributed with the letters A-D.
The round button should be a flash button, but I'm not sure about the flash duration. Earlier euro phones rather had Earth buttons, but these should have been obsolete from the eighties on.
German phones usually use brown and white as a/b (tip/ring in US notation?)

Thanks for the reply! I'll have to run those forum threads through Google Translate. Any idea what the extra tones used are? Wondering if they used a setup similar to the AutoVON dials. I'll have to connect it to my RS Telephone Tester, and see what (if anything) its display indicates when the extra buttons are pressed.

Thanks for the color code info! I found some data on the subject on this page, which did seem to list white and brown as the line wires. It also lists yellow as a ground connection, and the green wire as being used for an 'external bell'. How should I connect these wires, if at all? I know in the US, the yellow ground wire in older Western Electric phones sometimes has to be connected in parallel with the green line wire in order to get the phone to ring, but I have no idea if that might be the case with a phone like this. Also, what might a connection block for a phone like this have looked like? Again, thanks!
-Adam

[countryman]

The pic shows a cord like it would be used forthe phone "here" (I suspect). The rectangular thing is a AS4 connector. AS = Anschluss-Stecker, Access-Plug. From the sixties to the eighties it was used on both ends of the cord. German phones usually were hard wired to a "VDo" (Verbinder-Dose, Connection Box) on the wall where the AS4 was plugged in and then covered with a sealed cap which only Deutsche Bundespost techs should remove, same on the phone side. ADo (Anschlussdose, Access-Socket) plugs also were available but not used much in private houses (maybe costed extra???)
https://www.komos.de/wp-content/uploads/2009/07/ado__vdo.pdf

Since 1987 the TAE (Telekommunikations-Anschluss-Einheit, Telecommunications Acess Unit) is used, still even for DSL-only service. The first plug in the house still is property of the provider, but nobody controls this any more. Only the 2 lower-left contacts on the 6-pole TAE plugs are used any more (a/b).
The green and yellow wire are also not used any more. Extra bells are completely out of style (while might still work on this phone) and Earth buttons are obsolete except someone might run a very old non-solid-state private exchange. Pre-1975 maybe?
The extra buttons should work just like in the wikipedia article: https://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling, where Autovon is also mentioned.

[AdamAnt316]

The pic shows a cord like it would be used forthe phone "here" (I suspect). The rectangular thing is a AS4 connector. AS = Anschluss-Stecker, Access-Plug. From the sixties to the eighties it was used on both ends of the cord. German phones usually were hard wired to a "VDo" (Verbinder-Dose, Connection Box) on the wall where the AS4 was plugged in and then covered with a sealed cap which only Deutsche Bundespost techs should remove, same on the phone side. ADo (Anschlussdose, Access-Socket) plugs also were available but not used much in private houses (maybe costed extra???)
https://www.komos.de/wp-content/uploads/2009/07/ado__vdo.pdf

Since 1987 the TAE (Telekommunikations-Anschluss-Einheit, Telecommunications Acess Unit) is used, still even for DSL-only service. The first plug in the house still is property of the provider, but nobody controls this any more. Only the 2 lower-left contacts on the 6-pole TAE plugs are used any more (a/b).
The green and yellow wire are also not used any more. Extra bells are completely out of style (while might still work on this phone) and Earth buttons are obsolete except someone might run a very old non-solid-state private exchange. Pre-1975 maybe?
The extra buttons should work just like in the wikipedia article: https://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling, where Autovon is also mentioned.

Again, thanks! The wires at the end of the line cord on this Siemens phone have what looks to be the equivalent of the individual connectors inside the clear AS4 plug you pictured, but not within any sort of holder. Not sure if that's typical for this sort of phone; it reminds me more of early hard-wired desk phones from the '30s to the '60s. Would the earth lead be necessary for the Flash button to work? Should I connect it in parallel with the green terminal, or just leave it hanging?

Also, thanks about the info on the extra buttons. I wasn't sure if the tones would be the same as on other 16-button dial pads. Once I get the phone rigged up to a modular plug, I'll see what it does with the dialing test on my aforementioned telephone tester.
-Adam

[countryman]

Maybe the AS4 plug broke or someone opened it intentionally to acess the individual wire connectors.
A flash signal is a short interruption of the actual phone line itself, and can often be generated by hitting the headset plungers briefly. There is no other wire involved. Leave them unconnected.

According to the before mentioned forum entries this "should be" a keypad generating all 16 possible dual tones , 1...0, *, #, A..D.
Later german phones like the Tel 01 LX
https://www.wasser.de/telefon-alt/datenbank/inhalt.pl?tin=&kategorie=1000020&begriff=telefon
also had 16 keys but 4 of them did not generate tones. They activated functions like redial or speed dialing inside the phone itself instead.

[AdamAnt316]

Yet again, thanks! I have a number of European phones around here, but most of them are rotary dial. Pretty much the only other Euro touch-tone phones I have around here are a couple of Bang & Olufsen Beocoms, which are much newer than this Siemens, and have several fancy features built-in. As for the line cord, there doesn't seem to be any evidence of the AS4 connector shell having been present at some point, but who knows. I'll probably just rig up the open contacts to spade connectors so I can attach the appropriate wires to a 42A-style connection block.
-Adam