Latest #retronetworking acquisition: One of the first commercially available #ISDN video telephones (this unit built in 1992, but I think the model is available 2-3 years longer). Apparently the "Telekom Bildtel 001" was built around a LOEWE MultiTel TV10 BTX terminal, plus an AEG/OLYMPIA codec unit and a TV camera.

@LaF0rge uh you remind me of the time Telecom Italia was running national TV ads about videocalls. I don't think it ever caught up, but maybe in the big cities was more likely.

@LaF0rge 😀👍 Where do you have all that space to test, use, exhibit or store all that technology?

@LaF0rge 👀

@maehw test/use/repair/store at home (bought a house some years back, no kids...). Exhibits are either only virtual (online) or at retro computing events in Germany

@PeterKratz yes, one can find records of those devices being used in the Piazza Virtuale / Van Gogh TV at/around Documenta IX in 1992. You can even find people signing liability disclaimers renting them.

@flameeyes I bought some late 90s video phones from a guy who said he frequently used them back then to call his family in Italy (from Germany)

First step is cleaning everything. Somebody spilled some sugary drink over the keyboard, making most keys sticky (in a sense they remain pushed after depressing them briefly)

The TV part unfortunately doesn't power up at all, just briefly tried that. No LEDs, no usual CRT startup sounds. Luckily the service manual for this part has been uploaded to archive.org. If the codec box has problems, it will be much harder (or even impossible) to debug.

@LaF0rge we're a nation stereotypical for family ties after all.

Hm that reminds me I need to look up a few historical things...

starting to put together some more information and images about this device at https://osmocom.org/projects/retronetworking/wiki/BildTel_001

@LaF0rge Yummy, socketed XC2018!

I found something that looks like a marketing picture that shows this ancient video phone in action:

@LaF0rge @bert_hubert I love how when I was a kid (in the 80s), everyone was striving towards video phone calls as the big frontier to reach in tech, and nowadays video calling is just rote and boring.

https://youtu.be/8_Yz0TT439Q

@Doctor_J_ @LaF0rge By complete coincidence I was looking at OLS2002 photos just now, here is Harald :-)

@LaF0rge Wow that image has written 90ies all over it!

@witewulf @cristianyxen late 80s / early 90s is not easy to distinguish...

@LaF0rge beautifully engineered. It's a shame it's not economically viable to manufacture most devices at this level of quality now. I'm always blown away when I open up old Tektronix or HP test gear, which was typically also aircraft rated.

@LaF0rge It also seems like this device runs in 50 Hz mode, so the crystal on the BTX decoder would be 24 MHz instead of the typical 28,8MHz

@casandro as far as I can tell this BTX decoder has two XTALs: 14.74 + 17.734 MHz. The strings int he EPROM image look very much like BTX to me (Mitbenutzerkennung, ...) and not like anything ISDN Videophone related. My guess is they really just use the BTX decoder as a terminal.

@LaF0rge Is it a special TV or could you connect any to the SCART?

@LaF0rge you must get that working and online so you can 'facetime' someone :-D

@zxm @LaF0rge In fact, a bridge to Facetime/Skype/Teams/... would be hilarious.

@1000millimeter @zxm the actual goal is interworking with other (later) isdn video phones such as the T-View 100. It might be that this Bildtel 001 predates the H.320 standard and hence would not Interoperate with any other ISDN video phone model.

@1000millimeter the video signal can certainly be shown on any TV or recorded on VHS via scart. However, the UI od the phone is apparently using the BTX decoder in that special TV set.

@LaF0rge Does it double use as a BTX Phone? If no you certaainly are right about the GUI. However if the TV has an issue, maybe for first tests a combination of BTX soft decoder and standard TV could work?

@LaF0rge In case you didn't recognize the part number: that was the second FPGA model made by Xilinx. It had 100 Configurable Logic Blocks (CLB) while the XC2064 had only 64.
https://commons.wikimedia.org/wiki/File:Xilinx_XC2018_LCA.jpg

@LaF0rge Just checked out your updated wiki post about it.
They keyboard unit is only connected via TAE?
My guess is: this is just for phone audio. the unit has a socket that looks like DIN - I woud assume it will be connected to the TV via a DIN cable with that.

@1000millimeter the keyboard/phone unit has a fixed attached cable with TAE plug that likely indeed behaves just as phone. It does however also have another proprietary socket for which I have no plug or cable :( I guess that's the actual keyboard output.

@1000millimeter when plugging the TAE-F into a phone line, the phone receiver works as a phone. Keyboard doesn't seem to do anything, not even dialing is possible. Guess it only powers via that unknown "C" connector

@LaF0rge @1000millimeterdoes that "tae" has two times four connections?

@LaF0rge From the photo in the wiki I would have hoped it's a standard DIN connector. This connector looks like some TAE relative, will be complicated to get one.
However, my guess would be it connects to one of the connectors on the TV. (Which one does connect to the V.24 of the Codec unit?) If someone has a "normal" Multitel, it could be possible to figure out pinning.

@LaF0rge No dialing, not even with the numerical keyboard on the right? I would have expected it to work.

@1000millimeter nope, numerical keypad on the right doesn't work with TAE-attached-only. However, I meanwhile realized that I do have the matching cable to connect the TV/BTX unit with the keyboard connector "C". It's fixed-attached to the TV on the other end (doh!).

@LaF0rge This way, at least it can't get lost

@LaF0rge This is an interesting monitor, by the way. The same model/base system is used as a monitor for the Multitel 2 BTX terminal and it was also sold as a standard TV set (labeled as LOEWE if I remember correctly).

@LaF0rge Apparently, this "first generation" of ISDN videophones features three models (including your Bildtel 001). These three models were (later?) marketed as "Claudia Q", "Christa R" and "Lisa C".

@LaF0rge Oh boy, I should have read your first post before posting mine.😀

@LaF0rge One of the phones is featured in this video: https://www.youtube.com/watch?v=1lYFr-C_SKg&t=14m30s

@LaF0rge If one looks closely, the monitor as well as the phone part are labeled with stickers, just saying "Bildtelefon".

took some better pictures of the open Bildtel 001 (1992 ISDN video phone) Codec Unit: https://osmocom.org/projects/retronetworking/wiki/BildTel_001#Codec-unit #retronetworking #isdn