1964 Antique MODEM Live Demo

Circa 1964 Livermore Data Systems "Model A" Acoustic Coupler Modem, live demonstration.




Q&A: http://phreakmonkey.com/index.php/arc...

Background: This modem was given to me ~1989 by the widow of a retired (IBM?) engineer. Computerhistory.org has a Model B dated 1965, and I've seen a ~1967 Model C written up in a magazine. (Interestingly, incorrectly identified as being only 110 baud.)

Even better than seeing it in a museum, I decide to hook the trusty Model A up and make it talk to something. After some trial and error, I manage to get it to talk to a terminal server at work and use it to connect to a linux box. It's ALIVE! So, 45 years after it's creation, this antique modem gets to send data to and from the modern Internet.




Enjoy!
- K.C.

• Category

  Science & Technology

[phreakmonkey]

Venkat, I accidentally clicked [Remove] instead of [Reply] to your comment!

What you're looking for is "Bell 103" modulation. It is a Frequency Shift Keyed (FSK) modulation type, used in shortwave radio applications. Two sets of tone frequencies, named "originate" and "answer", allowing for duplex communications. (A similar 300 baud modulation type is V.21, using different tones.) A search for "Bell 103 modulation" and "shortwave" will probably find the details for you. Good luck and have fun!

[CamiloSanchez1979]

So when you made the call what did you connect to? a dial up service? I am confused in that part.

[phreakmonkey]

Essentially, yes. It was a dial-up terminal server at my office, from which I was able to connect to a temporary Linux host in my lab.

[tombraider200571]

... fuck... is there anything slower then kilobytes?.. cause that what its workin on.

[phreakmonkey]

yep. 300 bits (not bytes) per second. Since RS232 uses 1 start and 1 stop bit per 8 bit 'byte', that's an effective data rate of "30 bytes per second" or, to use the parlance of our times, 0.0292 kilobytes per second. ;)

[thefamilyk]

Porn must have been very difficult

[phreakmonkey]

The d-subminiature 'DB-25' connector was created by ITT 12 years earlier in 1952. The RS232 serial communication standard originally recommended, but did not require, the DB-25 connector. It was published in 1962, but had existed without being a written standard for a few years prior.

[J. A. Restucci]

Great video, reminded me so much of my Hayes Smart Modem (1200 baud) back when I ran a BBS in the late 80's - brought back memories, thanks for sharing!

[Helper666ggg]

...still faster than the AT&T or Sprint network...

[Xunkun]

Would you be able to tell me why, even late-model modems of the 90's, the dial tone and all that buzzing, beeping, and hissing had to be *phsyically* audiable?

[Chuckles DeClown]

@thecooldude9999 I don't think that's an IBM thinkpad, no thinkpad in existence has had a grey panel on the side of the screen

[thecooldude9999]

ibm thinkpad

[Ubiquitous69]

Reminds me of watching the movie Wargames in my childhood (David also had an acoustic modem) and wishing I had such cool hardware.

[jcp012000]

This is cool!

[KairuHakubi]

you.. you literally put the phone handset on it... my god..

i think the only thing more surprising is the fact that it makes the same familiar dialup noise. That is one OLD noise

[Alexander Weps]

They don't build them as they used to.

[linkdude64]

That's so cool to see a text-only browser in use with the Legacy hardware. I'm a youngin' who's into IT and love seeing stuff like this. That modem is a true work of art. Thanks for uploading!