Circa 1964 Livermore Data Systems Model A Modem
Posted by kc on May 28th, 2009
So I was going through some old stuff in my garage and I found this antique modem that I’ve had since I was a teenager. Turns out it’s a Livermore Data Systems “Model A”. I decided to hook it up and see if it works, and I made a YouTube video in the process:
I’ll get around to posting some better photos of it this weekend, I promise!
May 28th, 2009 at 10:00 am
Fantastic. Good protocols will stand the test of time. Even at 300 baud…
May 28th, 2009 at 10:24 am
I remember using a 1200/75 baudrate modem for accessing viewdata services in the UK in mid-80’s
Heady days
Matt
May 28th, 2009 at 1:35 pm
Nice! thanks for posting this. I remeber seeing an older transducer modem growing up but I never saw one in action.
thanks for sharing.
May 29th, 2009 at 1:29 am
I had the pleasure of attending a talk you gave at DEFCON. And then a fan of mine sent me a link to this! I’ve spread the word and it looks like you’re getting a lot of hits for it. Take care of that thing!
May 29th, 2009 at 11:41 am
That’s pretty amazing. The USB converter voltage issue had me gobsmacked. I had no idea the original modulation was so simple.
Have you tried seeing how painful a proper PPP or SLIP session would be? Until you’ve done that, the modem hasn’t technically connected to the Internet.
Also, is the speed limit due to the modulation? Have you tried driving it at 1200 or 2400 baud? Obviously any multi-bit baud won’t work, and my suspicion is that the negotiation would fail unless you were to hack the modem to emit a different carrier tone, which obviously is not something that should be taken lightly with such a beautiful, old piece of hardware.
May 30th, 2009 at 11:38 am
This demo was a thing of beauty, as is that modem! I’d like to see dovetail joinery return to technology cases.
My first modem (mainly because I was really cheap) was a Webcor 300-baud unit, so the connection speed seemed eerily familiar to me.
Thanks.
May 30th, 2009 at 12:46 pm
About 20 years ago I was in the clerk’s office of the York County, Va., Circuit Court. There I saw a pale green Bakelite box about 18″ long, marked “MODEM”. I didn’t inspect it, but I imagine it was a military surplus modem from the ’60s or ’70s. They may still have it, if you’d care to check it out.
May 30th, 2009 at 5:51 pm
Thanks for doing this video! I was feeling pretty cutting edge with my 300 baud modem in the late ’70s. I can’t believe this device had already been in existence for 15 years at that time. The more amazing find is that the modulation protocols hadn’t changed. I’m blown away that you were able to make this work with relatively modern equipment. Take really good care of that modem! It’s good to remember our tech roots
May 31st, 2009 at 4:43 am
Thanks for posting this up. It’s great to see ancient computer devices in action!
May 31st, 2009 at 8:34 am
Cool device! I’ve never seen, how analog modems works
May 31st, 2009 at 4:17 pm
Casey,
This is an awesome video. Thanks so much for taking the time and effort to share with us. As someone who is deeply interested in computer history, this was incredible to watch.
Thanks again.
May 31st, 2009 at 4:59 pm
Very cool, K.C. Thanks for sharing that relic with us!
Reminds me of the setup I had to lug around with me during my internship as a reporter during college–suitcase-sized “laptop” with a separate modem that wasn’t much different than that one, though smaller.
And, you’ve reminded me why I never got too heavily into BBS’s. I was never patient enough!
June 17th, 2009 at 8:06 am
Congratulations! It is fantastic, very good! XD
Info Tecki – Brazil Force!
Informação e Tecnologia a Kilo!
June 21st, 2009 at 9:52 am
It’s amazing how long modems have come since then. ADSL2+ and DOCIS 3.0 modems transferring data multiple times larger than the grandfather modem!
June 21st, 2009 at 3:44 pm
Just saw the video on ‘64 modem.Fantastic…….
August 18th, 2009 at 9:54 pm
I remember using an acoustic MODEM a few years ago when I lived in an unserviced area, running through a bag phone (remember those?)… This is all to familliar to me. At least I’m not the only one who has used one of these units in the last few years.
That, by the way, is a beautiful piece of equipment you’ve got there, excellent workmanship.
September 2nd, 2009 at 7:23 pm
I loved the video! It brought back memories of my first self-made 300Baud acoustic coupler — unfortunately, we had birds in the living room, and whenever they opened their mouth, the connection would drop. So I had to wait until 1200 Baud became available, where the galvanic separation was done with a transformer, and not air and sound. Plus, 1200 was blazingly fast! You wouldn’t want to go back!
January 30th, 2010 at 8:31 pm
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