50th Anniversary of "Tennis for Two"

[Ugly]

All,

I'm hoping to recreate "Tennis For Two" as it was originally implemented at Brookhaven National Laboratory. If anyone is familiar with the components and schematic conventions of the era, your help would be greatly appreciated.

[Thorn]

Re: 50th Anniversary of "Tennis for Two"

All,

I'm hoping to recreate "Tennis For Two" as it was originally implemented at Brookhaven National Laboratory. If anyone is familiar with the components and schematic conventions of the era, your help would be greatly appreciated.

The schematic conventions are no different than today's. However, that page has only two out of three schematic sheets needed. In particular, the gates circuits are all missing.

[streaker69]

Re: 50th Anniversary of "Tennis for Two"

Thorn,

Don't you still have the original copy that you wrote on the back of a cocktail napkin that you gave to those guys before they built it?

[Thorn]

Re: 50th Anniversary of "Tennis for Two"

Thorn,

Don't you still have the original copy that you wrote on the back of a cocktail napkin that you gave to those guys before they built it?

Uh, no.

Seriously, the fun part was seeing Ralph Baer on the History page of that site. Mr. Baer designed the first consumer video game platform, the Magnavox Odyssey. He also wrote the Foreword for Joe "Kingpin" Grand's book Game Console Hacking, to which I contributed.

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

I've been unable to find anymore than those pages. Of course now that you've mentioned an additional page, I see that they're numbered one and two respectively. I wonder if anyone is up to the task of recreating the magic without the 3rd page.

Of course, knowing the resourcefulness of this bunch, I wouldn't be surprised to have the originals turn up at the Riv.

[Thorn]

Re: 50th Anniversary of "Tennis for Two"

I've been unable to find anymore than those pages. Of course now that you've mentioned an additional page, I see that they're numbered one and two respectively. I wonder if anyone is up to the task of recreating the magic without the 3rd page.

Of course, knowing the resourcefulness of this bunch, I wouldn't be surprised to have the originals turn up at the Riv.

Yes, plus they're also marked "1-3" and "2-3"

I misspoke about the "gates". Those triangles aren't gates, but amplifiers. A typical signal amplifier built out of discrete components circa 1958 would have been something like on this page: http://www.st-andrews.ac.uk/~www_pa/...pt5/page1.html But even recreating those, there seems to be some information missing. For example, on page 2, there are six inputs marks as "to output of computer." I'd guess it's some sort of TTL output, but what exactly?

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

Yes, plus they're also marked "1-3" and "2-3"

I misspoke about the "gates". Those triangles aren't gates, but amplifiers. A typical signal amplifier built out of discrete components circa 1958 would have been something like on this page: http://www.st-andrews.ac.uk/~www_pa/...pt5/page1.html But even recreating those, there seems to be some information missing. For example, on page 2, there are six inputs marks as "to output of computer." I'd guess it's some sort of TTL output, but what exactly?

Those are listed in the notes on page 2 detailing their assignments as ball, net and court horizontal and vertical, which are accounted for on the right side of page 1.

I have a feeling page 3 has all the amplifier circuits as well as additional power circuits for the other inputs on there like +/-75V, 60V DC, +DC, etc.

I'm actually going to call Brookhaven tomorrow and see if I can convince them to pull the schematics out of the Raiders of the Lost Arc type gov warehouse they're probably stored in so we can give them a go.

Here's hoping.

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

Well, I've received a response from the administrator of the site where I found the schematics. He was directed to them by an author who had the links sent to him by Higginbotham's son.

The archive.org links he provided for the source of his images are no longer in the archive and Higginbotham's son suggested that the original blueprints may not be available any more.

I'm going to try the lab just the same, but if we can't get the last page of the diagrams, is anyone willing to try and recreate the missing circuits in a manner consistent with what is present?

I realize those 10 amplifier sections are going to be the most complex parts of the circuit, but it seems a shame to walk away from a challenge like this.

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

I called the lab and spoke to Regina in the visitors center. She's passed along my request along with the link to Brookhaven's write-up on tennis for two to the instrumentation lab.

http://www.bnl.gov/bnlweb/history/higinbotham.asp

Per that page, the bulk of that analog computer was 10 operational amplifiers that could be configured to simulate ballistic motion. Being that it was made in 1958, they're pretty much guaranteed to be double tube op-amps.

I've also found the name of one of his collaborators on the project: Robert V. Dvorak

His grandson posted in a discussion about tennis for two earlier this year and mentioned that he thinks he has some of the original schematics around. I've asked the site's operator to contact him on my behalf.

[Thorn]

Re: 50th Anniversary of "Tennis for Two"

Per that page, the bulk of that analog computer was 10 operational amplifiers that could be configured to simulate ballistic motion. Being that it was made in 1958, they're pretty much guaranteed to be double tube op-amps.

Could be, there was a lot of mixed tube and transistor circuits back then. If it's true, replicating the circuit might not be hard to do, but getting the tubes themselves may be difficult and costly.

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

Problem is, until we have the circuit re-created, I would have no idea which tubes to find. I know several people around town that have older electronics on hand and I'm sure plenty of DefCon folks have relevant components. Let me know if you come up with any ideas, I'll keep working on getting the rest of the schematic.

[Thorn]

Re: 50th Anniversary of "Tennis for Two"

Problem is, until we have the circuit re-created, I would have no idea which tubes to find. I know several people around town that have older electronics on hand and I'm sure plenty of DefCon folks have relevant components. Let me know if you come up with any ideas, I'll keep working on getting the rest of the schematic.

I'll ask my father. Dad was an EE for Raytheon in the 1950's before he moved on to other things. He still talks about using Nixie tubes for digital readouts.

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

If anyone else cares to look into finding the schematics, It was designed by William (Willy) A. Higinbotham, built by Robert V. Dvorak and the schematics were created by Alexander Elia.

Higinbotham died in 1994 but his grandson had contact with authors detailing the history of the game, Dvorak died in 1969 but his grandson posted to this discussion about his grandfather's involvement:
http://simondvorak.com/2004/12/17/robert-v-dvorak/

I haven't found any further mention of Elia yet.

[Ugly]

Re: 50th Anniversary of "Tennis for Two"

I've contacted Brookhaven National Laboratory public relations and was directed to an engineer who has been tasked with recreating Tennis for Two for it's 50th anniversary. He's on vacation until after DefCon (maybe he's going?), but I was told that he is answering his email. I've sent off a message inquiring about the missing schematic page. As soon as I know more, I'll let you know.

The public relations person I spoke to also mentioned that they had to hit eBay for some of the necessary components. Should we get the schematic and re-create it, I'd like to find out if they are still missing anything and send it along to them if we have it.

[LosT]

Re: 50th Anniversary of "Tennis for Two"

Please follow up on this. I would be interested in building it. At the very least I could design a replacement, but it wouldn't be the same as recreating the original.

Thorn, you can still show this year you know :)


LosT