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DigiBarn Stories:
The Restoration of the LINC
Script of the Restoration Team



Selected (edited) correspondance from the LINC restoration saga (2006-2007)
(All photos credit Gerald Johns unless otherwise noted)

The following is an edited transcript of the communications between the various members of the LINC restoration team members. The cast includes:

St. Louis team: Tom Chaney, Gerald Johns, Scott Robinson, Jerry Cox

Bay Area Team: Severo Ornstein, Bruce Damer

Distributed team: Wes Clark

Other supporters: Gordon Bell

Threaded communications in reverse chronological order

Initial Communications with the St. Louis and distributed LINC teams from Bruce Damer, Digibarn Curator (14 September 2006)

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LINC parts in storage in St. Louis

Hello Severo, Gerald, Scott and everyone, Bruce Damer of the DigiBarn here. Thanks for initiating all this. My goal in being a part of this would be to help bring to general consciousness the fact that the LINC is perhaps the first true "personal" (or at least portable) computer and get it more widely publicized. Every year we do an anniversary event here in the SF Bay Area and the LINC would be an admirable subject for next year (this year it is "Apple in the Garage" with Steve Wozniak et al).

If this was all successful I would work hard here and find a way to arrange shipping from St. Louis (something always comes up, we managed to move two Cray supercomputers and a whole network of Xerox machines in years past). So if any restoration effort goes ahead you have my full (if remote) support and if any video or photos or text (Blog, reports) of the restoration were produced I would feature them on the DigiBarn site.

I wish I had the technical skills to help but I can at least help to bring this to the attention of the computing history world. All the best and thanks again for considering taking this on! LINC-on!

Bruce

Initial technical concerns and some fun stories from Tom Chaney (14 September 2006)

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LINC tape drives

The Caps may be bad, but they can be replaced. Perhaps with a new capacitor about ½ the size of the original, but they can be replaced. Note I’m not playing strict Historian here, but these parts are inside and will not be seen. With the documents Scott Has, there should be no problem figuring out what each capacitor has to do, and testing or replacing the Caps as needed. Finding some working link tapes may be a bigger issue. I guess we could toggle in a program That just moved to a tape block with a non-working tape mounted. Not very satisfying.

Bruce, when Scott was in early grade school, I would take him with me to work on Sat. He had his own Link Tape, and would pull a stool up to a Link, start up a machine and play games. The Link Made a great “baby sitter”. Toward the end of the Link era, my Scott had a working Link In his bedroom. By then, these “Apple” things were appearing and they had more appeal than a Classic Link, so he never did much with his first personal computer. One last story. Just after we set up the machine in his bedroom, Scott got in trouble at school and had to write sentences. He wrote a program and had the Computer print out the sentences. It ran a bunch of pages. I think the printer ( a modified selectric Typewriter) printed for a half hour. I remember it printed for a L-O-N-G time. I was so sure the teacher would be upset and throw the whole thing out that I let Scott do it. The teacher was so surprised to get the printed pages that he let the kid get away with it!

And again later from Tom Chaney...

I really used Link? Wow! It took me years to use the word “link”. I used “linc” in everything I wrote for a very long time. I was always fixing the spelling while proofing. Scott has 4 machines, which he claims all worked when he took them. One of the machines is the BCL tape formatting machine. So if we can at least get blank tapes That still have the iron oxide stuck to the tape, maybe we can re-build some stuff. . . . or better Yet, maybe we will find some good tapes.

O-yes, in addition to the four machines, Scott has a fairly large collection of DEC modules, including extra memories. So If the “second” machine is just for parts, we may Be able to fill that need in a different way. O-yes, one of the machines Scott R. has IS the one Scott C. had in his bedroom. I forgot to tell Scott last night that this building is ramp equipped. His getting in and out here should not be a problem. Transistors typically don’t age. With four sets of stuff to work with, getting at least three working Power systems should not be hard. But if we DO need to buy replacement transistors, then yes, There is a problem here, or at least an interesting engineering job slowing down today’s parts to Work in yesterday’s systems.

Tom

From Gordon Bell (15 October 2006)

I think we'd all like to see the LINC in operation. Having two of them would be great.

The LINC really is the first PC as we know it.

From Dick Clayton (16 October 2006)

I surely support the idea of an operational LINC. It was the first practical integrated Lab System and a real "personal computer". All the components except possibly the power supply and tape drive are full of standard parts. Having one or two backup's would assure a good spares. The only other problems I could imagine are with the connectors, they are gold plated and have a limited number of insertions to their life. This probably wouldn't be a problem in a low vibration situation without high humidity. I would be happy to help or even lead such a venture if it became a project. I even saw the production tech for the LINC system @ DEC, (Jim Scanlon) last fall in Boston!

Regards, Dick Clayton

From Tom Chaney to "The Management" (25 January 2007)

Dear Management, There has been some progress. Three of us gathered at Scott's house earlier this week to have a look at things. As are result of this "look", a meeting of the people (if not the minds) is set for this Sat. at 1:30pm (CST) to move two LINCs from Scott's home to the STS office space. Gerald, (yes even, Gerald) upon seeing the state Scott has kept the LINCs all these years was heard to say that these LINCs just m-i-g-h-t turn on and run. We will see. Scott needs to be recognized in some special way when this is all done and in place. The "people" meeting this Sat. include Scott (of course), Gerald, with his pickup, me with my Scott's Jeep, and maybe his trailer, and Jerry with his grandson in law (Troy) and his pickup and trailer and two wheel dolly. The move should happen in one trip. I trust that this report of the actions of the St. Louis contingent will at least change the color and texture of our "Mark" from a bright black to at least a dull gray.

Tom

Men at Work! Moving the LINCs (and parts etc)

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From Gerald Johns on the successful move of the LINCs (27 January 2007)

Severo:
A group of us met at Scott Robinson's house today and we moved two sets of LINC computer components, some documentation, a fairly large inventory of DEC System Modules, and none of Scott's cats to the Chaney STS company. There are pictures and they show just how bulky and heavy computers were in the 1960s. I will try to get up to STS about midweek to start the assembly and test phase. We chose one of the original machines, and one of the ones assembled later out of 'spare' parts. I think I will choose the later machine as the first example since it is less worn.

gerald

From Wes Clark later that day

WAY TO GO! AND KEEP THEM PICTURES A'COMMING!! -- Wes

From Severo Ornstein also later that day

Eureka! Way to go, guys!! Thanks to everyone who helped with the move. I look forward to any pictures and to news of further developments. Wish I were there to help (and smell the burning resistors) - WHO said that? Onward and upward!!

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Working on the LINC at STS

Restoration Report from Tom Chaney (19 February 2007)

Hello, Gerald worked at least a solid day on the LINC last week and made some progress. The console is mostly working now, and the next thing was to store a few word program in the memory so we could test the display. The memory doesn't work. Gerald thinks it's the -3V supply. I have spent some time looking at the -3V, but haven't figured it out yet. Among other things, the -3V supply counts on it's load to work. At no load, the "-3V" supply puts out zero volts. So I tried to measure the -3V with the LINC running and everything hooked up. The documentation doesn't seem to agree with the memory driver board, so I'm not sure which connector pin should have -3V. Hard to debug when you don't even know which pin to look at! I've been doing a different puzzle (a PC board layout). I'm getting a little tired of my board layout puzzle, so I'll take a break this afternoon and puzzle over the LINC a bit more. Wes, I have the LED stage light driver/dimmer circuit mostly working. I ordered a different pot. Fri that will adjust the maximum current delivered to the lamps. This pot will function as a "color adjust" control. I have another pot that adjusts the lamp on time per cycle, and thus the lamp intensity All this works fine now. The really-really dim to lamps full off transition as you turn the pot is now nice and smooth. There is also a toggle switch that turns the lights on and off. So any intensity can be set, then the lights turned off. When the lights are turned back on, they will go to the set intensity When the lamps are switched on, the light level rises to the pre-set light level smoothly over a 1 to 3 second interval. Looks just like real stage lights coming up after in intermission.

Back to the LINC, anyone have any handles for DO-TOG, etc. switches? They are black, about 1/4 inch in diameter, about 3/4 inch long, tapered at one end, and have a threaded hole in tapered end so the handle can screw onto a #6-40 threaded stud that sticks out of the switch. We have two switch handles, we need three per machine. I plan to buy a #6-40 tap and make a handle, but thought I would ask in case there was one about. The story goes that the handles were removed for the LINCs so the switches didn't get broken off in storage, and that all the handles were put in a common bag. That bag has not been found. Scott found two spare switches, complete with handles. That's were the two we have came from. NOTE: "normal" #6 machine screws have 32 threads per inch. The 40 threads per inch is not very common. One hardware store told me the sewing machine industry used the 6-40 screw system. Clearly not a big rush to get the switch handles fixed up. The switches work by pushing on the little threaded stud sticking out of the switch. It takes some pressure though, and one's finger gets a bit sore if the switches are used a lot.

And just four days later on 23 February, 2007 from Tom Chaney...

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From the title you can guess at what comes next.

As you will recall for the last message, the LINC memory was not working. Investigation had shown that the -3V supply was not working. Gerald remembered, or had worked out, that the -3V supply was mostly used by the core memory circuits. The -3V supply line measured about -0.24V. I started testing the -3V supply. The design of the -3V supply is such that it only works if there is a load on the supply. (the load goes between the -3 and -18V supplies, NOT from -3V to ground.) I placed a dummy load on the supply output, and the -3V supply worked fine! (note: I skipped over a few hours of finding where the -3V and -18V connections were in this discussion, but let us continue.)

So yesterday morning, armed with the information of what the load needed to be to make the -3V supply work, we turned to the schematics, located a bunch of resistors that could be switched so that they are connected from -3V to -18V if the logic worked out just so, got out a spare memory and measured the resistors (the schematics skipped over labeling this set of resistors with their value!), did a bit of math, and by George, if all (or most) of these resistors were connected between -3V and -18V, then the total current draw would be about right to cause the -3v supply to operate correctly! So next we turned to finding the one logic signal that could cause the resistor switches to be off. In the process, we found that the resistor drivers were fed from the memory address bus in a way that only worked if all but one of the resistors were connected. The one resistor not switched on was then the Core drive line bit being addressed. So, this told us that the whole memory address bus had to be hosed to turn off all the resistor drivers at once. There were no control signals needed to be pulsed, all that was needed was the address bus ON, didn't even have to be working, just ON.

AND THEN A Light Begin To Turn On. . . . . .

You know, it's not like we had never pushed on the memory unit to make sure it was seated. We had. Several times. We had wiggled and pushed, and the memory unit just sat there. But yesterday, we pushed and shoved some more. We even removed the fan that spans both memory boxes so we could wiggle and push on just one box at a time. We were doing all this while testing the memory at the console. After we removed the fan, we got one bank of the memory to work for a little while! So now we pushed and shoved with earnest, but only got intermittent operation. So I went home and collected a 5 ft long two by four, and some smaller wood blocks, AND an 8 lb. sledge hammer. We had used it all, including the sledge hammer, by the time we got reliable memory operation. Those memory boxes ARE fully installed now! (O-yes, and the -3V supply is now measuring -3V.)

Anyway, with the memory working, Gerald drew a line on the 'scope, and was able to move the line up and down with a knob. The delay works. With it set way down, you could see the line being drawn with a series of dots. The display box and it's knobs seem to be, at least mostly, working. We didn't test every knob or do anything complex on the 'scope screen. But it was good to all that do something that seemed about right.

So, THAT was most of yesterday. We did move on a little to the next problem. There appears that only part of the Reset circuit is working. I replaced the DO-TOG / STOP switch. There is a note about bending the STOP switch contacts so that one set of contacts close before the other. I need to check that I have that correct. Gerald is planning on being here next Tue., and we have this (probably way over optimistic) hope of having some tape drive action by the end of that day.

And on the 24th Tom Chaney writes on working up to the eight pound hammer!.

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Boxes of LINC modules

There’s a lot of Charlie in me. He always insisted on working and re-working material before it was published. He drove the rest of us nuts! There is even a LINC document that was never released. We have located a boot leg copy of that document here in town. This document covers the LINC tape drive theory of operation.

So where am I going here? I see some value in these stories. This is what really happens and how a “single point of failure” turned out to be that some 220 contacts were not made. Not the first place to look. I was thinking early this morning of how to expand this little story and your note got me going again. I took some pictures of a memory unit out of the LINC, and also a single card. A single CARD in the LINC has 22 pins, and is hard to get in and out. I don’t think one of the cards can just be pushed in. One has to wiggle up and down while pushing HARD to get the single card in. The memory unit has 10 rows of the same type connector, so a memory unit is 10 times as hard to plug in as a single card! I just removed a single card from the “spare” LINC and tried to plug it back in. I then tried to push an equal amount on a bathroom scale held on a wall at about the same height as the card I was pushing on to get some idea as to how hard I was pushing on the card. The bathroom scale read a little over 30 pounds, and I STILL had to wiggle the single card. So the memory unit takes over 300 lbs of push to get it in, IF you can push that hard and also wiggle up and down! When that much force is applied, it’s really hard to wiggle also. So I think this means that any real memory insertion scheme has to push quite a bit harder than 300 lbs.

This is how we slowly work our way up to the 8 lb hammer! In fact, the 8 lb hammer banging on a block of wood held against the back of the memory box didn’t do it. I had to set the two by four board in place, acting as about a 3:1 mechanical advantage lever, and then bang on the end of the two by four, WHILE holding static force on the lever as I was banging. ( I was rocked back, with my weight hanging on the two by four near the end, but with my fingers back enough I could swing the hammer and hit the end of the two by four - - got the picture?) AND then I had to set the butt end of the two by four near the bottom of the back surface of the memory box, then toward the top end of the back surface, back and forth, to get the whole memory box to wiggle up and down as I was trying to drive the memory box forward.

Severo’s right, we do need to get this on video.

Tom

And also on the 24th Severo Ornstein's note about Tom Chaney's historial role as "Mr. Glitch", interesting background on this member of the restoration team (24 February 2007)!

Back when we started working on Macromodules (self timing logic) we first realized that all the synchronizers the world had been using were vulnerable because many assumed that flip flops would settle when hit by ambiguous signals within their usual turnover time. Tom is the person who demonstrated that that's not always true - that in fact in theory they could hang up for arbitrary lengths of time. To do this he had to create the ambiguous signals resulting from timing conflicts (e.g. one side of a gate opening up just as the other side shuts down) with very tight tolerances. He built special equipment to allow him to study these cases (vary timing very tightly) and was able to photograph the results demonstrating the problem. A whole generation of digital engineers had grown up believing that everything, including timing, was completely digital and, believe it or not, serious engineers (even at the holy MIT) debated whether glitches actually could occur. Tom became Mr. Glitch for a while.

As you can tell, he's a fine engineer with Charlie's sense of carefulness and attention to detail - despite the sledge!

Back to it with Gerald Johns (27 February 2007)

There was not much progress today, but some in the negative direction. I have not lost my inverse Midas touch!

This morning, the tape transport 1 seemed to be almost ready to work. I could exercise the RDE, CHK, and MTB instructions, and the tape sometimes would emit the characteristic chirp and compute a valid checksum. Reasonable-looking data appeared in memory after the read operation. Since transport 1 seemed better than transport 0, Tom soldered up a unit-interchange plug and onward we went. As the day progressed, the reliability of the tape went from marginal to incompetant. At the end, I could not even keep the tape moving with the motion bit on in the tape instructions. I brought home a reduced-size copy of Vol 12 in order to study the logic diagrams. On Thursday, I may do some swapping of the reader-writer cards, and I plan to try to follow the tape data to see if the mark, timing, and data channels are doing reasonable things. Of course, I have to have enough cooperation from the tape that it will keep moving when asked.

gerald

And at Long Last on May 16th, 2007 Tom Chaney writes (photos taken 14 May 2007 despite the date on the screen):

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Display in the Light reads:
(photo credit Tom Chaney)
1 HELLO
2 THIS DISPLAY
3 FROM LAP6
5 MAY 13 2007

OK, so there are two pictures. * Not all that works, works all the time (A warm machine seems to be a happier machine.) *

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Operational Front Panel
(photo credit Tom Chaney)

Not all works at all yet * BUT I D-o-o-o-o CALL THIS PROGRESS!!!!

Tom

From Wes Clark (18 May 2007):

Tom: GREAT NEWS! ! Clear proof that the PhoenixLINC is indeed coming back to life! I assume that Gerald is thrilled a bit too. -- Wes

From Tom Chaney (21 May 2007):

Bruce, I don’t think it’s quite time to schedule a truck. The tape system is still very fickle. Getting to a more solid state may be quick, and it may not. The notion of getting the LINC to California enough in advance of the “event” so there is time to fix what ever stops working during the travel is a very good idea though. Several, maybe “most”, of the fixes turned out to be just a mechanical adjustments. Replace bearings and belts in the tape drive, twist some potentiometers to adjust the power supply voltages in the display ‘scope power supply circuits., fully plug in the memory, etc. There is the one capacitor that had to be replaced to get the chime working, and Gerald has done some board swapping with the second machine at STS. (I view the second machine as slowly getting deader and deader as we work to get the first machine fully functional.) So there has been some electrical changes. November is now 5 plus months away. The LINC moved to the STS space on Jan. 27, a little less than 4 months ago now.

Things to do: (with no input from Gerald, so this list is, by definition, is incomplete.)

(1) get the tape drives working well enough that LAP 6 can be loaded from tape unit 0 at least 80% of the time. (Right now, we have to use tape unit 1, and we can get LAP 6 loaded maybe 30% of the time.)

(2) We need to try to write a tape. So far, we have only read tapes.

(3) Clean up the machine. The latches on some of the door panels are bent up and will have to be repaired or replaced. There is a fair amount of just scrubbing of panels that needs to be done, and some of the plywood is de-laminating. So there is a bit of gluing that needs to happen.

(4) The display is a bit dim. It would be nice to get the display a bit brighter. There are a pair of Ne lamps that adjust the bias voltage on the intensify grid of the CRT. These lamps probably need to be replaced. Both Gerald and I remember there is some sort of wear out phenomena associated with using Ne lamps in this sort of circuit. The catch is that these two Ne lamps “float” at about -3000 volts DC, so one doesn’t just grab the ‘old lab VOM and jam the test leads into the circuit to take direct measurements.

Maybe the best thing that has happened here at STS is that we are learning where to look first to fix problems. If the trip West does brake the machine, we may be able to “fix” it a second time there a lot faster.

From Tom Chaney (22 May 2007) on Restoring a Second LINC (and keeping either of them working):

I talked to Gerald about doing a second machine for St. Louis, and he is interested. We can fix anything in the display except the CRT itself. That's a special with long persistence phosphor. We can probably get a second display going, I just need to spend some time with the other displays. Depending on the discussion below and my descending list, we should probably send two working displays to Calf., so we need three of the four working to cover all spots.

Getting a LINC working, and KEEPING it working are different. And if we don't KEEP the LINC working, why bother? The life time of the tape drives is probably 10 to 15 years. Less if the motors don't turn from time to time. The drive belts takes a set, so the tape doesn't run smoothly. All the belts I removed from the drives were junk. The bearings also need to spin to keep the balls coated or even the ball bearings die. I had to oil all the other fans in the LINC to get much air flow going. The circuit breakers in the power supply are also a problem. They are silver contacts. The power contacts are more tolerant, but the circuit breakers each have an aux. contact that is used as a logic function. All the aux. contacts are connected in series so that if any one breaker trips, the whole power supply is shut down. The two power supplies we moved to STS arrived differently in that one of the supplies had all the breakers in the OFF position, and the other arrived with all the breakers in the ON position. The power supply with the breakers in the ON position (contacts closed) is the one with the working aux. contacts. The power supply that sat all those years with the aux. contacts open and exposed to the atmosphere will not turn on. It's possible to clean the aux. contacts, so we could probably get the aux. contacts working again, but it's another thing that keeps the LINC from remaining working in a museum setting. I had to "wiggle" several pots. also to "fix" some things.

So we need to think about why we want to put a LINC in a museum.

Here's my view of what's impotent, in descending order if importance

(1) The physical structure is probably the big thing. Perhaps with open doors, perhaps with a logic module card or two laying nearby. Perhaps a core memory unit, Probably with several signs showing parts. Even if we had a fully functioning LINC, the machine would spend almost all of its time in this state. I don't see there being a regular schedule where the machine is turned on, even once a week for an hour or so. The museum would have to keep someone on staff trained to do the hour per week. After a year or two, I'm guessing this would fall by the wayside, even if it started. But on with my list, the next most important item:

(2) If the machine would turn on and console lights light, that would be a plus. Just seeing this, with signs explaining things, or a speaker, I expect would be as much as most in any audience would grasp.

(3) If the clear memory button worked, and the step fill / step examine toggle switch worked, we could see patterns in the lights. That would be cool. A few folks would get this.

(4) ringing the chime, and hearing the speaker connected to an acc. Bit line is interesting. I think the idea that you can "hear" your program run is a good one to get across. One could change the clock rate, or add a no-op to the program, to show that the sound changes.

(5) If the tape unit would move a tape just using the buttons on the tape drive. Again, this shows all that is visible. Starting the tape from a "do-tog" looks just like running the tape for the tape drive panel.

(6) If the display could display a line. (load program through the console switches, use XOE STOP to run the machine clock slow so can see display dot details.)

(7) If the tape unit could move a tape, even just toward a block, using the "do-tog" toggle switch, even if the operator had to stop the tape because the block didn't read.

(8) if the display could display some text. Seeing the display do both graphics AND text seems like something folks would remember. I don't think folks immediately make the connection that text is just a special case of graphics. Also speed is important here, It's nice show how much text can be put on the screen.

(9) if the LINC had a functioning tape drive.

(10) if we could hang a sign stating "this a working computer"

(11) if we could arrange regular live demos, once a week say, with someone in attendance who could answer questions, load up some programs, play a little tic-tac-toe, run the DRAW program, etc. This level of working with the LINC could keep things alive and well for a long time.

(12) if on special occasions, one could sit at the LINC, load up LAP 6, and enter a simple program and then run the program.

Just doing (1), the LINC can last a long time.

Right now, the LINC we are working on can do (1) through (7), and about 30% of the time, we can do (8). And we could probably get a second LINC working up to (7) without a huge amount of work.

If the first machine we are working on just sits in a display, how long will it be able to do (2) through (7)? Probably a year to a few years. I don't see it still working in 10 years.

Also, note I have said nothing about appearances. This would be part of (1), so perhaps we should be working harder on cleaning and repairing the console/display/tape boxes. The plywood is de-laminating and needs some glue. We could even think about fresh paint. We have the PMS number of the paint. Also the panel cover latches need some attention. Some are all bent up. And there are the signs. I expect we are the group that have to come up with the words for the signs.

So enough from me. I would like to hear some of your thoughts.

Tom

And Tom Chaney again, on negative LINC restoration progress, but just for a short time (29 May 2007):

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LINC tape drive

OK, things are back on track, maybe a little ahead. All in all, its been a reasonably good day! Skipping over the wild goose chases. (But which resulted in some really nicely polished main power line contactor contacts along the way!) The problem was the elapsed time meter! At 9633.8 hours, it choose to die, making some really horrible sounds. The meter is mounted in the middle of a 16 by 19 inch panel and was apparently resonating with the natural frequency of the panel thus making lots of noise. It's now disconnected.

I got the elapsed time meter disconnected, turned the LINC back on, and tape unit 0 would not stop spinning! So maybe the power supply problems were bigger than I thought. After checking power supply voltages and wondering if I had REALLY fixed the power supply, I ended up re-seating the relays inside the tape drive console, and banging on them a bit. (soft bangs you understand) This fixed the unit 0 motors running. Upon playing with the button switches that make the tape drives run, it looked like the tape drive 0 motors were now acting more like tape drive 1, so I called Gerald, who gave me the switch settings, and loaded up LAP6 from tape drive 0 with no re-tries of the tape motion! It just read LAP6 in and ran! I've had the LAP6 running for almost an hour now with no problems.

So it looks like we are close to having a working LINC. Although, we may continue to have set backs as things start failing. We'll just have to wait and see how things hang together. And Gerald has some more tests he wants to try. He's even beginning to think marking a tape!

P.S. I just checked the LINC, still running. I even stopped and resumed the program a few times, it all works.

Tom

And Wes Clark responded:

Fantastically good news!! Full marks for perseverance & fortitude!!!

Gerald Johns writes a dash of cold water (14 June 2007):

Severo:
Last week, the one sort-of working LINC was in good enough shape that I was able to run LAP6 on tape drive one, edit, convert, and run a new program and view the results. Since that was so wonderful, I tried to improve the performance of tape unit zero. I managed to disable the tape subsystem completely. Tom has been very busy with STS business, so we will visit the mess together on Tuesday.

Tom and I both think that one LINC can be made to work just well enough to do a video (with some judicious editing), but there is no reasonable hope that one of the old machines would continue working as a museum exhibit. Jerry has expressed the desire to bring a second machine back to enough life to at least flash the lights in St. Louis. I think that with the four LINC machines that Scott preserved, we might be able to make the historical video, and get one to power up and look a little alive. We would not want to spread the parts over a wide geographic area, so don't send the truck just yet. Let us all talk, maybe after Tom and I can try to undo my last improvement to the tapes.

Little changes, the inverse Midas touch is still in control. Gerald

Pictorial selection of LINC hardware and internals

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LINC parts in storage in St. Louis
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Project Upate

August 5, 2007 - and now we are planning on the finalization of the restoration there and planning for the move to the Bay Area of Northern California sometime in the Fall of 2007. Watch for the special event with the LINC(s) and members of the LINC and restoration crew at the 10th Annual Vintage Computer Festival (Nov 3-4th, 2007) at the Computer History Museum.


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