I Bought the HEAVIEST Computer on eBay: The PDP-11/34!

[@Remowylliams]

It's scary to remember so many operational facts about these computers. In the early 80's I got hired by a 3rd party DEC service provider as a bench technician fixing VT-100 terminals. After fixing all the broken terminals on hand. I turned to work on our 11/40 test bench machine which had been down for nearly a year prior to my arrival. I taught myself how to repair and operate the machine and in 9 months became the company's senior field technician. As long as I had test equipment, schematics and coffee I fixed most everything I was thrown at. Floppy Drives, Hard Drives, Tape Drives, serial controllers, line printers, power supplies. These machines had modular switching power supplies that would fail pretty frequently. I built electronic dummy loads that dissipated power through 2N3055's strapped to massive heatsinks with fans blowing on them. It was a great time working with these work horses. Thanks for the memories. I'll watch any PDP-11 video you put up. Cheers.

[@spvillano]

2N3055 brings back some memories. Thankfully, the burns healed. ;) Used to watch an FNG come in and screwdriver discharge filter cap banks, welding the screwdriver to the bus strip. Hey, we told him to check with us first before doing anything exciting or energetic! Haven't worked on that kind of logic in ages. Now, it's all pretty much PC, NUC, RPi, Deep Thought... Nobody trusts me to do any work on Earth.

[@wizardpb]

In Sept 1978 I started a PhD - the day I started, my supervisor showed me into a newly constructed computer room, false floor and all, and showed me a brand new PDP 11/34. He handed me a 9-track tape, and a single piece of paper. He said: "This is Unix Version 6 - please get it running on this machine". On the piece of paper: the tape deck bootstrap, all in octal.... 46 years later, I'm now retired. Ah. memories....

[@SaraMorgan-ym6ue]

meh seems kind of small to me he got ripped off🤣🤣

[@josephgaviota]

100032/ / / Ah, the good old days ;-)

[@daphnepk]

At least he gave you it in octal rather than just assembly and letting you work out how to encode the instructions yourself …

[@gauravverma5692]

Whats your PhD in?

[@postiemania]

50 year old Computer and there is an expert on the net to help you fix it.....amazing.

[@DC9V]

The fact that there were several people betting on that thing already left me stunned. 🤷‍♂️

[@postiemania]

@@DC9V I had no doubt that Dave would not stop until he had it working.

[@Verminator151029]

​@@postiemaniaI can only imagine it's due to his ASD!! Guess that's a good thing.

[@vinguarinovg]

Yes, some of us are still alive and even still working! ;-)

[@ethandicks3]

Lots of us who used these machines in the 70s and 80s are still around.

[@waslucena]

In the 2000s, the Rio de Janeiro metro was still running on PDP-11 systems. There were five PDP-11s for ticketing and four for the automatic pilot system. In ticketing, one PDP-11 acted as a supervisor, selecting which of the two controllers for the turnstiles would be the master and which would be the slave. The other two PDP-11s, along with four tape units, recorded the data from each ticket passage. Each PDP-11s had 96K words of memory. Motorola developed a specific serial communication chip to connect the central system to each entry turnstile, as the distance was over 30 km/18 mi. The PDP-11s for the automatic pilot system allowed for acceleration and braking at stations without human interference. Access at the turnstiles was through magnetic stripe cards. The turnstile would read the card and send the data to the PDP-11s, where the cards were validated. If they were multi-trip cards, one trip would be deducted. If the card's trip credit was exhausted, the PDP would instruct the turnstile to retain the card. Otherwise, the PDP would send a command to rewrite the card with the trip deducted. The project was developed by the French company Alstom in the 1970s, and the metro was inaugurated in 1979. It's incredible to think that all this was still running in 2000, and the cost of a technological upgrade involving the replacement of all the turnstiles and PDPs was not deemed worthwhile.

[@systemic_disclosure766]

What would you say is the difference in the power consumption to these old beasts vs modern computers?

[@waslucena]

@@systemic_disclosure766 Replacing the PDP would mean changing all the turnstiles and the entire communication system, decentralizing operations at each station. This would require replacing the entire turnstile control system, carrying out construction work at the stations, and so on. Therefore, the total cost wasn't feasible at that time.

Washington, will you allow us to translate your response into Portuguese and publish it on Retrópolis? (With a mention, of course.)

[@rya3190]

​@@waslucenaWhile probably not ideal, you could run a Microcontroller/computer with a decoder at each turn style (area) and connect them together on the old main line for a central controller. In 90, this probably would've cost 2 or 3000 (not including labor). But yeah, seeing as they probably had experts on hand, as well as spare parts, for repairs, and it being a known quality (well tested), it makes since to wait till the metro needs remodeling.

[@someguy4915]

@@systemic_disclosure766 Depends on how much the PDP-11s consume but an RP2040, STM32 or similar could run all of that in the milli-amp range, the real power consumer would be the transceivers to connect over 30KM length cables, still in the single digit watts though.

[@mushroomsamba82]

When you need an engine hoist to move your computer you know you've made it.

[@antitunnelvizie5877]

Thank God for that ;) btw Nice Poket calculator

[@noth606]

How about when an engine hoist is far to small to lift it or move it? I once had a VAX 11/750, brought it up to the third floor to my apartment, only to misassemble it by connecting the PSU main fan airflow sensor to the wrong port blowing the thing. By brought up I mean I disassembled the whole thing and brought it up piece by piece using the stairs, I had no elevator. But about the same time I also got a PDP 11/23 which worked a treat. The VAX ended up at the dump because of the airflow sensor, there would have been a way to cheat it and get the main stage of the PSU to power on, but it was far beyond the means of a 16-17yo me. I lived alone at the time and had about $40 a month to live on, which was enough for fast cook macaroni and ketchup, and some ramen in the weekend if I had been frugal. Still feel bad about the VAX going to the dump, but that's where it was headed before I tried to save it and failed.

[@naikrovek]

If mainframes weren't vendor-locked, I would have a few by now.

[@markteague8889]

Or lost it ... ROTFL :P

[@noth606]

@@naikrovek what do you mean by 'mainframes'? Also, most systems are not really vendor locked, so not sure what you mean there. Some software is hard or impossible to get as a private person but most of that doesn't stop you from running them, just stops what you can use them for. Like some compilers are nogo, some specific functions on for example large IBM systems like LPAR require feature unlocks by the vendor, meaning if it's not unlocked when you get it, you won't be using it, and if it is unlocked it won't be if you upgrade or reinstall the OS in certain ways. Most of those things you can work around if you know what you're doing, without help from the support. Or - ehm - official support at any rate, it helps if you are not totally some unknown guy 'off the street' to them.

[@ethandicks3]

Glad I've been able to help. The PDP-11 is a fantastic machine and it's great to see (another) one come back to life.

[@wa4aos]

PLEASE more DEC ANYTHING. I was with DEC for years from PDP 8 series through most of the VAX series. I know these systems frail to most simple systems now in some ways but the evolution of DEC over the years was amazing. I am happy and honored to have been part of the excitement. In case you may be interested Ken Olsen did everything to keep the payroll running even when times were tough and we did have some lean times. He made some errors in judgement by not getting in the PC biz earlier but there were no crystal balls then and as they say, it is what is or was, as the case may be. Thanks for keeping some of the DEC gear going and preserving the tech on your super neat YouyTube channel !!!

[@vinguarinovg]

Yes, more DEC! Another ex-DECcie....XXDP+ was my OS! Worked in Comm Diags.

[@vmisev]

Hear, hear!

[@timradde4328]

I feel that DEC trying to get into the PC game was one of their poorer moves. This is not the venue that DEC was great at. Too many companies tried and most failed at the PC market. I worked at Sperry and they made one. Never really went anywhere but it seems they thought they had to try. I wanted to work at DEC but they never contacted me for an interview till I was already at Sperry for several months. I am a big DEC fan. I learned computers on the pdp-8i running TSS/8. Later got into the pdp-11 line and then then pdp-10 (KA-10). I have the pidp versions of each that Oscar sells. They are miniatures of each but with the same but smaller front panels and switches. I have one big pdp-11 left.

[@edasm4113]

Greatest design and most clever and consistent architecture between generations. Learn it once and you've learned it forever,

[@axelBr1]

I wanted to work for DEC after seeing a VAX 11/780 at the lab my father ran, but ending up taking a different engineering subject. But did end up using microVAX IIs and Alphas during the 1990s. I'm wasn't a systems engineer but was able to do some pretty cool things with the cluster, the ease at that it was possible to log onto one computer and then run an application on another computer, using the hard disk from another I still find amazing. We did have DEC PCs, but I doubt they would have saved DEC. I've heard that Ken Olsen was a decent guy, again marking out DEC from Bill Gates and Microsoft who haven't innovated a single thing and every product is stolen or cheated from somebody else.

[@jaimeduncan6167]

The fact that one can run a full PDP-11 emulation on a Raspberry pi is such a flex of the microelectronics and computer industry (the software that allows to laying billions of transistors and perform optimization of the wire layers). Congratulations on your new BB

[@dmacpher]

Sort by “heaviest” is really an under appreciated feature

[@tripplefives1402]

Too bad dating websites lack that feature.

[@k_a_bizzle]

@@tripplefives1402*rimshot*

[@MK-of7qw]

more bounce to the ounce, kids!

[@float32]

FLOPS? No no, LBS is what makes the CPU go brrrr.

[@madyogi6164]

Mom, I just bought my new "PC". Just leave the garage door open and move the car...

[@bobbyb7635]

PDP 11 best system ever made. All us dec folks appreciate you getting it running.

[@bongolian3101]

I really enjoy the way you narrate. You're refreshingly emotionally neutral, concise and comprehensive. Thank you for a great and informative video!

[@DavesGarage]

You're very welcome!

[@MarvinWestmaas]

.. would the emotionally neutral narration have something to do with being on the spectrum? I for one enjoy it as well, it's well suited to run a channel like this ( or a teacher.. though there it's hit and miss if your students appreciate the bare bone business approach or if they want their fragile egos touched lightly and with 'consideration' ). ps I'm on the spectrum so are both my kids so nothing negative meant ;)

[@richardclarke376]

His delivery reminds me of Clive James. (That's a good thing btw)

[@tr3vk4m]

@@MarvinWestmaas This is not a ZX Spectrum - it's a PDP-11

[@MarvinWestmaas]

@@tr3vk4m I think I am missing the point...

[@randygreene5977]

My first home computer was an 11/70 that was given to me if I would haul it off. Never got it working. Gave it to the local college and they were in heaven. They got it working and off they went running Unix on it. I got some free education out of it that helped my a lot over the next 40 years.

[@EngineMisfire]

I was a coop student in the late seventies, working for the DEC manufacturing facilities in Puerto Rico. Our factory used to create PCBs from scratch, many for all the series of DEC PDP computers ever made. On my first day at the job, they gave me a Simpson meter and had me look for shorts and opens on many of the boards they manufactured. I worked with some of the smartest engineers at the time. If you look and find circular stamps with the letters SG or AG, the board was made in Puerto Rico. At one time, they began work on PCBs for the VAX line of computers. One computer that never saw the light of the day was the PDP 11/77. It was a dual-processor version of the PDP 11/70. However, it was canceled because it was too fast compared to the PDP 11/70. This was one of the best jobs in my EE career. 173000G!

[@RallyCarDelta]

My previous employer, at one point, had multiple PDP-11 stacks in our server room. By the time I was brought on board in 2006, the environment was emulated, but the machines were still there. I had a chance to look them over multiple times before they were eventually fully de-comm'd. I learned a lot about the environment because of the emulated stack (a few of our manufacturing systems required a PDP-11 "backend"). I've heard hundreds of stories about these things, from people programming them, to troubleshooting the smallest of software glitches. (Who dropped the cards??!!) Eventually, in 2020 (during COVID) we removed the legacy system at the one remaining plant that needed the emulated environment to operate. I gained a ton of respect for these machines in the process. That "system" (even if emulated) carried us through all the way to 2020.

[@mikeeru]

Interesting to know that emulation of PDP-11 was created and used not only for nostalgic / fun purposes!

[@kerryedavis]

Too bad you didn't grab a few when they were "let go." A lot of that stuff wound up just being scrapped.

[@hessex1899]

When I was in college the PDP-11/45 that we got out of the trash at Bell Labs (I realize this is a lot to unpack, also we totally didn't Redbox the call to Bell Labs to arrange for the pickup) we disassembled everything and moved it all piece by piece. This was much easier, it also helped to have a house full of college students. I am really happy that you got a big PDP. It brings back memories for me. We ran RT-11 on ours.

[@SpeZi-tr6gr]

Vintage computer and a muscle car in the garage. Guy's livin' my dream. Well done sir, well done!

[@TheWiedemS]

We need a video about his cars!

[@morganskinner3863]

I first used a PDP-11 in college at 17 ish, that would have been 1984. I wrote a Z80 emulator on it for my final year project (I was a confirmed Sinclair fanatic). There was a much larger PDP-11 (70 I think) at Polytechnic, and then I moved on to VAX’es when I started work in 1989. They were superb machines, and I fondly remember them. Manuals! Real, proper manuals that told you everything. Being a true geek I learned VAX Macro assembler and wrote a modem driver in it - this was used to communicate between remote sites in the UK. I think my finest hour was patching an RMS database that was corrupt for a water company in Eastbourne. All in all, I loved it. And I retire today! Now it’s pet projects that will keep me busy, I can’t wait! Thanks for the content Dave, you never cease to be inspiring and interesting.

[@jyvben1520]

Z80 emulator, does it run on a rpi pico ? so you could run a sinclair game/program on a pdp11?

[@morganskinner3863]

@@jyvben1520 - not a chance, plus this code went to the great bit bucket in the sky around 40 years ago too!

[@jyvben1520]

@@morganskinner3863 understand, my cobol exam was the last time i saw that code or did any cobol !

[@teekev125]

I remember the Sinclair. I used one as a prime number generator. I wanted to find the largest prime number the Sinclair could produce before the program bombed. At first, I was getting a new prime number every few seconds, to where it would take days to calculate the next number, fun days of my youth.

[@DIEmicrosoft]

Enjoy retirement dude!

[@gdt5430]

What a step back in time, I babysat 11 PDP 11/34s and 2 PDP 11/44 on a wagon wheel network. Later to be replaced by Stratus fault tolerant machines. Thanks for the memories.

[@captainsunshine918]

This morning I didn't know what a PDP was. This afternoon I'm a fan and tomorrow I'm going to need more videos on it!

[@erintyres3609]

Just wait until you see its lunar lander game.

[@kerryedavis]

Start with the PDP-1.

[@bigbadwolf1966]

Excellent, most excellent. There can never be too much coverage of DEC hardware.

[@rogerp5816]

Hi Dave, I'm a PDP-11 fan, specifically the PDP-11/40 running RSTS. Please make some more videos showing your adventures with the PDP-11/34. If memory serves me correctly, when you pull out any of the rack drawers with the cards in them you can pull the "T" handles on both sides forward and that will allow you to rotate the draw with its backplane and all of its cards 90 degrees so you can easily access the bottom to see all of the wire wrapping. If you need to put that wire back on the backplane there are wire wrap tools and wire radially available on eBay and other places.

[@jyvben1520]

radially or readily, nice typo or my mistake ?

[@paulreading8980]

Youngster, I used to code on an 11.34 and I used RT11 but eventually we upgraded to RSX11. I also used an 11.20 and the 11.44

[@kirkwolak6735]

Agreed. Nice to meet a fellow RSTS/E runner... (Why does VI remind me of TECO?)

[@rudiklein]

I started at DEC in the Netherlands in 1980. RSTS was the first OS I worked with. I remember that you had to prefix commands with "please" on the console in some cases. The console was a LA100. Patience was a good quality to have in these days.

[@halbouma6720]

@@kirkwolak6735 Our PDP 11/44D at high school ran RSTS/E. Some of us would help admin it (I would do the backups every week) and we programmed in Pascal for AP computing on it. We also did a lot in Basic+ and had all the programming manuals in binders in the computer room. I always enjoyed using RSTS/E. VMS on the Vax in college was a different story though lol.

[@nicktucker4916]

The PDP11 was the first computer I ever had access to in High School, found I had a love and knack for programming.. Some 50 years later I'm still at it. Thanks for a great video.

[@Jim-vr2lx]

My High School got its first computer in 1994 -- it was a commodore 64. I'm joking, but only a little bit. Seriously, when i hear about High Schools like yours and Bill Gates', I'm blown away.

[@lorensims4846]

Fun! I really appreciated that photo of the PDP-1. I read where the guys at MIT, when they got their new PDP realized it had a "scope," so they wanted to create a program to demo the capabilities of that scope. They created the very first video game, Space War, using model train controllers as game controllers. I've previously seen only black and white photos of that model. I first learned Microsoft BASIC on an Ohio Scientific minicomputer that our tech school had in a back room. For seven years I was the operator for a series of IBM System/34 and System/38 minicomputers. For five years after that I was the lead operator of an IBM AS/400 Model 70 supermini shop. We were trying to demonstrate we didn't need no steenkin' mainframes. But we were pushing those machines hard. The guy from IBM said we were considered to be "hot-rodders." I would love to see you boot up UNIX on your "new" machine. They invented C to enable them to port UNIX to different computer architectures.

[@20chocsaday]

Basic was the O/S for my printer so I learned to put a prog together from that.

[@christopheroliver148]

@@20chocsaday Funny. I've had the idea, for hack value, of implementing BASIC in PostScript using printer readback for interaction.

[@NevsTechBits]

Hello Grandfather Dave! Thank you for pushing the world forward so I had a digital playground ^_^!

[@jimbatten1927]

One of the first computers I ever worked on. I performed maintenance on these, their punch tape readers, tape drives, monitors... ect. Regarding your disk drive, their heads would drift out of position on a regular basis. If not realigned every six months or so you'd find that disks archived a year or so back could no longer be read. The same would happen to the reel to reel tape drives, a real pain when trying to recover a crashed disk. Thanks for the video and memories.

[@richlaue]

I was on the final assembly and testing of Perkin Elmer computers. These where about the same size.

[@rogerp5816]

And you need a special head alignment disk and two channel oscilloscope with a special diagnostic program running.

[@prestongivens3594]

Yup, keep up with your cross-media compatibility tests, frequently. You should be dreaming about cat-eyes!

[@halbouma6720]

That may have been what happened with our PDP 11/44 in high school in 1988. It started crashing and us students who helped admin it to do a backup restore and had our boss (teacher) call out a tech who first didn't find anything wrong. Which got our boss mad at us because those calls weren't cheap. Eventually the tech on another visit determined it was starting to read/write 256 bytes more than it should with every request. I was told he replaced the controller, but it could have just been the alignment issue.

[@bradlevy2733]

It brings back fond memories. My first job out of college we had a PDP 11/34 running RSX11M, used for engineering (cross compilers and simulation) as well as downloading programs into and providing the operator interface for a tester for the custom avionics LSI chips our lab designed. The tester was interfaced via the DMA interface. A few years later at another company they were selling some old engineering equipment including portions of a DEC system. I bought an RK05 drive + controller + ~10 drive cartridges for about $150. I still have that down in my basement, though never got a system to connect it to. I had notions at one point of turning the head positioning mechanism (with its massive structure and positioning system with precise feedback) into an actuator for a subwoofer.

[@FSX239]

Digital was one heck of an engineering company back in the day. Second to none.

[@dosgos]

Where did all that talent and know-how go when the mini-computer industry faded away?

[@timradde4328]

@@dosgos Most went to Compaq and then HP. Compaq bought DEC and HP bought Compaq.

[@LangleyNA]

@@dosgos To other places within the industry. Once you start computing, you don't often stop computing.

[@LangleyNA]

Also. Engineers are engineers. They don't stop engineering and designing. Brainiacs.

[@LangleyNA]

They keep on problem-solving! The talent went nowhere but on to more problem-solving.

[@themidnightbandwidth]

You bring invaluable history to the forefront of access and reach. keep on diving deep Dave. Thank You.

[@denise39plus]

The first computer I ever got to play on was in 1977 and was an 11/34. I was located in an office in Adelaide South Australia and the 11/34 was in Sydney New South Wales Australia, over 720 miles away. My access to the 11/34 was via a Decwriter LA36 printer/keyboard. The cost of interstate data links in 1977 was enormous, so my link had to be only 300bps and was only available between 12 midday and 1pm and again between 4pm and 5pm weekdays. The government monopoly telecom service would use a manual switchboard operator to plug in the link at the required times each day. Needless to say this often didn't occur, so I would complain and after a while they simply left the link up permanently. As a result I got a full time connection between Adelaide and Sydney for 1/20th of the normal cost for several years, so I was able to play on the 11/34 all night and all weekend, which I often did. Thank you so much for this video and yes I would just love to see anything more on the 11/34 you would like to make.

[@AtanasPaunoff]

I'm born in 1978 but I believe I understand your journey. I had similar experience with the modems here in Bulgaria in the 1990's. Yes, the speed wasn't 300 bps but to be able to achieve something over 14400 bps I had to change to foreign straight phone line because our was duplex. (For the reference of the uninitiated, this means a line that is used by 2 households and has a relay that selects the active user at the particular moment while the other is disconnected.) So this type of line significantly degrades speeds and I was pushed to find a solution LOL I am sure nowadays kids would never understand this struggle no matter how colorful you are trying to explain this to them :) 🙄

[@jimmeade2976]

Thanks for the interesting video, brings back memories. Back in the 1980s, my company had a PDP 11/70 that we used for software development (Assembler and FORTRAN), running RSX-11M. It was a very reliable machine that housed several customer projects at a time. After building on the PDP, we transferred the software to customer-deliverable equipment for data configuration, testing and shipment. One such system was a control system for a rail transit system in Europe: 6xMicro PDP 11/73s arranged in A/B configuration for redundancy in 3x6-foot high racks: A-rack, I/O rack, B-rack.

[@eduardofukay]

I only have seen the PDP-11 as a number cruncher for Mass Spectrometers. In the 1990s I was a field engineer for Hewlett-Packard and VG Mass Spectrometers, so there were plenty of these machines collecting data and crunching numbers to present the graphic output. It is always good to see a "Lazarus" booting. Lazarus have come back from the dead. One observation. I would very much take care of static discharge when working on the boards. It is worth buying a carpet for you to lay down the boards and use the grounding straps. I am very happy it worked for you.

[@k.o.0]

Yes, my dad had a PDP11/34 in his lab connected to a mass spectrometer. What you described was its exact roll. He told me it was very pricey and the annual maintenance contract was also costly. Fortunately in Canada the Federal Government was paying so it was treated very well. I believe Dave indicated during his board pull that one was a A/D board, so that’s likely the board interfaced to the mass spectrometer. Hopefully he can pull up some m/z (mass to charge) spectrograms. Looking forward if Dave can dig up something off his machine especially if related to mass spectrometry.

[@jimsteele9261]

Back in the 70s-80s I was a field engineer for Burroughs. They sold a high volume laser printer OEM'ed from Xerox. It used an 11/34 as a controller. There was a 9-track tape drive for reading print files from the mainframe and a disk pack for software.

[@ericmyrs]

Fortunately, even at my impoverished Uni, when I started using HPLC, GC and MS (some of them even by HP), they weren't running of PDP-11s.

[@richardchapman7860]

Hi there. Just watched your video. Brings back memories, I was a DEC repair centre engineer in the 1980s doing component level repairs to all the PDP11 range as well as VAX. I've got a couple of tips for you. Firstly, always use ESD protection meaning a wrist strap and proper anti static workbench when poking fingers in or removing parts from your machine. Please don't tell me they won't be damaged by static, they will be. Secondly, no need for flow control on your VT220 if you turn off the smooth scroll option. It will keep up with the 9600 bps output. Looks like you're having some fun with your 11/34... keep it up. Great to see one running again.

[@kerryedavis]

Yes, the flow-control thing didn't make sense to me either. You'd likely need that for any kind of printing terminal, but not for a CRT especially at like 9600 bps.

[@whothefoxcares]

Somewhere in the Specific Northwest, an unregistered PDP-11/34 hit a Tesla Truck head on. Only one survived.

[@DeVibe.]

The Tesla

[@Altoimage]

As a supercomputer engineer we actually have specific lifting rigs by rollalift to move our Crays.

[@fixinah]

If it reboots in less than 30 minutes it's not a computer, it's a toy. - Old bearded man I used to work with at Scania in 2010.

[@nikstalwart]

By that logic, anything running Windows 11 is, in fact, a computer.

[@R3AL-AIM]

@@nikstalwart I don't get this. Power button to boot is like 10 seconds and I can open whatever I want lol

[@renascence239]

@@R3AL-AIMfast startup enabled is cheating, it’s basically sleep

[@techobservations8238]

well we could just start a few of the devices with ferrite core memory by loading the IP and starting clock lol

[@kirkwolak6735]

Funny you say this. Just before DEC Magazine became the VAX Magazine, they accepted an article from me, on reducing boot speed to < 30 seconds for the PDP-11/34a. My trick was to change the defaults in the O/S source code for the terminals to be our settings for 28 of the 31 terminals we had. So we got rid of ALL of the TERM SET BAUD 300 ... Lines. Then I rewrote the numerous one line commands for the UTILTY short cuts, etc. etc. To be a small assembly language program that read in one file for each set of settings. And processed them without loading/unloading the same program 20 times in a row. I also pointed out that if you could not change the "SIL" (compiled OS). Then you would benefit from changing the terminal command to operate on a RANGE of terminals (2-28) and allow multiple settings with a "delimiter". Again, running a program once, and setting 28 terminals in a loop. Versus launching a program for each setting for each terminal. Although the article never saw the light of day. It was very educational as a High School Student to learn to write, re-write the article. And to thoroughly test the code. Add timing to things, and figure out that the Assembly Language helped, but the biggest thing was simply loading one program to do all the work with one invocation. Once I learned that... I was PUT OFF by how the original startup file was setup to do the exact opposite. I knew from those days 40 years ago. I would do this stuff for life! And I still love it!

[@dennisjorgensen344]

DECee:badge:19220. I was an instructor in the mid-70s on the KL-10 (DecSystem10) and 11/40 teaching techs how it worked and how to repair. The Large Computer Group was based in Marlborough MA. One Ken Olson story from that era. He was famously “frugal”. He drove the cheapest Ford Pinto. One day he was visiting the production floor. One of the techs anticipated his walking by and super-glued a quarter just off the walking path. Sure enough, Ken couldn’t help himself. A legend was born!

[@ahseaton8353]

Brings back memories of an old 11/34 in an Arkansas paper plant way back in the 80s in my first job out of school. Many stories of visits there for upgrades and installs. Some fond stories, some not so fond, some just plain stupid. Please do more PDP-11 videos.

[@nathangillmore5064]

@ahseaton8353 where in Arkansas was the paper plant?

[@NoBody-xg1wg]

I was a Software Specialist, later Consultant, for DEC Software Services from 1985 to 1994. PDP, VAX/VMS, MicroVAX. VAXClusters. Later X Windows/UNIX Partner (DECStations/DECServers (MIPS)), later Alpha, with international support responsibilities. Challenging work, exhilarating. I remember ALL of them. Now retired after 9 years with Apple Inc.

[@garry4086]

I started my IT career by using a PDP 11/70 running RSTS/E in high school. I loved that machine, just about everything ran on DEC Basic. I still remember using PIP commands to set files attributes to move my programs into the 1,2 account so they would run privileged. I miss those days.

[@christopheroliver148]

Sometime I need to port the old Star Trek for VT52 to something a bit more modern. BasicPlus and the explicit VT52 escape codes are a bit annoying to figure out having not used that part of my brain for over forty years.

[@SkipInPerth]

@garry4086 ditto ! A similar road travelled for me via a high school with only 1 Teleray terminal + dialup 300bps modem to an 11/70. Yes I remember using peripheral interchange program (PIP) too. There was a large library account of game and education programs in "basic plus" had star trek for vt100 no need for escape codes of course. It was just the thing to motivate a teen to start teaching yourself Basic ;-)

[@SparkTubes]

@@SkipInPerth Did you know the "play" command could be run while logged out? And, it ran privileged so it could play the system password file!

[@albing1397]

RSX11M fanboy here. I was involved in a project (1980,s) using PDP 11/23. 2 RL01 disc packs. Learning how to navigate using RSX11M was a great learning process to understand multiTasking. Later PDP's used in Process Control Systems. Suddenly PC's, but the DEC training gave me a giant boost.

[@JeoshuaCollins]

"Brand new PDP-11" I laughed for a good 2 minutes.

[@jas88cam]

Still under warranty, right? Wouldn't want it breaking and struggling to get parts... I wonder if the warranty registration card would work? Just imagine someone's face getting that...

[@SMFJose]

Do. you like bananas!

[@robertcheek3858]

OMG, what a flash from the past! Spent many hours integrating PDP-11s running RT11 to my company's I/O hardware. We produced rack mounted I/O that included discrete I/O, relays I/O, optically Isolated I/O and analog I/O for use in process control. Our group was "Hardware System Integration" or as it was most referred to "Rack and Stack." There were loads of these machines used in process control making everything from Glass to Gasoline and even Peanut Butter! Really enjoyed the post.

[@unclerojelio6320]

Man, the mention of wire wrap brings back some memories. I spent years doing this back in the day.

[@EngineMisfire]

The backplanes of these machines were probably made in Kanata, Canada.

[@johncorvin6739]

I agree. I was hit with a wave of nostalgia at the mention of wire wrapping. During my college projects in the mid 80s I was wrapping (and unwrapping) probably a zillion little blue wires, and found that the curly pigtails of unwrapped wire wrap wire when tangled with carpet fibers are almost impossible to extract from the carpet. Good times!

[@SeattleCoorain]

Wire wrapping with all the myriad pretty colored thin wires was actual fun ! A lost art today I imagine, mores the pity.

[@dammersr]

Just wonderful. My first machine (as a student intern at the lab where my father had been IT manager before) was a PDP 11/44. When I came back full-time after graduation, we had an 11/70, then various VAXes, a Pr1me 750 and an IBM 4341 (running VM, which was my baby to manage). I love seeing your videos generally, but this old DEC kit is just heaven. Thanks!

[@gpTeacher]

Congrats on a fantastic adventure Dave! When I was in Grade 12 in Ontario in 1983 we go one donated to our high school. We were in heaven! Keep on your great PDP journey! "And when in doubt, reinitialize the MUX!" (Oops. That was for an HP Mini at Environment Canada )🇨🇦

[@MarkoVukovic0]

This is such a privilege to see someone like you make these vintage machines work. Can't wait to see what you do with it! Thanks for the great content!

[@marksterling8286]

Love your videos, love them even more when it’s retro tech. Pdp video are my absolute favourites

[@adrianpurser]

My first job was programming a DEC PDP11/34. I have memories of the daily backup that involved a printer terminal, spinning down discs and then taking them to a fire safe in another building. Happy days

[@zonegamma8197]

Very cool machine and project, will be watching for sure Please show more about this computer

[@TurningoffyourGaslights]

I suspect an ENIAC would be a lot heaver...but then I haven't seen all that many of them on EBay lately.... . PDP-11s...a walk down memory lane. We had two of them in the early days at my workplace, eventually placed into storage...and ultimate fate...unknown. I didn't have enough tech knowledge to appreciate what they were at the time, but now...I'd love to have one. 120v@24A...2.9Kw....geeze. Fascinating watch. Thank you for posting this.

[@markmoore9486]

One of my favorite computer memories is playing Adventure on a PDP 11/34 at RCAF HQ in Ottawa, Ontario circa 1977. I think I have a spare wire wrap tool somewhere if you get desperate. 😊 Ideas for what to do. Go on a tour of Colossal Cave.

[@dennisgray4432]

Apologies if this has already been mentioned, but to avoid having to wire-wrap continuity across the backplane, we used un-jumpered backplanes and 'grant continuity' cards. That way if you had a nearly empty backplane, you populated the empty slots with 'grant cards' and when you wanted to add cards to the backplane, all you had to do was pull the grant cards out and insert your muxes, memory or whatever. The grant card was only one slot width and we used to carry 'em in our back pockets. Very handy when you had to pull out a DH-11 for repairs...! Oh and BTW - yes to more DEC content! Would love to see you fire up RSTS/E on that 11/34! Ahh the memories....

[@_masteryoda]

Sweet. I ran one of those at work, back in the day. So excited to watch this one. (actually an 11/44)

[@jerryvelders4457]

My second programming job was for a timeshare company running a PDP11-70 RSTS-E back in 1981... Cobol, Dibol and Dec Basic. Great hardware and software for the time. We also got a Vax when they came out, but I didn't have much time on it. Great video. Great memories. Thanks.

[@randaldavis8976]

I almost bought one at the DeAnza College, Cupertino CA swap meet in 1980 $800 with 2 disk drives (removable). Wanted to run a multi line BBS. Never got to run one at work, We have Vaxes, lovely machines

[@strehlow]

My Assembler class in college was taught first on a PDP 11/17 running RSTS/E. That was the most elegant OS I think I've ever used. The machine had 32K of RAM, and nearing the due date of a project, there would be upwards of 40 people logged in at once. I couldn't tell the difference from when there were just a couple of us. There was a command (which I can't remember) which would create disk files of arbitrary size. It had a switch that would prevent zeroing out the data. So I figured out how to snoop on the other people's assignments by creating files near the size of the free space, then scanning through them for assembly code. We had disk quotas, but it was only enforced when logging out. So I could rummage around un-allocated sectors as long as I deleted the files before I got off. Fun times!

[@warrengibson7898]

I believe PDP stood for Programmable Data Processor. Divisions of large institutions typically weren’t allowed to buy computers, hence the disguise.

[@yoursred]

Why weren't they allowed? You got me curious

[@warrengibson7898]

@@yoursred presumably because the stewards of the centralized computer installations were jealous

[@JafferManiar]

​@@yoursredIBM was a huge monopoly and there was a saying "Only IBM made Computers" Hence, Dec marketed it as PDP and Wang Labs made "Calculators" to protect themselves from being bought up by IBM

[@paulalmquist5683]

I know of a department that bought a model PDP8 Oscilloscope as they were not supposed to using computers. Order was signed by the boss who never caught on. The salesman was happy to play along.

[@kevinL5425]

The story I heard is the venture capitalists in 1957 thought a “computer” was the huge room filling million dollar systems dominated by a few companies like IBM, UNIVAC, etc. Nobody wanted to invest in an unknown small startup company with only a dozen employees to compete with those huge established companies. So DEC didn’t build computers. Instead they made Digital Laboratory Modules / System Modules that could be plugged into a backplane in a cabinet and connected together in different ways to make specialized laboratory equipment. The fact they just happened to also sell the “Programmed Data Processor” (PDP) cards that would help coordinate their Analog to Digital, serial, disk drives, and other cards was just a “coincidence” … at least to the investors.

[@peterrabbit4034]

My college had a PDP 11/70 as the mainframe when I was there, but there was a PDP 11/40 stored in another room in the data center. This brought back so many memories.

[@CandyGramForMongo_]

“I don’t know how to wire wrap.” Finally! Something I’m better than Dave at!

[@russellfinch5493]

Ex-DECie here. Started in 1976 and lasted until 1993. 11/34 brings back a lot of memories. I had an RK05 head crash overnight and the cabinet was full of shredded metal in the morning. Made quite the noise. To be honest though, the 11/34 was heavy but you are talking about the entire cabinet and not just the 11/34 box. Now, let me know when you find an ESE20 which is DEC's foray into solid state disk drives. I built them. Each memory board in the cabinet was 2,500 dollars. The single disk drive was only $120k. Still have the manual. I also wrote the build process. It was the fastest thing going at the time. Now that was a cabinet as the backup power supply (UPS) was heavy and took up about half the cabinet. I worked mostly on the tape drives until we started building the ESE20 and also built a bunch of the failed PC line. Anyway, thanks for the video. Brings back a lot of memories. Best company I ever worked for. Ken Olsen was also the kindest man let alone a CEO. Criminal what the board did to him in the early 90's.

[@kc5402]

WOOHOO! (Sorry, I couldn't stop myself! I just got to 26:45 and the DIR listing appearing! I'm so absorbed in your storytelling Dave that I feel I'm actually there with you! 😂)

[@DavidtheSwarfer]

me too, I updated a BIOS the other day, from the 2014 version to the last one, 2018, (to get UEFI working) and it booted right up and I was PLEASED (-:

[@allyouneed71]

I was surprisingly elated at the successful execution of that most basic of commands

[@jcampbell2481]

Working in a Nuclear control room in the 1980's/1990s; we used PDP 11/34s first until they was found to be too light duty so they were replaced with PDP 11/70s. Very reliable machines. Disk drives were huge. Good times!

[@cs233]

As a retired tektronix engineer who started in the PDP-11 era, I’d say if you can find an old working tektronix direct view storage terminal (dvst) and the software you could load the old lunar lander program that simulated landing on the moon from orbit and displayed the lander on the terminal. Used keys to control engine thrust. Don’t know if it would work with a current generation terminal program that has a tektronix graphics emulation mode or not. I wasted hours with this. Surprisingly hard to land in one piece! There was also a text only adventure game. Can’t remember the name, but you could explore and pick up treasures to use in future battles. I remember I keep getting stuck in the maze of “twisty turny little passages, all alike” - assuming I could get through the maze of “twisty turny little passages, all different”! Spent hours on that one, and I don’t even like computer games! Of more modern games, the only ones I ever play are solitaire and occasionally Tetris!

[@Harrzack]

That game was “Clossal Cave” by Willie Crowther. I had a version written in Fortran (including Source!). I was the one (by a real stroke of luck) to finish first. Charle Drum - are you out there? It was a GRAND time and CC and the PDP-11 live as beautiful memories of mt early years becoming a programmer. 😊

[@SeattleCoorain]

In the mid-1970's my friend at Tek, an engineer in the 5000 series lab instruments division, would play I think the same cave/dungeon game on a WYSE terminal over weekends. It was addictive. We discovered if you shot an arrow at a monster and it bounced off, then picked up the same arrow, it became magically blessed with invincibility, but only if you: "wielded the arrow" at a monster not shoot if again from a bow. We stopped using that trick because it make the game too easy. Back then, Tek was one of the hundred or so nodes on DARPA-net and we had new fangled email accounts.... halcyon days.

[@ClusterFugue]

​@@HarrzackI remember the version I played on pdp-11s and VAXen back at the dawn of the 1980s being called "Adventure" and the same game eventually ending up on PC (And I think Apple II as well) as "Zork". I believe "Collossal Cave" was the same thing, although I'm not sure which is the original name. " It's so dark, you're likely to be eaten by a grue." Good times!

[@nyanates]

Love these restoration vids. IBM was my destiny but we knew about these machines and appreciated their contribution to the industry. Thanks.

[@WatchJRGo]

Thank you for properly calling it a sawzall... I get so much hate for that. "Reciprocating saw" is for losers. 💯

[@DavesGarage]

I blow my nose with Kleenex and ride a Skidoo!

[@WatchJRGo]

@@DavesGarage yeah buddy, same here!

[@johnhaller5851]

If you put a Milwaukee Sawzall blade in it, does that make it a Sawzall?

[@erfrulla]

I worked for DEC in the 80s and 90s as an RSX-11M support expert for the US Area and one of the developers of the RSX Software Performance Monitor. Had a PDP-11/74 as my personal computer. Loved that part of my career. Thank you so very much for a trip down memory lane.

[@cykkm]

3:50: $120,000 in 1960 is equivalent to about $1,250,000 today. $0x131AB8, to be exact. Yes, I know they used octal back then. I used to work on a 11/73 with a colour text display-was it VT320? VT520? I don't remember. RSX11M+. SYSGEN. MCR, EDT and MACRO-11. QIO$S. The TKB linker. SY:[1,54]. I'm surprised that I in fact remember this stuff...

[@dsudikoff]

0o4611320

[@jujuUK68]

The VT320 was a flat screen style monitor that came in 3 flavours of display; amber/black, green/black or paper white, which was fab, the VT340 was the bigger, colour monitor.

[@cykkm]

@@jujuUK68 Thank you. I remember that mine was indeed larger than VT220, but can't really recall whether it was VT340.

[@nvsv_wintersport]

PDP-11 was the computer they used when I started studying in IT way back in 1982. No terminals for first year students, but plain old punchcards. The PDP would send everything to a much more powerful machine (if memory serves me correctly that was a Cyber-205?). That PDP-11 was standing in a room where we would open the windows on warm days, so not a special computerroom with cooling, it just worked!

[@doubledrats235]

I took a computer course at Freeport (NY) High School in summer school between 7th and 8th grade. We learned on a DEC PDP-8 using mark sense 40 col. cards that you filled in with a #2 pencil. I fell in love with programming that summer. The following summer the school had upgraded to a DEC PDP-11/35 and after 8th grade graduation I continued my computer education. This time we had a room full of ASR-33 Teletypes. After class was over imagine the sound of a room full of 13 year old programmers running or printing out their programs (or playing Super StarTrek). I also took a typing course that summer which helped me years later when I worked as a programmer. I still have some of my programs on paper tape somewhere in the basement.

[@kpforceone]

I really appreciate your efforts in demonstrating/using the older hardware. I love this stuff. Keep it up Dave!

[@philipval3500]

Great story! I have a couple of grandsons (out of 5) who are on the spectrum. They are both very intelligent and one is very skilled with PC hardware. They both enrolled in college this month. I love them all.

[@ctarabocchia]

This episode brought back many memories of the beginning of my career back in 1981 when I was hired to write code on a PDP11/23 using 8 inch floppies running RT11.

[@StephenDavis-ls9nk]

177650 , 70 and the 11/70 boots... I worked for DEC from 1982 until Compaq, then on with HP. Retired after 32 years of service. My first job was learning to do RSX-11M/S Sysgens on 11/45's. Nice job with the 11/34!

[@ehwestonful]

This takes me back 40 - 50 years when I had tech jobs maintaining and repairing everything from PDP 98s and PDP 11's . Watching this video showed just how much I've forgotten over the years. Gone are the days of the Honeywell 516's, General Automation SPC-8 and 12's, and the Varian 620's. Thank you for keeping these systems alive.

[@frankwilson2607]

I love your straightforward, detail-rich explanation. Great logical approach. As one somewhere on the spectrum (but lacking your emotional neutrality) I greatly admire your ability to overcome the many challenges that being on the spectrum presents.

[@bruceclarkson1748]

Neat! I have fond memories of using an 11/34 on a real time railroad research project. I have a slightly more painful memory of setting the backplane on fire three days before it was supposed to be delivered. Minor damage repaired with a wire wrap tool. So nice that you can interface yours to a more modern storage facility. Enjoy your truly historic machine.

[@laustinspeiss]

Thanks for the trip! I worked for DEC in the 80’s, had an 11/23 at home with 2x RL-01 drives - running RT-11 and RSX-11 with a couple of terminals and printer. It was a blast seeing the RK05 dives (only 2.5 MB!), hence my lust for the RL-01s with 5MB - and much quieter without the voice-coil positioner. A great purchase in great condition, but not cheap 😱 Enjoy it ! Jealous of the 11/34

[@josephgaviota]

What a GREAT video. As a young man, I used PDP 11/30 and later PDP 11/34 as part of the ATEX typesetting/editorial systems. In 1983, in preparation for the Los Angeles '84 Olympics, I was sent to Washington DC to work with the programmers so we could receive the data for the Olympic Daily Record. We used PDP 11/34s and J11 computers on loan from USNews & World Report to produce the typesetting and coordination of stories from the field into the daily newspaper, Olympic Daily Record. Anyway, I enjoyed this history lesson, thanks a LOT.

[@TheRetroGamingPrincess]

Seeing the convergence of creators in and around the 11 family world is so wonderful. Im going to shout out BSD! :) Lets see it running that!

[@christopherguy1217]

Col video, brings back memories. When I was working on the F/A-18 program for Canada, we had a PDP-11 that acted as the bridge between the IBM 4618 mainframe running the compiler and the VAX we used for all other work. That thing was a tank, never failed.

[@zos007]

My IT Career started in 1983 as an operator using DEC PDP11 24, 44, 70 on RSTS/E and also VAX 750 and later onto 8310 Cluster (a true clustered system) and then to MicroVax. These were fantastic years ❤

[@AdvistaVideo]

Wow that brought back memories. I was a computer tech back in the early 80's and remember servicing the disk packs using an oscilloscope to align the heads. Proper air flow is very important for the heads to float above the surface of the platters. Very cool to see it working for you.

[@brianmurdoch5062]

Oh what great memories this brings back from my years at the DEC Ayr, Scotland manufacturing plant and the PDP 11/34 and so many other PDP 11 and Vax systems we produced on the FAST (Final Assembly and System Test) lines.. Cutting the CA1 to CB1 wire was needed for every DMA card the customer needed, so it became second nature after a while. I carried so much knowledge and experience into field service with me from manufacturing and it served me well. This is a great video along with the accompanying explanation of your issues and resolution. To get it all working is a fantastic achievement, well done.

[@PhotographyEnthusiast]

OMG, I have just stumbled across your channel and took a trip down memory lane. I worked on pdp 11's with rsx 11m to control coal mine automation systems in the late 1970's. The visuals, operation and your amazing story have brought back a flood of forgotten memories. Thankyou. ❤️😁

[@ddichny]

You mentioned several operating systems for the PDP-11s, but you didn't mention RSTS/E, which my college used on a PDP-11/70 to timeshare countless students through the late 70's and early 80's. I found it much more user-friendly than RT-11 or RSX. That 11/70 had the lovely purple/pink front panel, I still get nostalgic when I see it in a video or old photo. I also recall one time going down to the computer center and seeing them upgrade the computer's memory. By today's standards it was a trivial amount of RAM, but at the time I was very impressed by the massive new boards they pulled out of what seemed like extra-large pizza boxes.

[@egillis214]

I worked as a sysadmin in PDP 11/70 and this was great to watch. I did Fortran 77 on old paper tapes and Basic on 8in floppy drives. Homework was printed on dot matrix printer and graded as raw code & hard copy results

[@bohenriksson2330]

Brings back fond memories of being an aspiring computer nerd many many moons ago 😊. Thank you 🙏🏻!

[@christopherreeve1502]

My high school had their PDP 8 stolen the summer before I entered, replaced in 1981 with a PDP 11/44 with RSTS/E OS. We used Basic Plus and a Pascal compiler to program typical educational exercises. Project I remember most: wrote a program to renumber all or sections of a Basic program, renumbering lines themselves and references in if/then, goto, etc. statements. 😊😊

[@The_Oldguy]

Back in the 70's I worked on the Lockheed SUE mini and in the 80's I worked for Xerox Printing Systems, and we used the PDP 11/34 as the controller. Great to see the electrons still spinning!

[@Drycleanerguy]

Nice to see you exploring yet another bit of my history. In college, I programmed in assembler on a PDP-8e, which was octal, and somewhere I used to have full schematics of the logic flow of a PDP-8e. In one of my first jobs, in addition to sometimes operating an IBM 360 mainframe, I programed in COBOL and assembler on PDP-11s, mostly 11/23, 11/34, and 11/44s running either CTS-300 or RSTS, and having RL01 drives. I never got into the hardware, but I think they were newer models than you have, from circa 1980. I do have a vague memory that at the time, 64KB of RAM was about $8000, and a 100MB 12" or 14" hard drive was $30,000. As far as wire-wrapping you just need a wire-wrap tool, after which it is easy. FWIW, the oldest "PC" I've seen was a MonroeBot, but while it appeared to be complete (in 1982), it was not operational. The same guy also had some old magnetic "core" memory from mainframes.

[@fredbergeron1249]

Love these DEC episodes. The first computer I was exposed to was a PDP-8 in grade 9 where we learned to do simple programming with paper tape. At college we had a minicomputer class where we did software and hardware on an 11/70 and 11/34. In third year we build add-on memory for the 11/70. My first job was doing airborne geophysics and the system in the aircraft incorporated a ruggedized PDP-8 clone. A subsequent job involved programming and supporting a LSI-11 based on-stream x-ray fluorescence systems for mineral processing plants around the world! Many years of hardware and software fun (RT-11, RSX-11, Assembler and Fortran). These DEC shows bring back a tidal wave of good memories so Dave please keep them coming!

[@mitchalsup5607]

I can still remember the input toggle switch sequence to boot my PDP-11/20 from paper tape. {{Where my DPD was owned by CMU in the EE laboratory.}} Truly a machine ahead of its time.

[@holyngrace7806]

I started out on a DEC PDP11/5 ! Wonderful to see this project and the system working! Big CONGRATS!

[@TheAzguardThor]

Takes me back to my days in Operations 11/34 44 and 84 ..... wonderful memories . :)

[@NeverlandSystemZor]

I love these are called "mini" computer.... This is so cool. Love that you could do this and save this history.

[@tinman5322]

I have only the most superficial knowledge of this stuff but was captivated by your process and appreciate the brisk pace.

[@jessejames586]

I had a pdp 11/20 in a full height rack with tape drive, paper tape reader, power control unit, etc. I gave it all away years ago. I worked at Dec for 28 years starting in 1976. This brings me back to a time when computers were computers with massive storage drives, printers, etc and heavy as Hell!

[@marknichols2027]

In 1980-84, I learned assembler, Fortran, cobol, and basic on the PDP 11-34. I eventually worked at Microsoft and all throughout my career I used what I learned on that machine. More videos please!

[@XxXaRvoxXx]

Just brilliant, simply marvelous! Im about 20 years too young to have nostalgic feelings about these machines but i always had a soft heart for those vintage big iron machines. If i could afford the electrical bill i would certainly try to get my hands on one, but sadly im forced to "tiny iron"-machines. But im starting to consider a blinkenlight panel for my raspberry pi, maybe even a paper tape reader/puncher just for the giggles. Thank you kindly for sharing, and a enormous thank you for being such a great role model for those of us on the spectrum!

[@PhilipCrichton]

Thanks for this. My early career was programming Fortran on a PDP 11/44 running RSX-11M Plus. Ah, the memories.