Data General MicroNova Teardown
HTML-код
- Опубликовано: 30 июл 2024
- I'm finally starting the process of getting into the Data Generals and seeing what exactly I'm going to have to do to refurbish them. This was the beginning of what will be a long journey of working on the Micro Nova computer!
You can see my notes from this here: caps.wiki/wiki/User:Akbkuku/p...
Here are some ways to help me make more videos!
Buy some Merch:
Merch: tech-tangents.creator-spring....
Leave a one time tip:
Paypal one-time: paypal.me/AkBKukU
Ko-fi: ko-fi.com/techtangents
Amazon Wishlist for Production Gear:
www.amazon.com/hz/wishlist/ls...
Become a monthly supporter:
Patreon: / akbkuku
RUclips Membership: / @techtangents
Paypal Monthly: techtangents.net/support/
Other Links
RUclips: / akbkuku
Twitch: / techtangents
Github: github.com/AkBKukU
Thingiverse: www.thingiverse.com/AkBKukU
Discord: / discord 
Наука
![CENTRAL CEE - GEN Z LUV [VERTICAL VIDEO]](http://i.ytimg.com/vi/VIbidJm9q34/mqdefault.jpg)
This was an experimental video for me, I needed a bit more time for the next main video and decided to try editing a live stream down to a normal video. This has some rough edges a lot of which are because this was my first attempt at this. I have a few things I'll do in the future if I try this again and I think I will because I can see this working well with some changes. I was recording the cameras individually on the streaming computer but the quality ended up being very poor so I had to use the main live feed here. In the future I'll need to record in each camera separately. I think I may try to get a second good camera to replace the gopro on the arm as well since it was the active camera the majority of the time. And if I can plan a little better to explain things and give it a better intro and outro it will feel a lot smoother. So consider this more of a proof of concept than a final product, I will be refining this more in the future.
Loved the video, been excited to see the Novas get some love since you first showed them! I'm really excited for the videos, especially if they are only getting better from here out!
For you calling it a first effort I think it was pretty good! I enjoyed it.
This edited down stream is so welcome! I cannot devote myself to a couple of channels, much as I like this one, meaning hours-long streams are just not for me. Same happens with, for instance, Mac84. I see the subject, and I like it but it's either watching that only or half a dozen videos from other subbed channels in my feed on any given day, so... I'd like to see some more of these in the future. Thanks!
Love to see more stream summeries. I'm alway interestet when I see the steam upload in my subscribtion box on RUclips but don't have time to watch them.
I think the battery backed ram was a fix for not having core memory anymore. Minicomputers had the ability to shutdown with programs in the core that you can bring the system back up with memory intact.
3:28 I nearly spit my lunch out, that was an awesome surprise!
I can't tell you how stoked I am for your Data General build! Here's hoping your drives don't have head crashes as rough as mine, granted you really have to try to have a head crash worse than the one on my Hawk, haha.
Have a busy job and then a baby, these short formats are very much appreciated!
I like the shorter format, since I don't have time to watch the live streams but hate to miss the show
The Data General operating system was known as RDOS - for Real Time Disk Operating System. This appears to be a more recent multi-user computer.
The Nova 1200 and Eclipse computers I worked on were foreground/background only.
I'm sure they had support for Fortran, but we programmed in assembly language only.
The o/s prompt on an interactive terminal was "R" for Ready.
I used both Nova and MicroNova systems starting in ~1979. Fun to see these machines!
This machine is so interesting, what a fab thing! It's amazing, and is obviously the ancestor of the desktop PC, even the case is a similar size. Power supply, system cards and cooling fans. Just missing the modern I/O ports. Never seen anything like it before and I am absolutely confident that you will get it to function. 👍
Loving the latest content! Glad you get to finally check out the beautiful blue behemoth. The shorter summary follow ups are great, but please don't stop posting the streams, they are great for my long commute when I can't catch the stream.
I worked on a DG Nova 3 and 4 system. The application was a A/V editing control system named "EPIC" manufactured by Consolidated Video Systems, written in the DG assembly language, designed by Larry Seehorn. The RDOS and 6045 HD was used just for the development, each customer copy booted from a 5.25" floppy with an expansion chassis for the VTR interfaces. It used a Lexicon Lexiscope 2000 character generator "15x15" PCB that plugged into the Nova. It also had a custom, color coded keyboard.
I'm currently refactoring the source code to organize it into pseudo classes. I comment every line of code in the context. I sold all but one Nova 4 many years ago, but got another 6045 HD that needs work, plus I don't have the daisy chain interface or cable so I will have to build or find those to get the system running again. I plan to create a solid state memory that emulates the 6045, so that the RDOS will remain unchanged. Using 6045 always made me nervous, worrying about crashing the heads, losing data etc. I also plan to link the Nova system to a PC with a serial link so that editing and backup can be done on the PC and only the assembling, linking and writing to the 5.25" floppy would be done under the RDOS.
So glad you're sharing this journey with us, I've been enjoying all the videos so far.
Man, this is fun to watch along on your learning journey as you dive into a Nova for the first time. These things are built so very different from other vintage computers, and there is alot to figure out. You've off to a great start.
The point of the ESD band is not just to ground you temporarily. you have to keep it on at all times. It also slows down the speed of the electro-static discharge
I like these edited videos, as much as I like the main videos and the quality you usually put into them, content from you in general is great to see!
On the plus side, all this dust might of protected the connectors from oxidation and corrosion over the years of storage. Just getting all the dust out now is gonna suck.. but better then fixing corroded traces..
We just have to hope the disk drives are ok now..
This is the stuff I’m looking for, man! Loving it!
High quality early-mid 80s caps are fine. Just ESR test them and bring them up on a variac and they will be fine. Really the variac is just being hyper cautious. They were high quality to begin with and have lead a fairly easy life in an actively cooled rack.
Love how this is coming along! Wish I had the room for a mini computer right now, maybe I should turn my attic into my room for one! LOL
My dad worked at DG from the mid 80s to the early 90s. We have an old video of him and some of his office friends making parodies of various TV shows and commercials within the data general office. He still has his name badge somewhere.
Back then they weren't 120mm fans. They were 5 INCH fans. It was American tech, built in the USA. Ram chips made overseas were a crap shoot, so we tried to keep it all good ole American made.
The thing I find great about this computer is that a rpie is more powerful and could run off those huge caps for days
Those sealed AGM batteries are actually very stable, there would have to be physical damage to make one of those batteries leak, extreme overcharging or physical shock etc
It looks like it is a linear PSU. So the card will have a lot of the voltage regulators on it. The big caps.will be the smoothing caps for the inputs to the regulators. The big transformer will be what supplyes the rectifiers for the big caps.
as soon as you wore that ground bracelet, i knew you had the faustian spirit
This is very interesting. Those caps. Wholly moley.
This is the best April Fool's joke ever!
No but seriously, this is really fascinating, thanks for uploading.
This is very interesting! Have there been more progress videos? Can’t seem to find any. Anyway, good luck and much success with this project!
Another way to label those two pins that take battery power into the CPU card, would be to get something with the same connector (eg: PC front panel wiring or cheap breadboard/Arduino jumper cable sets), cut the wire to a short stub, and shove it onto the same pins.
The wire wrap jumpers are around boards that don't carry the interrupt line through.
You need to get this thing going just good enough for Druaga1 to add an SSD and Windows 98!
The multi pin plug for the power supply input voltage. Will be wired to select 120volt or 220 volt input. As this is a standard linear PSU. The big transformer. Can be wired for 120 volt or 220 operation.
follow up on my comment on the other video from the 18th (iirc) - Fans- yes once you power up the squirrel cage and devices in one rack you will need hearing protection! Those fans are LOUD. There is a connection between the fans and the caps though that you wouldn't expect. We had Eclipse C330s and we did a lot of board swaps etc. The C330 was a much bigger chassis, about 4u for the main chassis and an expansion chassis was bolted to the bottom making the entire assembly about 8u high and probably about 100-150lbs with the boards removed. The power supplies were in a space between the board slots (that opened to the side requiring the chassis to be slid out of the rack to remove any of the 15 inch boards) and the rear outer wall of the chassis. The rear wall of the chassis had six of those 'boxer' fans on it. When working on the very expensive 1meg (word I think) boards when we did an upgrade we would pull the unit out on the rails, and pull the memory boards to swap them. We blew two in a week and had to call in the service people to see why.
They explained that our process was faulty because even with ground straps we were shocking the boards because of the capacitors. There were about eight capacitors in two rows under the card slots and above the expansion board. Each was literally about the size of a soda can! The ones you are saying are huge would be their babies. Anyway, we weren't letting the caps discharge enough before removing and inserting a new board. The solution was in the fans. Powering down the machine would cut power to the fans but they would slowly spin down. We would watch until all six fans stopped and then pull the card.
BTW the procedure to change the fans when they died was as follows- 1- power the chassis down, and remove all cables from the back, 2- slide the chassis out and remove all cards from both chassis. 3- get four strong men to unlatch the rails and slide the chassis off, carry it to the table and put it down. 4- unscrew the top and back panels 5- tilt the power supply components away from the fans and unbolt and remove the bad fan 6- replace fan and reassemble power supply, then reverse steps 1-4.
This obviously took time on a weekend so when we lost a fan we would cable-tie a boxer to the rear of the chassis on the grill and power it with a direct plug to the rack power until we could schedule the change.
I helped with that at least four times over five years!
I wouldn't mind having a microNOVA or one of the later computers which used the Fairchild 9445.
You need to add some moist paper towels to your wishlist. ;-) That cage needs a good wipe-down, like 20 years ago! I don't know how you can stand working on something that filthy. I always have to de-gross stuff before I'll tinker with it. haha (Unless that's authentic vintage dust?)
This was a fun watch live ^^
Honestly for the power supply I'd just try matching it with modern parts. That dated pos is going to be pushing out mad dirty power.
Thank you for editing the steam down. I like watching your progress, but can’t watch the stream.
I was checking to see if you had anymore videos about the Data General minicomputers. It's been 10 months. I just wondered if I have to look on Twitch or something. I don't follow Twitch. Well I guess I just have to wait until you put something new on here.
This is based on no actual info but that power connector looks like it's vertically some combo of live neutral ground for the 4 voltages, so it ends up being 3x4 as in the 3 for L N G and 4 one for each voltage, although I have no idea why would it be setup like that
Whelp, now I gotta follow you on Twitch!
The fans pull power off of the bus
From the looks of it, you could disconnect those caps and feed the PSU board and all it's cables out in one piece.
The dust in that computer is so bad, I started sneezing at about the six minute mark. ... And at 19 minutes I'm *still* sneezing.
Would a part washer with an electronics safe solvent be feasible?
Do you have a video on just how you document a project like this?
Might need a different plug for 220. Wondering if the wiring to the transformer may use different pin out for 220 vs 120
So I have an ESD strap. Is there supposed to be continuity between the metal on the wrist band and the alligator clip? Or is there a resistor
There's a high resistance in there, so you won't see continuity on it.
@@Zeem4 ok. I got ifixit to send me a second esd band because it didn’t have continuity. When the second one showed up the same way I thought I must be missing something.
Status progress
I'm not telling you what to do, but there's no way I would use the original power supply, even if it were fully recapped. I'd rather figure out what each wire is and adapt them to a modern switching power supply. Either an ATX one or an industrial one (from say Mean Well or similar brand). I would also replace all that wiring because the insulation is probably getting brittle by now. This is obviously a task that would take some research to be able to accomplish, though.
Not even the slightest urge to at least blast some compressed air all over it or brush some of that dust/dirt away??!
AT 24:13 what type of programmable keyboard is that?
I guess you voided the warranty on that thing?
Crudtacular
Anyone else sit through the printing to find your name (or names if you are a member and patreon)
andddd we won’t se a vid about these for another year:(((
How many microfarads per finger???
Antistatic mat?
maybe if you can get 240 will be more safe because you need lees amperage
Status progress?
I'll be shocked if this machine works.
Thanks for posting an edited down version of the live stream highlights. I used to follow some other channels which stopped uploading edited videos and moved almost entirely to live streams. I didn't have time to watch them so I lost interest and unsubscribed. Live streams are great if you're there when they're live but they really don't work well when you're watching after the fact.
Boop
This is going to be an interesting series. Contact Bruce Ray at Wild Hare Computer Systems, Inc. He _may_ be able to send you PDFs of the documentation that you are missing, maybe even schematics.
Having that chat on the screen is distracting.
Windows 10 pc build 🥺🥺🥺
What ??
As usual, live chat offers nothing constructive.
Interesting subject, but I wish you'd lose the nervous giggles intersperse throughout.