When you were taking the CRT out you held it by the neck… that’s a really good way to break the tube. You should always hold it by the body of the tube and be VERY careful to not hit the neck on anything - they are quite fragile, and essentially unubtainium now that nobody manufactures them anymore.
After the utter disappointment you suffered with the 70s Trinitron, it's so good to see (and share) your delight in getting this beautiful machine running. Very well done. +1
I built my North Star Horizon in 1978 and used it for years. Eventually I updated the cpu, fdc, and RAM boards. I still have the system and have been trying to revive it
I am currently trying to fix a Northstar Horizon that I acquired a year ago. I'm still struggling to get any output from it. I think I need to get one of those chip testers because I think something on the IO side of things is not working, or I do not have the correct boot disk. The lack of output from the system if no disk is found makes it hard to diagnose.
Not sure that was pure silicone. If it was, mineral spirits are your solvent. The problem with that is that it works so well you wind up smearing liquid silicone all over the place. I usually try to manually remove it if I can. Lighter fluid is Naptha, also available in larger volumes at your local paint store. Works a charm on stickers and adhesives in general and if worse comes to worse, pour some in your zippo and set it on fire.
Brilliant! There's a Hazeltine 1500 sitting on the shelf right next to me, waiting to be cleaned and restored. My unit has the anti glare screen coming of in pretty much the same way as yours. ;)
The Hazeltine 1500 was one of the first low-cost smart terminals, from a company with a rather interesting history. Most 5.25-inch floppy disk drives won't spin up without a control signal.
The memories. My high school had one of these terminals. It was connected to a computer that had a couple of 8" FDD and a card reader. It had stopped working. I fixed it by setting up the dip switches properly. Someone must have messed with them. It was a buzz for me as a 12yo to 'fix' such a big computer that no one else at the school could.
Boy this takes me back. I was a cop in a small North Dakota city, the locals learned somehow that I was also a computer geek. Suddenly my phone would ring as I was trying to sleep, and my wonderful wife was working at the local nursing home, some business would be having computer troubles, this in the late 80's. I worked with C= machines but these folks were using early IBM, Epson's and such, so I learned how to work with CPM and DOS as well. Now my C=128 came with a version of CPM so I played with that to get to know the language, our city Judge had an Epson running CMP and he helped me get into it as well, he didn't know much about it except how to load his software but that bit helped. One fellow had a 10 MEG external Hard drive that was HUMONGUS and weighted a TON. He sold his machine to the Newspaper but the monitor was gone, so the paper owner had me go up in his store room and print out a database of all citizens and farms that the old business had gathered to use for his plat book. Man talk about a hot noisy job but I got it done, and as a reward the paper gave me the machine, after all he just purchased it for the data. Ah for the good old days when only we few knew how to work these mysterious magic boxes!
I recently acquired a keyboard module from a North Star Advantage. The key caps are gorgeous. They are the favorite of all I own. It's foam and foil, though, which isn't everyone's cup of tea.
I used this system connected to a hard disk while I was at college learning how to program in cpm. I can remember fixing one as it blew its tantalum capacitors. If I owned it I would add crowbars to power supply rail's.
@@cairsahrstjoseph996 crowbars is a description of a circuit. Which normally consists of a Zener diode triggering a SCR across the PSU rails as though you was throwing a crowbar in to stop a machine. It is to protect all electronics downstream and to blow the fuse if the power supply was to supply more than say 5V. I have installed them in my Commodores and other vintage machines to protect them. Switching supplies usually fail safe but linear PSU don't.
@@cairsahrstjoseph996 I see you have the commodore logo so what do you do about your PSU as CBM not that reliable. Back in the 80's had a report of a machine running hot only to find over voltages. Any problems thou shalt test voltages first!
@@Electronics-Rocks I gave all my Commodores to TPUG some time ago; but, back then (2000's) I never had an original brick PSU bust a machine, although a couple of times I had a PSU fail during operation (guess I got lucky); and I didn't have voltage testing apparatus either. Never had a 64 simply fail during operation, either (more and more lucky!).
When the Hazeltine 1500 was market current, about the time I was attending University of South Florida in Tampa FL, it was very common for terminals to be positioned in rooms with anti-static flooring and pretty intense air-filtration. By the time personal computers like the Apple II and IBM AT were starting to edge out mainframes, you started seeing a more lackadaisical placement of computer hardware and the grime inside the case could get to fire hazard levels. In the mid-1980s, at Marshall University in Huntington WV, I saw quite a few Hazeltine terminals that were hooked up to the university's VAX mainframe and they were all approaching end-of-life from hard use and poor (if any) maintenance. Over the years, I've seen melting of the sealant on old CRTs and terminals pretty often. Something in the chemical composition of the sealant causes it to go all tarry after about 20 years, well past the expected lifetime of the hardware. A good deal sooner if the component has been stored in a situation without rigorous climate control like the manufacturer expected "back in the day". I don't know if Northstar ever had compilers for PL/I, Cobol, Fortran, Basic, and Pascal, but I do clearly remember doing an ungodly amount of coding in PL/I, Cobol, Fortran, Basic, and Pascal on Hazeltine terminals. :D.
Excellent video. I was expecting at least one Tantalum cap to pop though! N* used some particularly explody ones on their boards :) If you have no luck after cleaning the drives try checking/swapping the LF356 Op-Amp in the top left of the disk controller board. I've had to swap these on three of my MDS-AD3 boards after they showed very similar symptoms as yours.
We had one in the local library. You could book time on it or the MIcroBee. Dearly wish I could find one for my collection. Love this.. they're not easy to find any more :)
I did my computer college course on this baby, loved it. A Microline 83 Printer was connected. Had a Microtan 65 at home. Loved the early days of computing.
Good Grief; that capacitor is the size of a can of soup! The only ones that I can think of are bigger are the ones in Tech Tangent's Data General and the ones in early television sets, which were like shoeboxes.
Captive screws, or bolts, would have increased the likelihood of this model being able to compete for contracts for equipping ships or air crafts. The terminal looks really nice. I feel really good, watching this on a Sunday morning, eating toast, drinking coffee while also hanging up my laundry.
CP/M wasn't a clone of DEC RT-11, but it certainly drew inspiration from it. And RT-11 was influenced by earlier DEC operating systems for the PDP-8 and DEC-10. Windows use of forward slashes for command line switches and CR/LF line separators for text files can trace their lineage through MSDOS and CP/M back to DEC.
This thing reminds me of an old Heathkit H89 computer I picked up at a church garage sale years ago. It also used hard-sectored disks, and it could boot both CP/M and HDOS as its OS. A special latching key on the keyboard would essentially disable the CPU and let it act as a dumb terminal. I wish I still had it, it'd be worth a fortune now.
32:55 DQ, aside from being tasty, is probably "dual quad" disk drives, quad capacity being North Star's term for double sided/double density. On their later Advantage machine, the CP/M herald would show 2Q or HQ depending if it was a hard disk system, for example.
Great video! I think we need more on these systems that happened right at the beginning. I would love to get one of those terminals and just plug a Pi into it and simulate a PDP11 or something. 😁
11:52 That an 8080 running the terminal? That's hilarious... The Z80 replaced the 8080 in mini computer systems because it required fewer support chips and only 5v... But the freakin terminal is controlled by an 8080
@@RetroHackShack One thing about the old stuff that we lost was the ability to actually understand all of it. That's no longer possible. There's too much today for any single individual to know it all. You can know a lot of it, or enough of it, but all of it? That's just not practical anymore. I'm not sure when we crossed that threshold but we're well beyond it now.
Great video! How does the RS232 loopback help print characters to the screen when typing? I can't figure out how that would work, I was too young when these computers were in use.
The loopbck simply sends back data being sent out of the terminal. When you type on a terminal the typed text doesn't get sent to the screen internally as it does on a PC - it goes out via the TX lines, and the computer would send it back via the RX lines on the serial connection, allowing you to see whats being typed. The loopback basically ties the TX and RX together, ensuring that anything that goes out the TX lines (from the keyboard) goes back in via the RX lines (to the display). If you have a PC with a serial port, and a terminal program (such as PuTTY or HyperTerminal) and an RS232 wiring block like the one used in the video, you can try this yourself to see how it works.
Well its good to see it boot up, even if there are still a few issues. As I am sure you've already found, those drives will probably benefit from being stripped down, cleaned and re-lubricated as drives decades younger suffer from dried up grease!
Boot address is E800...There is a rom on the disk controller at that address. Disks are hard sectored... in other words a BUNCH of sector punch outs...and a few bunched together for sector 1. (I wrote drivers for printers and the like back in the dark ages. NS Dos had a 256 byte region that you could fit the drivers into.... There is no built in monitor...so you have to boot a floopy to get anything...
so did you just leave the screen gasket at the end or rebuild it? Always interesting hardware and stuff in your videos, really like it. Lot's of practical tips and even some history as well ;) Keep up the good work!
One common problem with S-100 buss equipment is the failure of one or more voltage regulators that are present on each card. That's a common place for a short to develop. The buss voltages are unregulated, and the cards are more or less responsible for regulating what they use. For this purpose, regulators of the 78XX family were common.
Actually, MS bought SCP lock-stock-and-barrel. Also, CP/M would want you to either pull the system disk and then insert the disk to be formatted, or you could specify to format the disk in the B: drive.
Unless you've got an analog alignment disk, don't even attempt to align them, you'll just make the drives unusable. Chances are pretty high that the root cause of the disk problem is lack of lubrication in the head transport mechanism.
about 30 years ago I had a Basis 108 computer that ran either CPM or Apple Basic. it was a desktop, heavy and massive, wish I had held onto it, just because I code in basic and that would be all it would be good for, that I know of. didn't have any other software for it, and it did not have a Hard drive, that I remember at least. but I could still get blank 5 1/2 in, floppy disks back then. got alot of enjoyment out of coding on it.
Did the broken flyback bolt go through the middle of the winding?.. If so it's probably a good idea to fix it back in the hole with some silicon or hot snot or whatever.. it's part of the transformer tuning (actually critical). These have a habit of failing on 70's Trinitron TV's and invariably kill the flyback.
We had one of these in school with 4 screens and 4 keyboards. You had to write your programs to print to your terminal. 10 Input Q 20 Print#Q"Hello World" 30 Goto 20 You could have fun writing messages to the other screens with a for next loop then clearing them away. This and a Commodore Pet were my introduction to computers. Many Thanks to Mr. Todd who used to open the computer room up for me before school, I learned a lot and it changed my life.
Yeah. It does. I forgot to go into all the ICs on this thing when I was recording. Luckily it has a great service manual. I wish they were all like this. osiweb.org/manuals/hazeltine1500_maintenance.pdf
We used these in college along with a whole lab full of Commie Pets.... Had an Apple ][, a trash 80 and some other weird and wonderful machines..... IIRC the CP/M COBOL compiler would crash if you had a bug in your code....
Yeah, I prefer WD40 because it doesn't eat into plastics. You can leave it sitting and usually just wipe it afterwards. The smell is really nasty for some time though. On glas your method or acetone should do the trick since you would hardly hit any plastics. To finish I prefer spiritus based window cleaner (Frosh in Germany f.j.)
I did a side by side test a while back. The lighter fluid evaporates rather quickly, so the smell dissipates over a day or so. th-cam.com/video/O69z7UYxQ9o/w-d-xo.html
@@jayc2469 It's always a good plan to have a wide range of solvents available... not forgetting plain old water for anything suspected of being sugar based.
I believe it's pronounced Hazeltine. WD-30 is definitely better than WD-20, but I'd still go with WD-40. In all seriousness, that is a cool machine and I wish computers were still built as well. After watching DIY Perks I've been thinking of building a case entirely out of wood. Get some brass sheet metal, either walnut or mahogany.
Yes. It matters. Soft sectored disks have one hole in the media. Hard sectored disks have them all the way around the circumference of the media. You can't use soft sectored disks in systems that expect hard sectored disks.
Brings back memories of having multiple floppies between machines. Also CPM had so many different sector layouts. Ended up using serial linkup to transfer my programs. Until I got a pc XT and got some shareware software which was so good at transferring data on internal floppy. That was the first shareware I paid for as I used it in my job and thought it fair. The transfer data was to be used at home on my C128 with 1571 in the latter years.
Hard sector: index hole for start of track and then another for start of sector. Soft sector: just the one index hole for start of track. Super soft sector:. Apple did this just write a pattern on the track to indicate start of track and start of sector. Interleaving it either the data. Way too much trivia in this head.
I'd be afraid of high voltage. I'm used to my power supplies being in sealed boxes, and I personally don't mess around with CRTs. I'm sure you're doing everything safely, but we don't see you discharge the CRT on camera, so I'm left on edge about it possibly still being charged.
When you were taking the CRT out you held it by the neck… that’s a really good way to break the tube. You should always hold it by the body of the tube and be VERY careful to not hit the neck on anything - they are quite fragile, and essentially unubtainium now that nobody manufactures them anymore.
After the utter disappointment you suffered with the 70s Trinitron, it's so good to see (and share) your delight in getting this beautiful machine running.
Very well done. +1
Thanks. I record these things in real time, so even I don't know what the outcome will be until I get there 😜
I built my North Star Horizon in 1978 and used it for years. Eventually I updated the cpu, fdc, and RAM boards. I still have the system and have been trying to revive it
That's awesome!
I am currently trying to fix a Northstar Horizon that I acquired a year ago. I'm still struggling to get any output from it. I think I need to get one of those chip testers because I think something on the IO side of things is not working, or I do not have the correct boot disk. The lack of output from the system if no disk is found makes it hard to diagnose.
Not sure that was pure silicone. If it was, mineral spirits are your solvent. The problem with that is that it works so well you wind up smearing liquid silicone all over the place. I usually try to manually remove it if I can. Lighter fluid is Naptha, also available in larger volumes at your local paint store. Works a charm on stickers and adhesives in general and if worse comes to worse, pour some in your zippo and set it on fire.
Brilliant! There's a Hazeltine 1500 sitting on the shelf right next to me, waiting to be cleaned and restored. My unit has the anti glare screen coming of in pretty much the same way as yours. ;)
Maybe it's a common failure
The Hazeltine 1500 was one of the first low-cost smart terminals, from a company with a rather interesting history.
Most 5.25-inch floppy disk drives won't spin up without a control signal.
The memories. My high school had one of these terminals. It was connected to a computer that had a couple of 8" FDD and a card reader. It had stopped working. I fixed it by setting up the dip switches properly. Someone must have messed with them. It was a buzz for me as a 12yo to 'fix' such a big computer that no one else at the school could.
Nice!
Boy this takes me back. I was a cop in a small North Dakota city, the locals learned somehow that I was also a computer geek. Suddenly my phone would ring as I was trying to sleep, and my wonderful wife was working at the local nursing home, some business would be having computer troubles, this in the late 80's. I worked with C= machines but these folks were using early IBM, Epson's and such, so I learned how to work with CPM and DOS as well. Now my C=128 came with a version of CPM so I played with that to get to know the language, our city Judge had an Epson running CMP and he helped me get into it as well, he didn't know much about it except how to load his software but that bit helped. One fellow had a 10 MEG external Hard drive that was HUMONGUS and weighted a TON. He sold his machine to the Newspaper but the monitor was gone, so the paper owner had me go up in his store room and print out a database of all citizens and farms that the old business had gathered to use for his plat book. Man talk about a hot noisy job but I got it done, and as a reward the paper gave me the machine, after all he just purchased it for the data. Ah for the good old days when only we few knew how to work these mysterious magic boxes!
Great story. Thanks for sharing!
I recently acquired a keyboard module from a North Star Advantage. The key caps are gorgeous. They are the favorite of all I own. It's foam and foil, though, which isn't everyone's cup of tea.
Nice!
A paperclip is usually the correct size to fit in db25 and de9 ports
That’s a big milestone. Well done mate.
Thank you, sir!
The yoke looks to be slightly twisted after the reassembly. Just type a full line of text and twist it to get the text perfectly level.
I used this system connected to a hard disk while I was at college learning how to program in cpm.
I can remember fixing one as it blew its tantalum capacitors.
If I owned it I would add crowbars to power supply rail's.
Crowbars ? I don't get it.
@@cairsahrstjoseph996 crowbars is a description of a circuit. Which normally consists of a Zener diode triggering a SCR across the PSU rails as though you was throwing a crowbar in to stop a machine. It is to protect all electronics downstream and to blow the fuse if the power supply was to supply more than say 5V. I have installed them in my Commodores and other vintage machines to protect them. Switching supplies usually fail safe but linear PSU don't.
@@Electronics-Rocks Thanks! I thought it was a joke of some kind :) Sounds very useful for keeping these old machines running.
@@cairsahrstjoseph996 I see you have the commodore logo so what do you do about your PSU as CBM not that reliable.
Back in the 80's had a report of a machine running hot only to find over voltages. Any problems thou shalt test voltages first!
@@Electronics-Rocks I gave all my Commodores to TPUG some time ago; but, back then (2000's) I never had an original brick PSU bust a machine, although a couple of times I had a PSU fail during operation (guess I got lucky); and I didn't have voltage testing apparatus either. Never had a 64 simply fail during operation, either (more and more lucky!).
When the Hazeltine 1500 was market current, about the time I was attending University of South Florida in Tampa FL, it was very common for terminals to be positioned in rooms with anti-static flooring and pretty intense air-filtration. By the time personal computers like the Apple II and IBM AT were starting to edge out mainframes, you started seeing a more lackadaisical placement of computer hardware and the grime inside the case could get to fire hazard levels. In the mid-1980s, at Marshall University in Huntington WV, I saw quite a few Hazeltine terminals that were hooked up to the university's VAX mainframe and they were all approaching end-of-life from hard use and poor (if any) maintenance.
Over the years, I've seen melting of the sealant on old CRTs and terminals pretty often. Something in the chemical composition of the sealant causes it to go all tarry after about 20 years, well past the expected lifetime of the hardware. A good deal sooner if the component has been stored in a situation without rigorous climate control like the manufacturer expected "back in the day".
I don't know if Northstar ever had compilers for PL/I, Cobol, Fortran, Basic, and Pascal, but I do clearly remember doing an ungodly amount of coding in PL/I, Cobol, Fortran, Basic, and Pascal on Hazeltine terminals. :D.
That's pretty good that you have a working system, and terminal, with relatively little work needed. Very nice.
For sure
Excellent video. I was expecting at least one Tantalum cap to pop though! N* used some particularly explody ones on their boards :)
If you have no luck after cleaning the drives try checking/swapping the LF356 Op-Amp in the top left of the disk controller board. I've had to swap these on three of my MDS-AD3 boards after they showed very similar symptoms as yours.
Me too
We had one in the local library. You could book time on it or the MIcroBee. Dearly wish I could find one for my collection. Love this.. they're not easy to find any more :)
I did my computer college course on this baby, loved it. A Microline 83 Printer was connected. Had a Microtan 65 at home. Loved the early days of computing.
Awesome
Great Video! especially enjoyed seeing the Terminal/Monitor restored
Thanks!
Definitely want to see more from this computer, hope you can get those drives fixed.
Me too
Good Grief; that capacitor is the size of a can of soup! The only ones that I can think of are bigger are the ones in Tech Tangent's Data General and the ones in early television sets, which were like shoeboxes.
I can hardly fathom these enormous capacitors, amusingly in a microcomputer
Yeah. Don't see them much anymore. I thought the ones in my Apple 1 we're big. These are huge.
Great video. Love those vintage PCs. Thank you
Captive screws, or bolts, would have increased the likelihood of this model being able to compete for contracts for equipping ships or air crafts.
The terminal looks really nice.
I feel really good, watching this on a Sunday morning, eating toast, drinking coffee while also hanging up my laundry.
CP/M wasn't a clone of DEC RT-11, but it certainly drew inspiration from it. And RT-11 was influenced by earlier DEC operating systems for the PDP-8 and DEC-10. Windows use of forward slashes for command line switches and CR/LF line separators for text files can trace their lineage through MSDOS and CP/M back to DEC.
Cool. Thanks for the info. It might be interesting to do a trace of this through history.
This thing reminds me of an old Heathkit H89 computer I picked up at a church garage sale years ago. It also used hard-sectored disks, and it could boot both CP/M and HDOS as its OS. A special latching key on the keyboard would essentially disable the CPU and let it act as a dumb terminal. I wish I still had it, it'd be worth a fortune now.
Darn. Another system to add to my wish list 😄
Beautiful minicomputer! Very jelly.
For color CRT the anode is 27kV typical and for the monochrome CRT the anode should be 15kV as far as I can remember.
Sounds about right.
That's a beautiful terminal.
exciting! i like the simple mechanical fix for that transformer
32:55 DQ, aside from being tasty, is probably "dual quad" disk drives, quad capacity being North Star's term for double sided/double density. On their later Advantage machine, the CP/M herald would show 2Q or HQ depending if it was a hard disk system, for example.
Cool. I did see that at times when I was messing with CP/M.
Great video! I think we need more on these systems that happened right at the beginning. I would love to get one of those terminals and just plug a Pi into it and simulate a PDP11 or something. 😁
Same here. I might do a video on that. There are some good projects around for this very idea.
Hercules is your friend for RPi "Big Iron" rigs. My Pi Zero2W thinks it's a 360. The physical size comparison is comedy gold.
sticky is the heat degradation from humidity the cold issue can also be ram if its below 62F
Another good goop remover is VM&P naptha, which is very similar to lighter fluid.
Thanks for the tip
It's an interesting mix. 70s electronics, 80s aesthetics, 90s (simulated) tracker music. I dig it.
Thanks! I like to cover all the bases ☺️
11:52 That an 8080 running the terminal? That's hilarious...
The Z80 replaced the 8080 in mini computer systems because it required fewer support chips and only 5v...
But the freakin terminal is controlled by an 8080
Really nice vintage machine you got there.
Thanks
Seeing this makes me appreciate what we have now more.
For sure. We take a lot for granted these days.
@@RetroHackShack One thing about the old stuff that we lost was the ability to actually understand all of it. That's no longer possible. There's too much today for any single individual to know it all. You can know a lot of it, or enough of it, but all of it? That's just not practical anymore. I'm not sure when we crossed that threshold but we're well beyond it now.
Great video! How does the RS232 loopback help print characters to the screen when typing? I can't figure out how that would work, I was too young when these computers were in use.
The loopbck simply sends back data being sent out of the terminal. When you type on a terminal the typed text doesn't get sent to the screen internally as it does on a PC - it goes out via the TX lines, and the computer would send it back via the RX lines on the serial connection, allowing you to see whats being typed. The loopback basically ties the TX and RX together, ensuring that anything that goes out the TX lines (from the keyboard) goes back in via the RX lines (to the display). If you have a PC with a serial port, and a terminal program (such as PuTTY or HyperTerminal) and an RS232 wiring block like the one used in the video, you can try this yourself to see how it works.
You either run regular DOS or extra crispy DOS.
LOL
Well its good to see it boot up, even if there are still a few issues. As I am sure you've already found, those drives will probably benefit from being stripped down, cleaned and re-lubricated as drives decades younger suffer from dried up grease!
Yup
Boot address is E800...There is a rom on the disk controller at that address. Disks are hard sectored... in other words a BUNCH of sector punch outs...and a few bunched together for sector 1. (I wrote drivers for printers and the like back in the dark ages. NS Dos had a 256 byte region that you could fit the drivers into.... There is no built in monitor...so you have to boot a floopy to get anything...
I had a singe density drive system and double density drive system.
I remember that computer and the S100 bus.
Great progress!
Thanks
I remember my brother using a Commodore Pet to do some real computing, not only playing games or writing endless loops in BASIC.
Nice
so did you just leave the screen gasket at the end or rebuild it?
Always interesting hardware and stuff in your videos, really like it.
Lot's of practical tips and even some history as well ;)
Keep up the good work!
I just left the gasket out.
Dude! Like the guy who is Arctic Retro is your flipping TWIN.
I need to check out his channel
One common problem with S-100 buss equipment is the failure of one or more voltage regulators that are present on each card. That's a common place for a short to develop. The buss voltages are unregulated, and the cards are more or less responsible for regulating what they use. For this purpose, regulators of the 78XX family were common.
After repairing a couple of these I would suggest to add some power supply crowbars.
Thanks for the suggestion
Actually, MS bought SCP lock-stock-and-barrel. Also, CP/M would want you to either pull the system disk and then insert the disk to be formatted, or you could specify to format the disk in the B: drive.
Microsoft bought the SCP corporation
Unless you've got an analog alignment disk, don't even attempt to align them, you'll just make the drives unusable. Chances are pretty high that the root cause of the disk problem is lack of lubrication in the head transport mechanism.
That is what I am hoping for
First computer I ever used! Hadn't a clue and reformatted the hard drive and turned in into a brick!
Oh no!
about 30 years ago I had a Basis 108 computer that ran either CPM or Apple Basic.
it was a desktop, heavy and massive, wish I had held onto it, just because I code in basic
and that would be all it would be good for, that I know of. didn't have any other software for it, and it did not have a Hard drive, that I remember at least. but I could still get blank 5 1/2 in, floppy disks back then. got alot of enjoyment out of coding on it.
Someone using lighter fuel for cleanin. Instant thumbs up!
But can it tell me the 11 herbs and spices 🤔
Only if I can get the floppy drives working 😂
Did the broken flyback bolt go through the middle of the winding?.. If so it's probably a good idea to fix it back in the hole with some silicon or hot snot or whatever.. it's part of the transformer tuning (actually critical). These have a habit of failing on 70's Trinitron TV's and invariably kill the flyback.
It was the other end actually. Not the end with the gap.
What happened to the disk drive repair video?
Yes. Thanks for reminding me. I need to come back to that and talk more about conversion and indexing.
The HORIZON was my dream computer in the day… but then I went to work for DEC !
Ha
FYI, the C-64 & Apple II didn't use the index hole at all.
Now i am imagining that someone theew their laptop in to the kfc frier
Lol
Hit ^g on loopback and you should be able to make that speaker sound. (Ctrl-g is ASCII 7, or “bell”)
Good to know 👍
Oh wow T-Slim, what canullas do you use?
First DOS for microcomputers. You could store 90 Kbytes on one single diskette.
All that effort to do a loopback test. Back when I was repairing dumb terminals, a paperclip was often the preferred tool for loopback testing!
For sure. I think there are voltages on that serial port so I wanted to play it safe and show others that struggle with pinouts like me 🙂
We used Hazeltine 1500 in the computer lab when I was in school. I have heard it pronounced both ways, but I am pretty sure that it is 'Hazel teen'
Thanks
We pronounced it "Hazel-tin", so I guess there are (3) ways you could say it. "Tine", "Teen", or "Tin".
@@craigjensen6853 I had never heard that way, but it does make sense. Three ways it is
i hear wd-40 is stronger than wd-30
LOL my brain just doesn't work right sometimes. I didn't even know I said that until I was editing.
We had one of these in school with 4 screens and 4 keyboards. You had to write your programs to print to your terminal.
10 Input Q
20 Print#Q"Hello World"
30 Goto 20
You could have fun writing messages to the other screens with a for next loop then clearing them away.
This and a Commodore Pet were my introduction to computers.
Many Thanks to Mr. Todd who used to open the computer room up for me before school, I learned a lot and it changed my life.
Very cool. Thanks for sharing that.
Those old computers surely were well-built.
For sure
I learned two new things from you today about computers. After 40 years. Thanks. DQ, F KFC.
Awesome. That is half the fun.
I'm going with "teen" over "tine" like Ovaltine, solid guess. ^_^
very good video
Thanks
@@RetroHackShack your welcome
This terminal has a separate processor - Intel P8080. Or did I see badly?
Yeah. It does. I forgot to go into all the ICs on this thing when I was recording. Luckily it has a great service manual. I wish they were all like this. osiweb.org/manuals/hazeltine1500_maintenance.pdf
We used these in college along with a whole lab full of Commie Pets.... Had an Apple ][, a trash 80 and some other weird and wonderful machines..... IIRC the CP/M COBOL compiler would crash if you had a bug in your code....
Great memories!
But will it run Cyberpunk 2077 or RDR 2 ?
Yeah, I prefer WD40 because it doesn't eat into plastics. You can leave it sitting and usually just wipe it afterwards. The smell is really nasty for some time though. On glas your method or acetone should do the trick since you would hardly hit any plastics. To finish I prefer spiritus based window cleaner (Frosh in Germany f.j.)
Seems RHS’s method worked fine.
I did a side by side test a while back. The lighter fluid evaporates rather quickly, so the smell dissipates over a day or so. th-cam.com/video/O69z7UYxQ9o/w-d-xo.html
that one is probably around 11 to 16 Kv
MS DOS was originally IBM PC DOS. But for whatever reason(s) IBM chose to sell it to Microsoft.
No it wasn't
More Questions About S-100 Computers ?
www.s100computers.com
led is probably 3.3v
2V actually, but it is being fed by the 5V rail.
Dynamic file allocation? Bah! Hard sector floppies, baby and you knew where every byte was.
-grizzled old Northstar Horizon owner.
Ha. I need to do a follow on this one soon. Those drives need some TLC.
I know there's a KFC that made monitors back in the day. Sadly, not this era AFAICT-VGA monitors, not terminals.
Interesting
CRT monitor look even better if you use a polkarizing screen cover
Amazing and sad that someone would send this to ewaste in the first place. Glad it's in good hands.
Being the KFC computer, DQ surely means Dairy Queen.
Ha ha. I thought is should, too.
Acetone also works
Yeah. That's my last resort.
@@RetroHackShack I get you. Acetone can be fairly destructive to some plastics
@@jayc2469 It's always a good plan to have a wide range of solvents available... not forgetting plain old water for anything suspected of being sugar based.
Love the content, but I can't hear you properly over the music.
I believe it's pronounced Hazeltine. WD-30 is definitely better than WD-20, but I'd still go with WD-40. In all seriousness, that is a cool machine and I wish computers were still built as well. After watching DIY Perks I've been thinking of building a case entirely out of wood. Get some brass sheet metal, either walnut or mahogany.
That case sounds sexy! I have seen lots of custom keyboards with wood cases over the past few years, too.
Captive screws ❤❤❤❤
Maybe try WD-40, this WD-30 seems like a cheaper knockoff =P (Joking of course)
all 5..25 inch disks have the index hole... it's there to tell the drive where sector zero is... whether it's hard or soft sectored doesnt matter :D
Yes. It matters. Soft sectored disks have one hole in the media. Hard sectored disks have them all the way around the circumference of the media. You can't use soft sectored disks in systems that expect hard sectored disks.
Brings back memories of having multiple floppies between machines. Also CPM had so many different sector layouts. Ended up using serial linkup to transfer my programs. Until I got a pc XT and got some shareware software which was so good at transferring data on internal floppy. That was the first shareware I paid for as I used it in my job and thought it fair. The transfer data was to be used at home on my C128 with 1571 in the latter years.
Nice
Hard sector: index hole for start of track and then another for start of sector.
Soft sector: just the one index hole for start of track.
Super soft sector:. Apple did this just write a pattern on the track to indicate start of track and start of sector. Interleaving it either the data.
Way too much trivia in this head.
Woodgrain 🤤🤤🤤
Mmmmmmmm woodgrain
Everytime you wave your hand around the computer's power supply or the terminal's CRT, I can't help but physically cringe.
Why
I'd be afraid of high voltage. I'm used to my power supplies being in sealed boxes, and I personally don't mess around with CRTs. I'm sure you're doing everything safely, but we don't see you discharge the CRT on camera, so I'm left on edge about it possibly still being charged.
I was pretty scared the first time I worked on a CRT. Now that I know what I am doing it's not so bad.