The 63.5 watt power supply in the original PC can generally handle a half-height hard drive, but not the power-hungry full-height drives that were the only kind available when people first started installing them into their PCs and caused them to burn out their power supply. Aftermarket power supplies with higher output didn't become readily available until half-height drives had already become common. But I think some of the later 5150 PCs came with the same 130-watt power supply as the XT.
I once had a 5150 with a 63 watt power supply and a 10MB full-height hard drive. It would only turn on for half a second before the power supply cut out. I ran the drive off another power supply and everything worked fine.
I actually used to use some old computer power supplies out of machines of probably around this time for some things. back when it was not as popular to repurpose computer power supplies! Everything in the machines works except they were just obsoleted buy new equipment. and they said all you have to do is say yes I want them. of course took advantage of anything I could Salvage. They were a mix of generate the different generations of the IBM machines . and yes some of them did have something similar to that as nexternal power supply. although some literally had a power supply for a computer installed in a external chassis that was just a power supply and power connector an output connector. The weird thing is it turns out those were full-size power supplies. Don't remember any of the ratings on any of these either but they were about the same size as the original. with a power supply that was external. Also there was a small box that was used on some these machines I received. I do believe it was some of them with the external power supplies? which would make sense it was a box that had power switch on the front if I'm not mistaken the IEC inlets and Outlet connectors including one for monitor which also had a separate switch. which makes you think these machines were left on 24/7 having a separate switched receptacle for monitor. But the power switch for that little box the main power switch turned off all Monitor and two or more additional IEC power receptacles. there might have been one perhaps that would stand on and there was also one standard receptacle as well which is just odd. I have no clue what these machines were originally used for either! But it was an oddball application. And there were also similar switch boxes except only for Monitor and computer power only. As well as often there was a note on there on some of those switch boxes... that said not to turn off the switch on the computer and turn off the monitor. and not the MainPower the power switch off unless instructed to. It was a marker on masking tape labels! Said something about when not using computer leave running but turn off. monitor switch but not on every one of them ! strange set up to say the least. Although in school we were supposed to actually use the power strip switch and not the switch on the computers! all the instructors we're told to let the students know this because evidently there might have been a reliability at issue???? and apparently they had to have work done just because of the switches on the computers failing??? in normal day-to-day use! But I don't know if that was an actual issue or if that was hearsay that just caught on. Also they did not call them power strips they called them Gator strips!
Shugart Associates Systems Interface or SASI was developed in 1981. 5 years later in 1986 It was then evolved into ANSI SCSI which was later on renamed to SCSI. SASI was used mainly in mini and micro computers in 1981 until 1986 when it was then evolved into ANSI SCSI
In the first couple of releases of PC Magazine (1982, pre-XT), there are adverts for some SixPack Alike Cards, including an SASI, not SCSI, SASI Controller. Apparently this was once a common method to get big 8" tapes and Winchester drives connected to your new IBM Micro Computer. And I recently learned that though SCSI evolved out of SASI, it's not really backwards compatible. Well at least physical it is and theoretically too, but the command set varies between these two slightly. That is that SASI does not have an INQURY command. And it's giving me a headache with my Shugart SA-1004 drive and SA-1403 controller. Because without an Inqury Command, it can't be really detected by the SCSI Controller Software.
@@lucasrem I recall having to work with 8-bit and 16-bit IDE drive differences, the ST-506 interface, and a sort of precursor to IDE drives in the Compaq Portable II where it had an extra card on the drive itself. So many years ago... ☺
@@Tombowolf that is how a bunch of things are they evolve and improve from an older standard but are not compatible. There are many reasons why that can be
I had an old IBM AT had that little power supply. It's rated for 40watts and was used to power a Floppy Drive and Colorado Tape drive. I reused it when I swapped the motherboard out for a Socket3 486. Used it to power the Hard Drive, Floppy and CD-ROM.
That TEAC tape drive deserves a dedicated video very much. You would need a data cassette, like TEAC CT-600 or Maxell DC-300 (ones with notch on the top). My guess, than notch indicates that tape drive won't take a regular compact cassette (?)
I’m almost certain that TEAC drive uses the standard audiocassette tapes. Would be a fun mini episode to get that drive up and running. What’s strange is that the drive seems to have a much more complicated mechanism than a traditional QIC drive from the era.
I agree, it sure does look like it. Found the manual for it on archive.org, but there is no mention about the sort of cassette tape it uses. Interesting in any case. In the maintenance manual there is a drawing of a cassette tape, but it has a weird notch in it. Not sure what they mean by that.
I have the same(maybe) TEAC tape drive in my collection and it DOES definitely uses normal audio cassettes. I have tried and it works fine with what is available today but it has to be blank for it to be able to be formatted for data storage use.
I'm familiar with these TEAC tapes as well. They sure looks like regular audio tapes but they are not. There are some tabs/holes that differ if I remember correctly that prevent the use of regular audio tapes. Maybe it's possible to convert a good quality audio cassette tape and see if it can be made to work. A video idea for Adrian maybe? :)
Part of the difference is the tape formulation, the magnetic coating. It's similar to the variations of audio cassettes, with basic original ones, chrome, ferrichrome, metal, listed as Type I, Type II, etc. I used a similar data cassette drive in the late '70s on a Perkin-Elmer minicomputer. A similar situation went on with 8-mm and later on 4-mm tapes, they had data tapes, and video tapes for camcorders. Trying to use 8-mm video tapes for data storage was hit or miss, leaning toward the miss side. We ended up fighting with a supplier who would send us video tapes when we ordered data type; I think we ended up switching suppliers.
I remember when I used these machines at GMC Vauxhall Bus and Truck in Luton UK and at a previous company's, IBM would refuse to fix there products if you had non IBM modifications. This may be why this mod was done so if it needed to be serviced or repaired, the machine would have to returned to it's original state. The parts were very expensive.
Especially if you consider that, according to what he mentioned a couple of times, he does not create RUclips content as his main job, it is just his hobby.
Argh, the slow memory check...I got bitten by that recently troubleshooting a PC with memory isses with no monitor attached. For ages I was thinking that the system was failing to POST, when in fact I just needed to wait a few minutes for the beep.
This is an aux PSU for the 5150 with it's 63w PSU. There was a round knock-out plug on the 5150 chassis rear panel that would fit this round connector. It's a neat and now pretty rare upgrade item. Neato!
I just got a 5150 that had a Seagate drive installed. The two half-height floppy drives were powered by that auxillary power supply. I don't have the aux PSU but the cable was in the case. Something from a bygone era. I don't see a use for the cable. If I wanted to provide adaquate power I'd replace the internal PSU.
Q&A + WP51 was ver common. FP is First Publisher (GUI loosley based on the the AtariST version). The mono card is probably also Hercules compatible, specifically for the HiRes software in mono.
I do remember at one time we did have Q&A installed on one of our computers years ago don't remember when it was pretty sure it was beyond Windows 3.1 but not sure
It was funny to read that the last modified dates were in 1995. I can only imagine someone using this seeing the shiny new Windows 95 release and needed to upgrade! :D
Swapping power supplies would've voided IBM warranty, especially if you were a company and had an IBM support contract. Having a separate power supply for the TEAC tape drive would've left the original 5150 hardware in place and operating independently from the Everex stuff. Also, tantalums popping are cake. I can remember working at Netscape in the late 90s and having a dev server decide to blow a few big electrolytic capacitors. Sounded like gunshots and caught the chassis on fire. After hosing it with the fire extinguisher and letting things cool off we took it apart and it had blown holes in the power supply circuit board and the motherboard, as well as putting a dent on the inside of the case.
The round connectors are Amphenol CPC series connectors, “Circular Plastic Connector”. They come in many sizes with lots of pin counts available, a cheap alternative to expensive mil-spec metal connectors.
@@adriansdigitalbasement2 What amazes me.. is that this decent software at 37:05.. is running on 640Kb of memory 😯.. and it must use 1Mb or 2Mb top's in the HDD 🤔............... something like this today.. waste 30Gb or 40Gb 🤢... requires like 16 CPU Cores and 20Gb of RAM at least 😤...
My first job as a computer engineer was repairing and aligning floppy disk drives. The IBM Tandon 5.25" 360k was the first drive I ever did. In my second job I worked on everything else you were looking at on that XT PC. We had a clean room where we rebuilt HDDs and the ST225 was certainly one I have worked on. Replacing heads, platters and writing the servo which I think was Cylinder 0 -1 or maybe -2 with a small servo track writer that you could manually move the heads with. Then we used a Hdd analyser to perform a complete surface test. Then attach the drive to the PC booting to DOS on a floppy, running debug with g=c800:5 to initiate the low level format utility in the controller's ROM. Then finally partition and hi-level format the HDD.
Just think about the "Centronics" parallel printer interface, or the "Hayes" modem AT command set. Plenty of company names used for products, often outlasted the companies themselves! I remember SASI drives, and SCSI coming out. Also the HPIB / GPIB / IEEE-488 instrument control bus, evolving from proprietary to a standard.
These XT's are great , this is Vintage IBM , These will be nice to Curate and Show as examples of PC's from this Year . Have some games , software and Documentation in plastic saved so you can sell each one when you need to , Great Video :) QC
The purpose of the "appendage" reminded me of mod I felt compelled to make in the early 2000's for my file server at home. As a poor college student, the most powerful power supply I could afford was a 300W ATX. At the time, I was running a Pentium II 400MHz in a full tower chassis with as many used old SCSI hard drives as I could snipe on eBay. At one point, the server had 10 SCSI HDDs (10K, 15K, etc.) and two IDE HDDs mounted and I was certain I couldn't reliably power everything from the single ATX supply. So I scavenged another 300W ATX supply and built a "remote trigger" out of a relay, a large capacitor, a diode to protect against back EMF and an LED. It was energized by the main supply and the relay "turned on" the second supply. Most of the drives were connected to the second supply, leaving the main system and IDE drives on the first supply and I ran in that configuration for years. Best. Space. Heater. Evar. ...also very noisy.
The IBM 5150 had a round punchout above the cassette and keyboard ports on the rear panel. That is likely where the round power connector was intended to be placed.
I once had a system that used a card with a complete PC W/Ram and was used as a network syste. You would attach a monochrome monitor to the card and it would use the PC resources for hard drive and data transfer. You could put up to 3 of the cards in a system in order to have a 4 terminal network with the PC being used as the server. This was around 1986, unfortunatelly, I cannot remember the name or brand of the card.
3:10 Oh, neat! My employer uses threaded circular connectors like that, albeit in a 37-pin flavour, in embedded systems. It's pretty trippy to see that sort of connector in a household or office machine from the 1980s. Incidentally, on our machines, it allows for a single uniform connector to be used for subdevices to be powered from or communicate through a bunch of different buses. Like, I have some subdevices where 6 or 8 particular pins are connected for specialized communications, and others where a different 4 or 5 are connected for power plus serial comms.
By the way there are versions of a similar connector I'm some sort that actually have pens that that can be used from full line voltage power and also low-voltage pins in the same connector that's scary stuff! I know that on some airport X-ray machines this is used for the monitors which is just the little bit dicey to the unwary. And you know how low voltage in line voltage should be separated although if suitably insulated for the voltage at hand and equivalent insulation it is permitted encode but I don't know if that goes for with connections like this I do know that that is 4 in conduit at least. And at a church where do we have a organ console that was on the long table where there was both power and of course low voltage the organ company refused to bundle the entire cable because of that it was a code violation to do so even though those connections were right next to each other all the time we later found out that the cabling that was used the insulation was suitable to allow this to be done. Most electrical tape I've ever used on one cable! We look forward alternative but yeah won out in the end with just roll after roll of black tape! I've also heard that they used to use fire hoses for these flexible umbilicals I'd called them on installation Pro is both ends were hardwired so there was no way to slip anything over it after it was installed. They specifically did not use connectors because of reliability. Plus there would have to be numerous connectors since there was hundreds wires coming in from the organ console it was actually telephone cable that was being used! The AC power was a separate cable not to mention a low voltage cable I do believe that might have just been the common for low-voltage! Although in the organ itself everything was not insulated what one might think. Since everything was at mostly the same polarity that wasn't necessary. If there was a short somewhere it would just malfunction. It was rare to have a short between the common wire and anything else! Wrangling that cable when the console was moved was like wrestling an anaconda you could say
Also I have seen a similar connector often on a junction box cover. typically in retail stores here and there just in random places. I'm wondering what those were used for originally possibly! And I know those connectors were used on some cash register systems. I did Salvage a few but having them not just at the piece of equipment the between peripheral is just odd.
The cable hanging out of the side reminds me of my A1200 setup in the 1990s. Which consisted of an A1200, with 2.5-3.5" IDE converter ribbon which trailed out of the Amiga case into an empty (except for PSU, 3.5"HDD and CDROM) PC/AT case. Quite a fragile system.
for things that plug directly into mains I made myself a little box that contains a GFCI and a paddle lightswitch so if shit starts to hit the fan I can slap the switch if the GFCI doesnt catch it ... its only tripped like 3 times in the last 10 years but it is nice to have a quick poweroff when the smoke starts coming out without having to touch the device in question. Of course its not the ideal way to do mains testing on mains powered devices but its one step better than hoping that you can yank the cord out of the flaming ball of angry sounds and can be cobbled together for a couple bucks at the hardware store
My father's PC had a similar problem where it would halt after about 1.5 hours of use, turned out that the lower address latch was faulty (the 8088/86 multiplexed the data bus onto the address bus, so these latches were needed)
At the moment my smallest room is filled with tech stuff waiting for cleaning, repair if needed and to be sold. I'm waiting for someone to move out finally so I have more space and time, but most importantly to be in the mood to do this kind of work. But right now I think that small room would give the impression that I'm a hoarder as well... :( I don't want to be seen as a hoarder!
I hear ya on bad 90's power supplies. So many were junk. PC Power & Cooling was my go to back then. SO good. Now it's Seasonic. They go in all of my systems. Thanks again for another great video. Fun seeing the workarounds that they had back then.
It's been a minute since I've heard someone say the name Everex, I had a few of their laptops before they went out of business, and they where some of the worst I've ever owned having the VIA C7 X86 CPU's in them, as the Windows drivers barely worked, and Linux on them at the time was a true pain, plus overall just being slow as molasses to use. So I'm not surprised the little Everex PSU you had on this machine was crap.
Yes the rectangle on the back panel was the batter pack for the CMOS, a lot of them were removed due to the barrel or other battery spilling its badness on to the board, I had a like model Zenith Data systems desktop. Came from a government office had a network card for a sat network that got struck by lightning
There are all kinds of Everex prototype boards floating around... tho unforutnately I missed all the ones that were from our old office. Everex had some of the first 16 bit and 32 bit display boards that were affordable and any good. Then they had the first 16+32 bit color VGA boards. Their catalogs were pretty boring I don't know why they had such cool stuff like oscillator boards when they didn't seem to have anywhere to sell them! ANyway lots of prototype boards to look for. They sold lots of tape drives and memory cards and drive interfaces. They also made some of the best 286 and 386 computers available. I could tell you other secrets of Everex but am still looking for stuff! So that will have to wait.
That round connector looks like what is commonly called a “cannon” plug. They are pretty robust and designed for relatively easy repair if you have the proper (expensive!) tools, the military uses them as does Boeing - not sure if their competition does, but they are a din-standard connector
I suspect it's a TE Connectivity / AMP CPC connector; they are not the same a military type connector (602 or 62 style), althought the latching mechanism is very similar.
40 / 5000 From the Netherlands, a BIG thumbs up! I remember those machines and bringing them back to life is more than awesome!!! I Never expected to see that 'A:\' prompt anymore.
The 4-pin hanging connectors -- Circular Plastic Connectors (CPC) are made by AMP. This is the small cell size version using crimp type pins, compatible with 24 to 20 AWG wire.
Don't you just love a Tantalum tantrum? Thanks for another interesting video, Adrian and also for encouraging fellow Retromancers to get our Nostalgia high more cheaply!
Used to see ALOT of odd stuff added to PC's in the 90's while working for HP in the Detroit area. Especially around the auto industry, car repair shops, parts manufacturers, and factory floors. Good times when a 'special' one of a kind card or 'box' blew mother boards...almost impossible to fix sometimes.
I used to work on these giant magnet sector mass specs controlled with a specialized PCI card that costed 30,000 dollars. I accidentally blew one up because I thought the PC was powered off when it wasn't. Whoops.
@@ax14pz107 Right, as a tech you would drive 2 hours for an on-site service call to some factory in Flint, Michigan. The PC would be hooked up to some CNC machine and had a bad mother board. An hour of getting the greasy PC open and the mother board replaced. Of course the PC would be tested without all the 'cards' and it would boot fine. Put the cards back in and power on and the blue magic smoke would appear.
One thing that facinates me is that these computers have not been used for decades and still today they work, they may have a few faults (most of the time), but they still work. I really doubt that a modern PC would be still working in 20 years time. Old PCs are built like tanks and weigh as much, new ones all look nice with its RGB crud and whatever but they are made like disposable items.
Not only was this not used in decades, it was left uncovered in a hostile place (a hot / cold attic) -- so wasn't even kept in the best place. It is amazing how resilient this stuff is ..... I do wonder about modern stuff, but I do tend to think that at least the things without batteries should still be working in 30 years. Maybe? LOL
The hot/cold attic has good points, too. It may get to temperature extremes, but it gets there and stays there for a while, so it's storage temperature and not operating temps. Plus it seems to have been dry, no major moisture buildup or corrosion from if it had been. I'm not saying it was the best place to store it, just that there are a heck of a lot that'd be much worse! ☺
My sister-in-law used PFS:First Choice back in the day, it was a rough equivalent to others suites like Microsoft Works or Tandy Deskmate, or later more expensive ones like Lotus SmartSuite or Microsoft Office. It had word processor, spreadsheet, database and more. Not bad at all, especially on machines that weren't top of the line. Wow, just remembered MultiMate, and the set of programs called ChartMaster, DiagramMaster, and SignMaster. Easily about 30 years since I last used them. Or IBM's DisplayWrite 3 and 4 word processor programs, that stored the text internally in EBCDIC instead of ASCII.
I look forward to seeing you troubleshoot & repair the failed motherboard (because I have 2-3 old IBM PCs waiting their turn). I'm surprised that you didn't have the needed cassette tape(s) to test that portion of the system, especially since you had a complete diskette cleaning diskette "kit." Hopefully you will go ahead and test/troubleshoot/repair the cassette drive unit and show it working on one of these PCs.
It was probably an aftermarket kit. So, the power supply was supplied so it could be used on a wider range of PCs. As PCs were in their infancy. You ordered a PC with options provided by the manufacturer. IBM being a prestigious name at the time probably wanted a very premium price and the aftermarket solution provided more cost effectiveness to the customer. That part would have been added by the customer or the dealer. After market solutions were most likely installed by a PC dealer. It would go well with my Epson LQ-2180 which, I still use with Windows 10.
Used to use that publisher software on a Mitac XT clone belonging to my parent's business. Can remember the C:/pub directory. The GUI seemed pretty advanced to me at the time.
I thought it was the RAM because of the stack error too, but then you went and said it in the video so I won’t seem so clever for having thought of it :) here’s to feeding the algorithm
Im enjoying the 2nd channel stuff keep it up. its more like what you did before COVID and the Mail call stuff with the bags of sweets on the main channel
Everex made some of the fastest x86 systems on the market at the time. And their equipment was grade "A" quality. As for SASI, that stood for "Shugart Associates System Interface", and was the predecessor to SCSI. Wikipedia says: "ANSI developed the specification as "SASI" and "Shugart Associates System Interface"[7] however, the committee documenting the standard would not allow it to be named after a company. Almost a full day was devoted to agreeing to name the standard "Small Computer System Interface", which Boucher intended to be pronounced "sexy", but ENDL's[8] Dal Allan pronounced the new acronym as "scuzzy" and that stuck."
That's the first time that I'm seeing something that definitely looks like it's designed for the round hole of a 5150. Interesting discovery! As for that tape drive: Regular audio tapes definitely will not work. You need special cassettes that have special tape and a notch that tells the drive it's a legit tape (and that notch will also keep you from inserting the cassette bottom side up). By the way I have a batch file somewhere that I once made for FastBack, that will run it in DEBUG and will use breakpoints and go-commands to skip over the code that detects whether you have the original FastBack program disk in the drive...
That matches my experiences with them at an electronics manufacturer while testing boards and assemblies. Tantalum caps in backwards were a problem, too. My favorites were the ones that leaked a little silver teardrop when they failed. 😭
Remember, Adrian, the way to get more views and likes on YT is to make something go pop! Well, you somewhat succeeded; let’s see if we can take out any more caps, eh?
@@paulstubbs7678 yeah they actually call that power blasting also good for finding other shorted components although once there was something shorted on the board that was not a component and well there's a fine Trace put this way nice smell of extra crispy circuit board! And one capacitor or two going pop once that short opened due to that Trace becoming open circuit happn hooking up I didn't realize what had happened! Pretty sure that Trace opened and then to Cap's poped. Those Line Filter capacitors on some of the old equipment are the worst when they go. That are typically used in line filter applications. and some others the ones that are amber transparent color. Had one of those puppies go off on workbench once! I was doing some repairs on old piece of gear for somebody. Remember somebody ran downstairs and said what just happened and they just about got sick! And once I found out about what happened you better bet anytime that I got in a piece of equipment that had those! there was some pre repair work before even starting. at least after I knew what the issue was and the device was not repairable!
As far as the system failing the way it did, I'd check the memory. First check the 5V rail to make sure you have no shorts pulling it down. Since it isn't showing any video I'd start with the parity bit on bank 0 then move on to the rest of bank 0. Also check the ROMs. One thing is for sure, a Bank 0 parity fault will stop the machine from POSTing and there will be no beep codes.
When the IBM PC came out I have a feeling IBM was thinking well people will just come to us for all their upgrade needs, and we will make them to run off this PSU, and they will never need anything more. Boy where they wrong, just like how they bet the farm on Micro Channel Architecture. Don't get me wrong, as I love IBM design from back in the day like their Thinkpad laptops, ThinkCenture desktops, and keyboards(I still use an IBM KB-8923 on my work PC with an active PS/2 to USB converter) but man at times they trully did make some stubborn boneheaded decisions.
I figured that C:\PUB was some desktop publisher. I used to use First Publisher on my Tandy 1000A (and they later released a DeskMate 3 version) and now that I think back on it I think C:\PUB was it's default install directory.
SASI - Shugart Associates System Interface Was eventually extended to become SCSI-1 but ANSI refused to standardise it with a company name in the title.
Stack error sounded like the 0 page of memory died and may explain no POST, it probably either uses that memory during it or halts if it detects any bad memory in that page
Looks to me the external power supply is just a standard switching power supply shoehorned into a custom case. Could be why the bulge in the perforated cover. On the pc board markings, I believe the 94V-0 portion is the UL flammability rating or some such. Another way of checking for polarity markings might be to look at the pads and/or the solder mask around same… one is likely to be square.
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I'm changing my name to Scribblemonger Throckmorton immediately.
That name was used in the demo address book stack included with HyperCard on classic Macs.
The 63.5 watt power supply in the original PC can generally handle a half-height hard drive, but not the power-hungry full-height drives that were the only kind available when people first started installing them into their PCs and caused them to burn out their power supply. Aftermarket power supplies with higher output didn't become readily available until half-height drives had already become common. But I think some of the later 5150 PCs came with the same 130-watt power supply as the XT.
I once had a 5150 with a 63 watt power supply and a 10MB full-height hard drive. It would only turn on for half a second before the power supply cut out. I ran the drive off another power supply and everything worked fine.
I actually used to use some old computer power supplies out of machines of probably around this time for some things.
back when it was not as popular to repurpose computer power supplies!
Everything in the machines works except they were just obsoleted buy new equipment.
and they said all you have to do is say yes I want them.
of course took advantage of anything I could Salvage.
They were a mix of generate the different generations of the IBM machines .
and yes some of them did have something similar to that as nexternal power supply.
although some literally had a power supply for a computer installed in a external chassis that was just a power supply and power connector an output connector.
The weird thing is it turns out those were full-size power supplies.
Don't remember any of the ratings on any of these either but they were about the same size as the original.
with a power supply that was external.
Also there was a small box that was used on some these machines I received.
I do believe it was some of them with the external power supplies?
which would make sense it was a box that had power switch on the front if I'm not mistaken the IEC inlets and Outlet connectors including one for monitor
which also had a separate switch.
which makes you think these machines were left on 24/7 having a separate switched receptacle for monitor.
But the power switch for that little box the main power switch turned off all Monitor and two or more additional IEC power receptacles.
there might have been one perhaps that would stand on and there was also one standard receptacle as well which is just odd.
I have no clue what these machines were originally used for either!
But it was an oddball application.
And there were also similar switch boxes except only for Monitor and computer power only.
As well as often there was a note on there on some of those switch boxes...
that said not to turn off the switch on the computer and turn off the monitor.
and not the MainPower the power switch off unless instructed to.
It was a marker on masking tape labels!
Said something about when not using computer leave running but turn off.
monitor switch but not on every one of them !
strange set up to say the least.
Although in school we were supposed to actually use the power strip switch and not the switch on the computers!
all the instructors we're told to let the students know this because evidently there might have been a reliability at issue????
and apparently they had to have work done just because of the switches on the computers failing???
in normal day-to-day use!
But I don't know if that was an actual issue or if that was hearsay that just caught on.
Also they did not call them power strips they called them Gator strips!
@@aaronbrandenburg2441 What happen? Somebody set us up the concrete poetry?
Take off every ZIG! For great justice!
This reminds me of the old days when you'd get a used computer or hard drive and half the fun was seeing what files were there.
Shugart Associates Systems Interface or SASI was developed in 1981. 5 years later in 1986 It was then evolved into ANSI SCSI which was later on renamed to SCSI. SASI was used mainly in mini and micro computers in 1981 until 1986 when it was then evolved into ANSI SCSI
In the first couple of releases of PC Magazine (1982, pre-XT), there are adverts for some SixPack Alike Cards, including an SASI, not SCSI, SASI Controller.
Apparently this was once a common method to get big 8" tapes and Winchester drives connected to your new IBM Micro Computer.
And I recently learned that though SCSI evolved out of SASI, it's not really backwards compatible. Well at least physical it is and theoretically too, but the command set varies between these two slightly. That is that SASI does not have an INQURY command.
And it's giving me a headache with my Shugart SA-1004 drive and SA-1403 controller. Because without an Inqury Command, it can't be really detected by the SCSI Controller Software.
Enhanced Small Disk Interface, ESDI.
later systems got multi disk controllers, SCSI and IDE
Thanks, you saved me the trouble of explaining what SASI meant! 😉
@@lucasrem I recall having to work with 8-bit and 16-bit IDE drive differences, the ST-506 interface, and a sort of precursor to IDE drives in the Compaq Portable II where it had an extra card on the drive itself. So many years ago... ☺
@@Tombowolf that is how a bunch of things are they evolve and improve from an older standard but are not compatible. There are many reasons why that can be
I had an old IBM AT had that little power supply. It's rated for 40watts and was used to power a Floppy Drive and Colorado Tape drive. I reused it when I swapped the motherboard out for a Socket3 486. Used it to power the Hard Drive, Floppy and CD-ROM.
That TEAC tape drive deserves a dedicated video very much.
You would need a data cassette, like TEAC CT-600 or Maxell DC-300 (ones with notch on the top).
My guess, than notch indicates that tape drive won't take a regular compact cassette (?)
I’m almost certain that TEAC drive uses the standard audiocassette tapes. Would be a fun mini episode to get that drive up and running. What’s strange is that the drive seems to have a much more complicated mechanism than a traditional QIC drive from the era.
we had some of these drives in high shcool, nope regular cassette would not work, we tried that first, never did find out what kind of tape it used
I agree, it sure does look like it. Found the manual for it on archive.org, but there is no mention about the sort of cassette tape it uses. Interesting in any case. In the maintenance manual there is a drawing of a cassette tape, but it has a weird notch in it. Not sure what they mean by that.
I have the same(maybe) TEAC tape drive in my collection and it DOES definitely uses normal audio cassettes. I have tried and it works fine with what is available today but it has to be blank for it to be able to be formatted for data storage use.
I'm familiar with these TEAC tapes as well. They sure looks like regular audio tapes but they are not. There are some tabs/holes that differ if I remember correctly that prevent the use of regular audio tapes. Maybe it's possible to convert a good quality audio cassette tape and see if it can be made to work. A video idea for Adrian maybe? :)
Part of the difference is the tape formulation, the magnetic coating. It's similar to the variations of audio cassettes, with basic original ones, chrome, ferrichrome, metal, listed as Type I, Type II, etc. I used a similar data cassette drive in the late '70s on a Perkin-Elmer minicomputer.
A similar situation went on with 8-mm and later on 4-mm tapes, they had data tapes, and video tapes for camcorders. Trying to use 8-mm video tapes for data storage was hit or miss, leaning toward the miss side. We ended up fighting with a supplier who would send us video tapes when we ordered data type; I think we ended up switching suppliers.
I remember when I used these machines at GMC Vauxhall Bus and Truck in Luton UK and at a previous company's, IBM would refuse to fix there products if you had non IBM modifications.
This may be why this mod was done so if it needed to be serviced or repaired, the machine would have to returned to it's original state.
The parts were very expensive.
One of the most hard working RUclipsrs- thanks for everything you do Adrian!
Especially if you consider that, according to what he mentioned a couple of times, he does not create RUclips content as his main job, it is just his hobby.
Exactly!
worth every Patreon penny I give!
For an XT system, those desktop publishing apps are amazing. After that insanely slow memory check, whoda' thunk.
My M1 just runs when u turn it on
i buy a new system if i need more mem!
Argh, the slow memory check...I got bitten by that recently troubleshooting a PC with memory isses with no monitor attached. For ages I was thinking that the system was failing to POST, when in fact I just needed to wait a few minutes for the beep.
There's a piece of code by 'Throckmorton Scribblemonger' in the official Apple II Applesoft Basic manual from 1987
This is an aux PSU for the 5150 with it's 63w PSU. There was a round knock-out plug on the 5150 chassis rear panel that would fit this round connector. It's a neat and now pretty rare upgrade item. Neato!
I just got a 5150 that had a Seagate drive installed. The two half-height floppy drives were powered by that auxillary power supply. I don't have the aux PSU but the cable was in the case. Something from a bygone era. I don't see a use for the cable. If I wanted to provide adaquate power I'd replace the internal PSU.
Q&A was a fantastic DOS office suite. Used it for years at my old job, even after moving to Windows 3.1. Didn't drop it until Win95 era.
Loved Q&A back in the day.
Q&A + WP51 was ver common. FP is First Publisher (GUI loosley based on the the AtariST version). The mono card is probably also Hercules compatible, specifically for the HiRes software in mono.
I do remember at one time we did have Q&A installed on one of our computers years ago don't remember when it was pretty sure it was beyond Windows 3.1 but not sure
Q&A was a fantastic database in its day. Too bad Symantec dropped it
It was funny to read that the last modified dates were in 1995. I can only imagine someone using this seeing the shiny new Windows 95 release and needed to upgrade! :D
Swapping power supplies would've voided IBM warranty, especially if you were a company and had an IBM support contract. Having a separate power supply for the TEAC tape drive would've left the original 5150 hardware in place and operating independently from the Everex stuff.
Also, tantalums popping are cake. I can remember working at Netscape in the late 90s and having a dev server decide to blow a few big electrolytic capacitors. Sounded like gunshots and caught the chassis on fire. After hosing it with the fire extinguisher and letting things cool off we took it apart and it had blown holes in the power supply circuit board and the motherboard, as well as putting a dent on the inside of the case.
The round connectors are Amphenol CPC series connectors, “Circular Plastic Connector”. They come in many sizes with lots of pin counts available, a cheap alternative to expensive mil-spec metal connectors.
That's why I replaced all the 3 leg tantalums on my 5150 before I even turned it on! Mouser still sells new ones that look identical.
Ah nice -- didn't know they did. You can't mess up the polarity that way
@@adriansdigitalbasement2 What amazes me.. is that this decent software at 37:05.. is running on 640Kb of memory 😯.. and it must use 1Mb or 2Mb top's in the HDD 🤔............... something like this today.. waste 30Gb or 40Gb 🤢... requires like 16 CPU Cores and 20Gb of RAM at least 😤...
My first job as a computer engineer was repairing and aligning floppy disk drives. The IBM Tandon 5.25" 360k was the first drive I ever did. In my second job I worked on everything else you were looking at on that XT PC. We had a clean room where we rebuilt HDDs and the ST225 was certainly one I have worked on. Replacing heads, platters and writing the servo which I think was Cylinder 0 -1 or maybe -2 with a small servo track writer that you could manually move the heads with. Then we used a Hdd analyser to perform a complete surface test. Then attach the drive to the PC booting to DOS on a floppy, running debug with g=c800:5 to initiate the low level format utility in the controller's ROM. Then finally partition and hi-level format the HDD.
Are you still in this line of work?
@@EddieLeal Hi, yes I am but more with computer comms equipment repair and laptops these days and I repair valve radios as a hobby. Thanks for asking.
I think SASI was Shugart Associates System Interface, and I want to say it was the basis for SCSI.
Just checked on WP and they agree. It went from SASI to SCSI because they didn't want the protocol named after a company.
Just think about the "Centronics" parallel printer interface, or the "Hayes" modem AT command set. Plenty of company names used for products, often outlasted the companies themselves!
I remember SASI drives, and SCSI coming out.
Also the HPIB / GPIB / IEEE-488 instrument control bus, evolving from proprietary to a standard.
Shugart Associates System Interface. SASI is a compatible subset of the first version of SCSI.
IBM proposed annunciating SCSI as "sec see" (sexy).
As I understand it, the IEEE refused to publish a standard named after a company, so SASI was renamed to SCSI.
That tape drive is Techmoan fodder if ever I saw one.
I agree I'm surprised I've not seen something like that although the 8-Bit guy has a video on odd media formats as well
These XT's are great , this is Vintage IBM , These will be nice to Curate and Show as examples of PC's from this Year . Have some games , software and Documentation in plastic saved so you can sell each one when you need to , Great Video :) QC
thats funny that Q & A seems to be better written and ahead of its time then what we have today - the flashy GUI...
The purpose of the "appendage" reminded me of mod I felt compelled to make in the early 2000's for my file server at home.
As a poor college student, the most powerful power supply I could afford was a 300W ATX. At the time, I was running a Pentium II 400MHz in a full tower chassis with as many used old SCSI hard drives as I could snipe on eBay. At one point, the server had 10 SCSI HDDs (10K, 15K, etc.) and two IDE HDDs mounted and I was certain I couldn't reliably power everything from the single ATX supply.
So I scavenged another 300W ATX supply and built a "remote trigger" out of a relay, a large capacitor, a diode to protect against back EMF and an LED. It was energized by the main supply and the relay "turned on" the second supply.
Most of the drives were connected to the second supply, leaving the main system and IDE drives on the first supply and I ran in that configuration for years.
Best. Space. Heater. Evar.
...also very noisy.
The IBM 5150 had a round punchout above the cassette and keyboard ports on the rear panel. That is likely where the round power connector was intended to be placed.
I once had a system that used a card with a complete PC W/Ram and was used as a network syste. You would attach a monochrome monitor to the card and it would use the PC resources for hard drive and data transfer. You could put up to 3 of the cards in a system in order to have a 4 terminal network with the PC being used as the server. This was around 1986, unfortunatelly, I cannot remember the name or brand of the card.
3:10 Oh, neat! My employer uses threaded circular connectors like that, albeit in a 37-pin flavour, in embedded systems. It's pretty trippy to see that sort of connector in a household or office machine from the 1980s. Incidentally, on our machines, it allows for a single uniform connector to be used for subdevices to be powered from or communicate through a bunch of different buses. Like, I have some subdevices where 6 or 8 particular pins are connected for specialized communications, and others where a different 4 or 5 are connected for power plus serial comms.
By the way there are versions of a similar connector I'm some sort that actually have pens that that can be used from full line voltage power and also low-voltage pins in the same connector that's scary stuff!
I know that on some airport X-ray machines this is used for the monitors which is just the little bit dicey to the unwary.
And you know how low voltage in line voltage should be separated although if suitably insulated for the voltage at hand and equivalent insulation it is permitted encode but I don't know if that goes for with connections like this I do know that that is 4 in conduit at least.
And at a church where do we have a organ console that was on the long table where there was both power and of course low voltage the organ company refused to bundle the entire cable because of that it was a code violation to do so even though those connections were right next to each other all the time we later found out that the cabling that was used the insulation was suitable to allow this to be done.
Most electrical tape I've ever used on one cable!
We look forward alternative but yeah won out in the end with just roll after roll of black tape!
I've also heard that they used to use fire hoses for these flexible umbilicals I'd called them on installation Pro is both ends were hardwired so there was no way to slip anything over it after it was installed.
They specifically did not use connectors because of reliability.
Plus there would have to be numerous connectors since there was hundreds wires coming in from the organ console it was actually telephone cable that was being used!
The AC power was a separate cable not to mention a low voltage cable I do believe that might have just been the common for low-voltage!
Although in the organ itself everything was not insulated what one might think.
Since everything was at mostly the same polarity that wasn't necessary.
If there was a short somewhere it would just malfunction.
It was rare to have a short between the common wire and anything else!
Wrangling that cable when the console was moved was like wrestling an anaconda you could say
Also I have seen a similar connector often on a junction box cover.
typically in retail stores here and there just in random places.
I'm wondering what those were used for originally possibly!
And I know those connectors were used on some cash register systems.
I did Salvage a few but having them not just at the piece of equipment the between peripheral is just odd.
20:40 - You can already see some fireworks reflecting from the bracket of the first card connected to the motherboard.
Ha! Guess it was starting to melt-down -- funny!
The cable hanging out of the side reminds me of my A1200 setup in the 1990s. Which consisted of an A1200, with 2.5-3.5" IDE converter ribbon which trailed out of the Amiga case into an empty (except for PSU, 3.5"HDD and CDROM) PC/AT case. Quite a fragile system.
for things that plug directly into mains I made myself a little box that contains a GFCI and a paddle lightswitch so if shit starts to hit the fan I can slap the switch if the GFCI doesnt catch it ... its only tripped like 3 times in the last 10 years but it is nice to have a quick poweroff when the smoke starts coming out without having to touch the device in question. Of course its not the ideal way to do mains testing on mains powered devices but its one step better than hoping that you can yank the cord out of the flaming ball of angry sounds and can be cobbled together for a couple bucks at the hardware store
My father's PC had a similar problem where it would halt after about 1.5 hours of use, turned out that the lower address latch was faulty (the 8088/86 multiplexed the data bus onto the address bus, so these latches were needed)
Wow that tape drive is amazing. I didn't even realize that existed.
At the moment my smallest room is filled with tech stuff waiting for cleaning, repair if needed and to be sold. I'm waiting for someone to move out finally so I have more space and time, but most importantly to be in the mood to do this kind of work. But right now I think that small room would give the impression that I'm a hoarder as well... :( I don't want to be seen as a hoarder!
One's hord is another's collection 🤔
My precious!
Neat video. I love seeing these systems still running after all these years.
I hear ya on bad 90's power supplies. So many were junk. PC Power & Cooling was my go to back then. SO good.
Now it's Seasonic. They go in all of my systems.
Thanks again for another great video. Fun seeing the workarounds that they had back then.
It's been a minute since I've heard someone say the name Everex, I had a few of their laptops before they went out of business, and they where some of the worst I've ever owned having the VIA C7 X86 CPU's in them, as the Windows drivers barely worked, and Linux on them at the time was a true pain, plus overall just being slow as molasses to use. So I'm not surprised the little Everex PSU you had on this machine was crap.
Yes the rectangle on the back panel was the batter pack for the CMOS, a lot of them were removed due to the barrel or other battery spilling its badness on to the board, I had a like model Zenith Data systems desktop. Came from a government office had a network card for a sat network that got struck by lightning
There are all kinds of Everex prototype boards floating around... tho unforutnately I missed all the ones that were from our old office. Everex had some of the first 16 bit and 32 bit display boards that were affordable and any good. Then they had the first 16+32 bit color VGA boards. Their catalogs were pretty boring I don't know why they had such cool stuff like oscillator boards when they didn't seem to have anywhere to sell them! ANyway lots of prototype boards to look for. They sold lots of tape drives and memory cards and drive interfaces. They also made some of the best 286 and 386 computers available. I could tell you other secrets of Everex but am still looking for stuff! So that will have to wait.
Would replacing the power supply void an IBM warranty? The external power supply seems like the kind of thing you'd do to get around that.
That round connector looks like what is commonly called a “cannon” plug. They are pretty robust and designed for relatively easy repair if you have the proper (expensive!) tools, the military uses them as does Boeing - not sure if their competition does, but they are a din-standard connector
I suspect it's a TE Connectivity / AMP CPC connector; they are not the same a military type connector (602 or 62 style), althought the latching mechanism is very similar.
I grew up using Q&A for its word processor. we even used first publisher as well.
40 / 5000
From the Netherlands, a BIG thumbs up! I remember those machines and bringing them back to life is more than awesome!!! I Never expected to see that 'A:\' prompt anymore.
I have a thermal IR camera that is very helpful for finding components that are shorting but not hot enough to smoke. It's a handy tool.
The 4-pin hanging connectors -- Circular Plastic Connectors (CPC) are made by AMP. This is the small cell size version using crimp type pins, compatible with 24 to 20 AWG wire.
I worked on these! It's a booster PS for running full sized and heavy power hard disks in an IBM PC.
I'd recommend replacing the battery even though it seems to be in good condition.
The one on the ram card? He showed later that he'd removed it.
Adrian has discovered the elusive Floppy Killer.
Don't you just love a Tantalum tantrum? Thanks for another interesting video, Adrian and also for encouraging fellow Retromancers to get our Nostalgia high more cheaply!
That Tantalum rocket launcher at 21:21!
Awesome!!! Nothing better than relaxing after a busy workday with tantalum fireworks. It never gets old :)
Used to see ALOT of odd stuff added to PC's in the 90's while working for HP in the Detroit area. Especially around the auto industry, car repair shops, parts manufacturers, and factory floors. Good times when a 'special' one of a kind card or 'box' blew mother boards...almost impossible to fix sometimes.
I used to work on these giant magnet sector mass specs controlled with a specialized PCI card that costed 30,000 dollars.
I accidentally blew one up because I thought the PC was powered off when it wasn't. Whoops.
@@ax14pz107 Right, as a tech you would drive 2 hours for an on-site service call to some factory in Flint, Michigan. The PC would be hooked up to some CNC machine and had a bad mother board. An hour of getting the greasy PC open and the mother board replaced. Of course the PC would be tested without all the 'cards' and it would boot fine. Put the cards back in and power on and the blue magic smoke would appear.
One thing that facinates me is that these computers have not been used for decades and still today they work, they may have a few faults (most of the time), but they still work. I really doubt that a modern PC would be still working in 20 years time. Old PCs are built like tanks and weigh as much, new ones all look nice with its RGB crud and whatever but they are made like disposable items.
Not only was this not used in decades, it was left uncovered in a hostile place (a hot / cold attic) -- so wasn't even kept in the best place. It is amazing how resilient this stuff is ..... I do wonder about modern stuff, but I do tend to think that at least the things without batteries should still be working in 30 years. Maybe? LOL
The hot/cold attic has good points, too. It may get to temperature extremes, but it gets there and stays there for a while, so it's storage temperature and not operating temps. Plus it seems to have been dry, no major moisture buildup or corrosion from if it had been.
I'm not saying it was the best place to store it, just that there are a heck of a lot that'd be much worse! ☺
Adrian I wouldn't be watching you if I didn't want to see standard XTs! Please do give all the details you want!
My sister-in-law used PFS:First Choice back in the day, it was a rough equivalent to others suites like Microsoft Works or Tandy Deskmate, or later more expensive ones like Lotus SmartSuite or Microsoft Office. It had word processor, spreadsheet, database and more. Not bad at all, especially on machines that weren't top of the line.
Wow, just remembered MultiMate, and the set of programs called ChartMaster, DiagramMaster, and SignMaster. Easily about 30 years since I last used them. Or IBM's DisplayWrite 3 and 4 word processor programs, that stored the text internally in EBCDIC instead of ASCII.
Yes it would be cool to see it working again.
Thanks for another awesome PC Archeology video, Adrian! Your retro videos are the highlight of my RUclips watching every week!
Glad you like them!
I second that
I look forward to seeing you troubleshoot & repair the failed motherboard (because I have 2-3 old IBM PCs waiting their turn). I'm surprised that you didn't have the needed cassette tape(s) to test that portion of the system, especially since you had a complete diskette cleaning diskette "kit." Hopefully you will go ahead and test/troubleshoot/repair the cassette drive unit and show it working on one of these PCs.
My schools senior class was the first to have a computer literacy course as a requirement for graduation. We used IBM PC's like this.
Love the print shop software. Made many things on 🍎 computer in the 80s in middle school making banners on dot matrix printer.
It was probably an aftermarket kit. So, the power supply was supplied so it could be used on a wider range of PCs. As PCs were in their infancy. You ordered a PC with options provided by the manufacturer. IBM being a prestigious name at the time probably wanted a very premium price and the aftermarket solution provided more cost effectiveness to the customer. That part would have been added by the customer or the dealer. After market solutions were most likely installed by a PC dealer. It would go well with my Epson LQ-2180 which, I still use with Windows 10.
Used to use that publisher software on a Mitac XT clone belonging to my parent's business. Can remember the C:/pub directory. The GUI seemed pretty advanced to me at the time.
Hey Adrian - channel name suggestion.
If you have Adrian's Digital Basement, why not make this "Adrian's Analogue Catacombs"?
5162 owner here, that panel on the back indeed is for a battery, the same kind of battery that IBM PS/2s and presumably the AT also used.
I feel like I was left hanging with nothing else done with the tape drive, but otherwise I enjoyed this installment. Thanks Adrian!
I thought it was the RAM because of the stack error too, but then you went and said it in the video so I won’t seem so clever for having thought of it :) here’s to feeding the algorithm
SASI is "Shugart Associates Standard Interface". It predated SCSI by a couple of years. SCSI is based on the SASI interface.
Im enjoying the 2nd channel stuff keep it up. its more like what you did before COVID and the Mail call stuff with the bags of sweets on the main channel
Another good video Adrian! Thanks for sharing with us!💖👍😎JP
these are nice and chill to watch first thing in the morning, well except for that cap blowing i guess
Most Tape Drives of the time used a kind of SCSI controller, not enough to run a hard drive but plenty to run the tapes.
I love how you used to get the 301 error when booting, then next line it would say F1 to continue. Uh.. Sure
Cleaner than rigging up two 62.5 watt PC OEM power supplies!
Another computer dinosaur. Love these videos. Very educational/nostalgic. Thank you for sharing your knowledge with us.
Spinrite II .. brings back memories…
That spark looked fantastic!
Everex made some of the fastest x86 systems on the market at the time. And their equipment was grade "A" quality. As for SASI, that stood for "Shugart Associates System Interface", and was the predecessor to SCSI. Wikipedia says: "ANSI developed the specification as "SASI" and "Shugart Associates System Interface"[7] however, the committee documenting the standard would not allow it to be named after a company. Almost a full day was devoted to agreeing to name the standard "Small Computer System Interface", which Boucher intended to be pronounced "sexy", but ENDL's[8] Dal Allan pronounced the new acronym as "scuzzy" and that stuck."
that was a fun video, thanks for sharing..
Throckmorton Scribblemonger has been sample data that I've seen before, but I can't remember where!
That's the first time that I'm seeing something that definitely looks like it's designed for the round hole of a 5150. Interesting discovery!
As for that tape drive: Regular audio tapes definitely will not work. You need special cassettes that have special tape and a notch that tells the drive it's a legit tape (and that notch will also keep you from inserting the cassette bottom side up).
By the way I have a batch file somewhere that I once made for FastBack, that will run it in DEBUG and will use breakpoints and go-commands to skip over the code that detects whether you have the original FastBack program disk in the drive...
The theory is 12V Tants tend to go first because 12V is close to their original 16V rating, so there is less headroom for any breakdown.
That matches my experiences with them at an electronics manufacturer while testing boards and assemblies. Tantalum caps in backwards were a problem, too. My favorites were the ones that leaked a little silver teardrop when they failed. 😭
Remember, Adrian, the way to get more views and likes on YT is to make something go pop! Well, you somewhat succeeded; let’s see if we can take out any more caps, eh?
One solution to shorted tants - use a bigger power supply.
Although if you start blowing tracks off the board, maybe you've gone too far.
@@paulstubbs7678 yeah they actually call that power blasting also good for finding other shorted components although once there was something shorted on the board that was not a component and well there's a fine Trace put this way nice smell of extra crispy circuit board!
And one capacitor or two going pop once that short opened due to that Trace becoming open circuit happn hooking up I didn't realize what had happened!
Pretty sure that Trace opened and then to Cap's poped.
Those Line Filter capacitors on some of the old equipment are the worst when they go.
That are typically used in line filter applications.
and some others the ones that are amber transparent color.
Had one of those puppies go off on workbench once!
I was doing some repairs on old piece of gear for somebody.
Remember somebody ran downstairs and said what just happened
and they just about got sick!
And once I found out about what happened you better bet anytime that I got in a piece of equipment that had those!
there was some pre repair work before even starting.
at least after I knew what the issue was and the device was not repairable!
26:18 That 40-year-old hard drive just spun up and started reading like it's no big deal! 🤯
I know you know what you are doing, but I can't be the only one shouting "Stop touching it when it is on!" XD
As far as the system failing the way it did, I'd check the memory. First check the 5V rail to make sure you have no shorts pulling it down. Since it isn't showing any video I'd start with the parity bit on bank 0 then move on to the rest of bank 0. Also check the ROMs. One thing is for sure, a Bank 0 parity fault will stop the machine from POSTing and there will be no beep codes.
That there was enough demand for Everex to build such a thing is a damning indictment of IBM's (lack) of wattage in the XT power supply.
I believe the original power supplies were rated for 65 watts. My Seagate ST-4096 probably would have had a bit of trouble running off of that supply.
When the IBM PC came out I have a feeling IBM was thinking well people will just come to us for all their upgrade needs, and we will make them to run off this PSU, and they will never need anything more. Boy where they wrong, just like how they bet the farm on Micro Channel Architecture. Don't get me wrong, as I love IBM design from back in the day like their Thinkpad laptops, ThinkCenture desktops, and keyboards(I still use an IBM KB-8923 on my work PC with an active PS/2 to USB converter) but man at times they trully did make some stubborn boneheaded decisions.
I figured that C:\PUB was some desktop publisher. I used to use First Publisher on my Tandy 1000A (and they later released a DeskMate 3 version) and now that I think back on it I think C:\PUB was it's default install directory.
SASI - Shugart Associates System Interface
Was eventually extended to become SCSI-1 but ANSI refused to standardise it with a company name in the title.
Yeah i often don't get to really working till 4:20 pm myself lol
Shugart Associates System Interface, the first embodiment of what is now known as SCSI
JESUS H CHRIST MAN YOU JUST CHARGED UP THE HIGH VOLTAGE CAPS LIKE 60 SECONDS AGO!!!!!!!!!!!!!!!!!!!
34:32 Scribblemonger Throckmorton appears
Ha, I had a similar experience tonight with a blown RIFA...that smell.
We didn't have a hard drive in our XT; just two floppy drives. :)
fire is good it makes it easy to fined the problem
34:32 Oh, hey!
Stack error sounded like the 0 page of memory died and may explain no POST, it probably either uses that memory during it or halts if it detects any bad memory in that page
In the words of Steve Martin during the famous SNL skit from October 1979, "What the hell is that?"
ruclips.net/video/DU_Gd623HJo/видео.html
Some say, that IBM 5162's chassis is a bit shorter than a 5150/60 chassis, so you can't fit full lenght cards in it. Is it true or not?
A 4 discreet diode rectifier.... Noooo, it's A FULL BRIDGE RECTIFIER!
Looks to me the external power supply is just a standard switching power supply shoehorned into a custom case. Could be why the bulge in the perforated cover. On the pc board markings, I believe the 94V-0 portion is the UL flammability rating or some such. Another way of checking for polarity markings might be to look at the pads and/or the solder mask around same… one is likely to be square.
Q&A, now that's a name I haven't heard in a long time!