IBM 5155 Part 2 : Light at the end of the tunnel
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- เผยแพร่เมื่อ 2 ต.ค. 2024
- In Part 1 of this series ( • IBM 5155 Part 1 : Surg... ) I introduced my "new" or "second" IBM 5155 that I picked up.
So I am pleased to announce that we have found some light at the end of the tunnel. The luggable is running again ... kinda .... and all of the components are back in the case.
In this video we'll be fixing the floppy drive, memory card, videocard, harddrive and keyboard .... that's about ALL of the components that this luggable has (minus the ones we fixed in the previous video....
But we are well on our way in finishing this project .... This series will get one final part where we look at the exterior, and fix a hard drive / controller mismatch.
But for now .... enjoy this one ......
Varta batteries are deadly for most common systems. Keep up the nice job. Greetings from Steven from the Netherlands
Ah, memories...the buzz of death. Great series, many thanks!
Thx a lot ... make sure to subscribe .. lots more stuff to come !
Thanks! I just got my 5155 running again with the help of these video's. I still need to fix one of the floppy drives, but after seeing your video's, I'm confident that I'll get it fixed.
icecreammm2 cool .... glad you got it up and running again and the videos helped !
@@RetroSpector78 I'm looking into buying an XT-EDI solution for my 5155. Any Idea where these can be bought in the EU for a reasonable price?
@@icecreammm2 no there don't seem to be any "big" shops in the EU that I know that sells them. You can find them sometimes on ebay. Otherwise official channel via the US (TexElec) where you can get them assembled or only the PCBs if you feel like creating one yourself. Or you can perhaps check the forums (vogons , vcfed, amibay) to see if there are local sellers.
Nice job, well done, I have learned a lot from these 2 videos, thank you very much for sharing. Love these old 'luggables', had an old Cordata 286 luggable once, wish I still had it.
I had so many vintage computers when I was in Belgium, had to sell them before moving to US. These videos bring back the good old memories when I see Dutch or French OS.
At least I think over there in the US you also have a thriving vintage computer market :) A lot more than in Europe. Not always easy to find these old machines.
RetroSpector78 Brussels Vossenplein, 2dehands.be and Marktplats.nl were my main sources for these machines. But, Vossenplein was really an interesting flea market. I have picked my Osborne, Grid, Kyripto, Compact luggables with red plasma screen, IBM 8086, 286 and 386 computers there. The online was more like a source for accessories.
@@oturgator Been thinking about checking out those markets for a while now ... I tend to find a lot of stuf by word of mouth ... got a really big haul of retro stuff a couple of months ago just because I happend to be in a thrift store and I asked the clerk if they had old computers. They didn't. But a customer overheard the conversation and invited me over to his place where he had an entire garage of stuff. I could have it all for free if I took it all :)
@@RetroSpector78 The flea market at Vossenplein (www.bijzondereplaatsen.nl/belgie/brussel/vlooienmarkt-vossenplein.htm) is an amazing place. Even here, where most technology originated from, there is no such flea market that can remotely be comparable. I am more into calculators and pocket computers. I could be able to find a HP 19C, HP 10C and a HP 75D (with VisiCalc Rom) in one day. I bought a HP 11C for -17USD, yes negative! The Compaqs were almost showing up every other week, the 5155 that bought was with the hard drive and the Osbourne came with full documentation and with the code that previous owner saved on floppies. I had a Amiga 2000, various home computers and software like the OS/2 Warp, early versions of DOS, Windows (Either in Dutch or French), Cobol, etc. All I am keeping from that time are some HP 41C series calculators and HP-IB accessories. If you haven't been there, I suggest you to check it out, but you need to be there early, say before 6:00 am. The "professionals" are really not leaving much by 7:00.
You're lucky the keyboard issue turned out to be a contact problem.
My Model F actually had dirt between the contacts and getting the key assembly on one of these apart is a b***h and a half.
I remeber my grandfather recycling hundrets of this vintage pc , some of them they wore up to 10k us dollars new and the recycle value was about 5 dollars per unit even less the suppliers wore a bit selfish as they were not allowing resale only recycle .This old pc become very valuable and rare due extensive recycling fanatics
8:50 "Let's recap a little bit" - Iseewhatyoudidthere.bmp
I have been watching these videos with interest over the last few days as I attempt to get my 5155 working again, so thanks for the great content! Did you ever sort out the hard drive/RLL controller mismatch? My 5155 has exactly the same configuration - ST11R (RLL) controller card and ST 225(MFM) drive but I am a bit worried about "over formatting" the drive to 32mb like you did.. did you have issues with doing that in your machine?
I just had the same thought after watching the video, as you can see at its end it's the very common and well known ST225 hard drive which is definetly an MFM model. In the internet you hear different opinions about if it works to use an MFM drive with an RLL controller or not. I have no experience about it my myself, so it would be interesting to know if this configuration might work even after a few years.
@@davidhorst3766 I did the "overformatting" on my drive and it worked, but it only lasted a few months before the boot sector "died" when I got to about 50% disk usage.. havent tried to fix it yet..
Will there be a final part someday? Those old portables are very interesting machines. I'd really like to have some oneday.
It's nice to watch the repair work. But do some modern task on such a machine, be patient!
where is the part 3???
It was awesome that you were using DOS Navigator to move files around with!
this is Norton Commander I think ,not DOS Navigator
Your repair is very similar to my 5155, right down to the strange CGA card fault. My theory with mine is that it had shorted on the case as one of the plastic standoffs was rattling around inside loose. It’s worth persevering with the repair as apparently the CGA cards used in the 5155 were optimised for the amber CGA screen. Interesting that you has a ST225 formatted as RLL, but from you video I think you already know that :). It’s great to see such a thorough and well documented repair video.
Thx a lot ... glad you liked it .... Yeah it is very tight up there, especially for the CGA card ... my plastic standoffs are still there but I often find myself putting in some carboard to add some space :) The CGA card is very challenging ... still don't have a fix for it ... and the replacement I have doesn't seem to render everything very nicely on the amber display. But haven't given up on it yet :)
@@RetroSpector78 do you have a TL866 ? If you do, you should be able to test some of the chips found on the CGA card, this should help figuring out the issue maybe.
RetroSpector78 The 5155 CGA card has a certain amount of mystery surrounding it.
It’s said the CGA card in the 5155 was unique in that it was capable of displaying more shades so the monochrome screen looked better.
However, my suspicion is that all very late revision cards had this display upgrade regardless of application.
The “wrong” 1501486 card I had in my 5155 looked terrible (you can’t even read the menus in basic) but I found a very late 1501982 (week 50 1986) card that worked very well. My suspicion is that all later cards will work in the 5155. However this is all theory as IBM never documented the change!
Later cards can be identified as they have more resistors near the composite connector, but I think the 5155 upgrade came as a later revision to this late style of card!
Did MS-DOS want N or P for Ne or Pas in french?
The Kaypro's might be worse to remove the floppy drives on, due to the drives being encased in heavy shielding from the CRT next to them, again I had to use a ratchet to get them out
I have a love-hate relationship with these machines. Think they are really nice but extremely difficult to service and clean.
Looks like the same floppy drive they used in the PCjr.
That does not look like Seagate st-138R 20:35 .The st-138R is an 3.5'' hard drive.
Correct, I mentioned it in the description (not sure in the video) that there was a controller / disk mismatch ... only saw that it was an ST-225 when I removed the floppy. It came configured as an st-138R and had an RLL controller (that is not supposed to be hooked up to an ST-225)
Correct me if I'm wrong but the ST225 is MFM not RLL. So it would be an MFM interface.
i think it's a mismatch, an mfm hdd w/ rll card. i predict he'll install an mfm card in next video, & reuse the rll card in another machine. take care & stay safe.
Late reply. RLL controllers use MFM drives. They use a different encoding, giving an additional 50% storage. So a 20MB MFM drive with an RLL controller yields 30MB.
@@JamesPotts Didn't know they were interchangeable.
must clean the corrosion in the front chasis
Have you considered trying to replace the Varta battery with a coinsell CR2032 on the memory card's PCB?
bundesautobahn7 yes I have, but focus now was to get all of the basic stuff up and running ... already became a bit lengthier than I would have liked :) might do it in part 3
Does this really work? The coincell is a different voltage, and wouldn't the charging circuit in the PCB fry the coincell?
@@audunm.gangst1166 folks who do the coin cell mod install a diode to prevent trying to charge the coin cells. multiple coin cells in series to match the replaced secondary [ie rechargeable] batt, if necessary. take care & stay safe.
Interesting vids again as always and more than a few pointers to get upwards in that learning curve... Specially as in our IBM 5155 Portable we got in three weeks ago that first capacitor you replaced popped on first bootup... Yup I was presented with that dreaded smoke (and smell)... So Tnx for posting...
disarm the hard drive, turn off the first disk, and the rll controller ask install, but in the ST you will need the 2.1 version
because the errors in the disk can be past, the old version the controller cut de low format when find an error.
So when I was much younger we had an older at machine. Or XT. Or both. But anyways the hard drive was messed right up so I ended up formatting the thing a good 60 times I think. Including the scandisk to mark the bad sectors. The same errors would eventually repeat every time and I would have to start again. What a great learning experience though. I wonder if lubricating the bearings or motor or anything on the hard drive would help.
I got 4 IBM 5155, all are in sucking condition, this help me a lot
Glad I could help. They aren’t the most enjoyable computers to work on.
is the hdd pata drive?
I hope you pulled the motherboard to check for corrosion underneath, as with all the corrosion to the bottom screws, I'd be very worried that it was left in standing water just below the motherboard itself.
It looks like the big screws on the floppy drive were supposed to just be loosened, not removed since there's a slot in the plastic to slide out the drive after removing the smaller screws.
Maaan where do you get this things
hahaha nc :D good works.
tantalums, if one is dead, more to follow, just order ceramic replacements all at once and get them gone, they were great at one time, but now ceramics can replace the majority of them
man, that's a lot of work for one computer!
Haha... tell me about it .... but it’s all good fun and you end up learning a thing or 2 ... it’s the second 5155 I had the pleasure of owning ... so experience with the first one came in handy....
Totally worth it.
Good work. I enjoyed the video. Btw why didn’t you replace all the tantalum caps?
Gotta leave something for part 3 right ? :) Got some on order and other machines also in need of some recaps... capacity issue.
RetroSpector78 looking forward for part 3.
how hard would it be make a custom cable for those internal components?
recap the monitor board, have an issues
Already enjoyed the first part, looking forward for the third :D
Third and last one ... hopefully :) Some other machines also need my attention :)
@@RetroSpector78 Looking forward for them too :D
@@Hutschnur Working on my Tandy 1000 TL right now that has been sitting on my shelf for a while ... want to get it out this month as there is some kind of #septandy thing happening right now
@@RetroSpector78 Yep... couldn't see it until now... lots of work the last two days.
#septandy was a great idea! I've found your channel over that hashtag and another called "8-bit and more".
Hutschnur think we will need an #octandy soon ... footage for 2 more parts.
have you ever seen the GE workmaster
our ee dept technicians had a ge workmaster, back in the day. all black, as i remember. they used it to program ge plcs, one of the many brands of plcs we used. gould/modicon, ti, ge, ab, ... . take care & stay safe.
@@dLLund the ge workmaster was not only black it also had a 3.5in floppy and a esdi hdd in it
verry like
"Let's recap a little bit" - funny.. I had access to a lot of these machines during the 80s and 90s and lots of PC parts, so enjoyed building them up as much as possible, installing hard drives, ram, etc. My guess, probably as well as other people here that they previous owner didn't park the drive before moving it which is especially important with a 'so called portable' machine.
"Park the hard drive..." We're dating ourselves here, aren't we? As soon as they came out with the magnetic actuators in the early IDE hard drives, that term died out fast.
@@BlackEpyon Yes, of course, but it's still alive and relevant to those of us today who enjoy the hobby of restoring, and using the legacy machines. This means parking the servo motor (usually a stepper) driven heads. You are 100% correct in stating that once the voice coil type head actuators came on the market it was no longer necessary because the spring action would cause the heads to retract off the platters when power is removed. I feel no shame or guilt in dating myself. I've been working on a PC-XT restoration recently and wrote an assembly language interface routine to the RTC card that came with the machine since I didn't have the software for it.. It was an enjoyable hobby project. FWIW the clock card has a MM58167 chip on it.
Cheers!
@@fredflintstone8048 I actually recently got myself an MFM drive with an XT machine I picked up off of eBay. It was listed as parts/repair, and I know for certian that the hard drive wasn't parked, since the machine let out the magic smoke when it was last tested (blown tantalums, it boots now). But I don't even know if the MFM controller works. It's ROM chip is one of those older types that can be cleared with UV, and was missing the sticker. I can read some data from the ROM chip, but without any visible model number on the card (just says "Modular Circuit Technology MCT-HDC"), I can't decipher the jumpers, or lookup to see if somebody has a ROM file I could compare to see if the ROM is still good.
It's no loss if I can't get it working, since I wanted to put in an XT-CF anyways, to free up the drive bay, but it WOULD be nice to be able to get it working for posterity, and for the sake of the hobby.
@@BlackEpyon It would appear that documentation for that controller may be hard to come by. You might try a command in debug something like -g=c800:5 which might possibly invoke an internal routine on the card for dealing with the drive. This might help: th-cam.com/video/uWWNbpd56Xs/w-d-xo.html
7:47 some of those traces look like theyre bubbling off the board!
happens a lot on 80's 90's pcbs but what wrinkles is just the paint not the copper...and although its wrinkled it is still very resistant and doesnt peel off easily
@@MrHBSoftware thanks for answering, i think ive seen it before myself
Man, these videos bring back so many memories.
VARTA "SafeTronic"
I laughed a little too
why some capacitors aren't totally vertical(angled down)?
Those are known as axial capacitors, they were most used during the early days of electronics with vacuum tube equipment until the 70-80s when the transistor became more popular, then the axial capacitor was too big for printed circuits so a vertical position was much more compact and convenient.
@@silentbloodyslayer98 thank you so much for all
8:22 aren't that diodes tho?
no...they look like big rectifier diodes but its just a wire running through a ferrite bead...diodes always have a stripe on them
Imagine how much money some business exec would loose if he constantly forgot to "park" the hard drive before lugging this thing about.
Why the 4 dislikes? This is a great video!
Thx a lot .... appreciate it. Not really worried about it .. it's a youtube thing :) Glad you enjoyed it (and the majority also of the viewers also)
ST 225? That's a 20MB drive, right?
Nice cliffhanger, by the way ;)
Yes it is ... and it is also not an RLL drive ... more on that in part 3 ...
@@RetroSpector78 My memory on this is dim, I must confess. What I remember is this: One could take an old MFM drive, and upgrade the controller to an RLL one. Perform a low level format, and +50% disk space appeared out of thin air for free. So using an ST 225 and re-format it with RLL would indeed give 30MB. Looking forward to the 3rd part ;)
Martin Erzberger that’s 100 % correct (due to the sectors / track increasing from 17 to 26). Reliability however is another issue :)
@@RetroSpector78 exactly, the reliability...the drive was ailing badly when you got it. I assembled hundreds of clones back in the 80's, I can tell you that RLL works but is very bad for MFM drives. Get yourself a WDXTGEN and take the 10MEG hit, your drive will last through the life of your machine...
I just recently found your channel and I'm enjoying your videos...keep up the good work!
I enjoy your videos. Where are you at to have a French 5155? I never see any of these for sale near me.
My first one I picked up in Paris, second one was from Holland. These french msdos boot disks came from the first XT machine I bought in the French speaking part of Belgium. When I started I hardly had any floppies, and some of these french floppies are still in heavy rotation on my desks :)
But what do you use it for?
Besides the fact that it looks super cool with the built in display, you can also hook up an external cga display. It is basically an ibm pc xt so runs all of the same software. None of these retro pc’s have any practical use, but a lot of people find it interesting to tinker with them or run old software and games on them.
@@RetroSpector78 thanks for your answer!
The best TH-cam channel ❤️
Woo hoo!!! :)
One of the coolest screens I’ve ever seen.
How did you format a 20mb drive to 30 mb? Lol
Jay Brooks the RLL card can pack in more sectors than an MFM card.
@@azzajohnson2123 not really. The RLL drives were designed with heavier media. The card called it a ST138, and the drive was an ST225, guessing the WD controller card has been manually configured or came w a ST138, now being used with a different drive.
Nice restore. Why did the HDD act up?
Probably because it's a 20MB MFM hard drive formatted to 30MB using RLL. Sometimes you can get away with it, but more often than not you get frequent errors that creep in.
Stepper motor based head arms HDDs have one cylinder per step of the motor, so the controller asumes than the track is always aligned with the head. With years, thermal expansion an contraction and wear they get miss-aligned. So you may Low level format the drive so it gets re-aligned. Modern voice coil based head arms don't have any steps, they look for the tracks and get self-aligned every time.
Also the magnetic field of the old data may be faded out.
21:40 What is that D:\ drive?
21:52 This looks like 8087 benchmark
It's the office demo drawing rendering in AutoCAD 2.6
Zankuhaaa! D drive was an xt ide board + CF card I installed to copy some stuff to the internal hard drive.
I think I forgot to edit that in despite having lots of footage on it. Will put it into part 3
@@RetroSpector78 Didnt know that there was an Autocad at the time of XT. On the other hand Ive seen reviews of XT class PCs that were produced in early 90's, so its plausible. That drawing speed is casual, indeed.
fradd have had several XTs that had autocad installed. Must have been brutal drawing with it ... but stil, probably faster and more convenient in some ways than doing it with pen and paper :)
as you know, the tantalum short - why do you take the risk to repeat this failure by not replacing them all...
You don't need to solder such long loops to bridge the pins
murks
Amazing