• Please review our updated Terms and Rules here

First IBM 5155 fixed!

mykrowyre

Experienced Member
Joined
Jan 28, 2019
Messages
171
Location
Saint Augustine, FL
Hello all, this is my first post, I can't believe I hadn't found this forum in the past.

I was doing my daily check for vintage (usually Commodore, TRS-80's, Atari, etc) computers on CL, and I stumbled upon an IBM 5155 (something I'd never actually seen before). It was still available, but not working according to owner. Would not power on, but would try if video card was removed.

I convinced the seller to meet me that night, and all looked good until I noticed one floppy had been removed. I asked and he said "oh I decided to keep one, I mentioned that in the ad!" at which point I got very upset because the ad pictured both floppies and no mention of one being removed. After some begging and pleading on my part and showing him his ad, he relinquished the drive which was still in his trunk. Apparently he forgot to click save after changing his ad.

Anyway after that we had a nice long chat about vintage machines and all good.

Got the machine home, and fan would spin if I removed the video card, but no beeps. I was just watching it waiting for any signs of life when "pop" it went dead cmopletely, no fan nothing.

I stripped it down, and removed the power supply. Looked inside and it looked fine. Connected a light bulb across the 5V lines plus two IDE hard drives, and it fired right up. Yay! PS is good!

Then I started looking for busted caps and I found one, C56. I figured it must be a 12V filter cap for one of the card slots but wasn't sure. Removed it... but still no luck.

Googling lead me to minuszerodegrees where I found a wealth of info! Holy cow! His info lead me to C58 which I tested and found shorted also. Removed!

Then, remembering the it would not work with video card installed, I went over the video card carefully and found another 10uF Tantalum shorted, and decided to replace that one with a 10uF electrolytic (all I had on hand).

Put it all back together, turned it on and was rewarded with BASIC on a beautiful amber monochrome screen! I have always loved amber monochrome!

IMG_4156.jpg

Unfortunately neither DOS boot disk I have worked. I lubricated the rails and still no luck ... I'll clean the heads with alcohol and try again, failing that I guess I'll need to buy some disks.

Then of course an XT-IDE card : )
 
Nice.

I recently got a 5155 myself, Yours looks really clean, does it have the back doors?

Mine isn't able to boot off floppy either, I haven't opened it yet to try lubricating the rails.

How much Ram do you have? Were there any interesting expansion cards? Did the seller include any software?

I have my eyes set on getting one of the XT-IDE cards with slot 8 support for my computer.

I have a saved search on Craigslist for old computer hardware so I don't have to check it every day, And a 'wanted' post of my own I refresh every 90 days.
 
Yeah gotta have an XT-IDE, When i first got my 5155 it was dead, A couple of shorted tants, replaced those and it fired up but both floppy drives were not working, It turned out to be the drive hubs in both floppy drives partially seized, The motor couldn't turn the hubs so the floppy discs were not spinning properly. A good amount of lubrication got them working again. I need to get my arse into gear and finish building the XT-IDE and get that fitted.
 
Nice.

I recently got a 5155 myself, Yours looks really clean, does it have the back doors?

Mine isn't able to boot off floppy either, I haven't opened it yet to try lubricating the rails.

How much Ram do you have? Were there any interesting expansion cards? Did the seller include any software?

It came with a ram expansion so I have 640k. There is also a 2400 baud modem installed, and just the standard CGA video card and floppy controller.

I got two disks, both copies.

"DOS 3.2 with sidekick (?)"
"DOS 2.1 Ram Basic, Auto Date, Time, ScnSave, IDir, Hercules HBasic, HBasicI, HGC"

Looks like a basic compiler?

At this point I think it's more likely the drives need further work than the disks are bad. These disks seem to last forever!
 
...both floppy drives were not working, It turned out to be the drive hubs in both floppy drives partially seized, The motor couldn't turn the hubs so the floppy discs were not spinning properly

Thanks for this info! I was just trying to figure out the drive issue and this will save me some time.
 
Forgot to mention, I only have the bottom of the rear door. Top half is missing. Bottom half is intact, so I removed it for save keeping. Maybe I could trade it to someone who needs it for something I need :D
 
Yeah gotta have an XT-IDE, When i first got my 5155 it was dead, A couple of shorted tants, replaced those and it fired up but both floppy drives were not working, It turned out to be the drive hubs in both floppy drives partially seized, The motor couldn't turn the hubs so the floppy discs were not spinning properly. A good amount of lubrication got them working again. I need to get my arse into gear and finish building the XT-IDE and get that fitted.

My drives had the exact same problem. Sprayed the heck out of them and spun them until the loosened up and then cleaned them well.

XT-IDE will be next.
 
Back
Top