Issue with IBM XT 5150

[Claude25]

Hello. I have retrieved my old IBM XT from the penthouse and I am trying to resuscitate it. The LED of the HD blinks once and it stops in less than 1s each time I switch it “on”. Proceeding further, I have dismantled the PSU (disconnected from mother board, floppy and HD) and tested it unloaded. I can hear a “click” from the small relay inside the PSU but not voltage, 0V on any of the cable terminals. The fan does not rotate meaning that no power is there. As I suspected aged capacitors of being a possible source of short circuit or capacity loss, I replaced them all: the PSU keeps behaving the same. One click and no voltage… Did somebody experience the similar trouble and would have a hint ? Thanks in advance. Claude

 

[modem7]

Hello. I have retrieved my old IBM XT ...

Hello Claude. I presume that the title of the thread should be "Issue with IBM XT 5160", because it the IBM XT has a model number of 5160.

Lots of IBM XT (IBM 5160) information at [here].

Proceeding further, I have dismantled the PSU (disconnected from mother board, floppy and HD) and tested it unloaded.

Unloaded. That, in the vast majority of cases is invalid, because the type of PSU used in the IBM 5150/5160 usually requires a minimum amount of loading (i.e. shutdown on under-loading or over-loading).

As I suspected aged capacitors of being a possible source of short circuit or capacity loss, I replaced them all: the PSU keeps behaving the same.

But that would be with the PSU being unloaded, a probable invalid testing scenario (depending on the make-model of PSU).

Follow the IBM 5150/5160 diagnostic procedure at [here], and see where it leads you.

 

[Claude25]

Hello. Thank you very very much for your support. Appreciated. In fact it is a 5150 I turned into 5160 by adding a HD Seagate ST412 (10Mo or 20Mo...) I do not remember. The PSU was sufficient (130W). I did not realize that the PSU had to be loaded. Will of course make all tests.
Regards from France.

 

[modem7]

Hello. Thank you very very much for your support. Appreciated. In fact it is a 5150 I turned into 5160 by adding a HD Seagate ST412 (10Mo or 20Mo...) I do not remember. The PSU was sufficient (130W). I did not realize that the PSU had to be loaded. Will of course make all tests.

I can see how some people can think of the IBM 5160 as a 5150 that has a hard drive added, together with a PSU upgrade. But most of the difference is in the motherboard and BIOS. Your computer still has a 5150 motherboard and BIOS, and so you should refer to your computer as an IBM 5150 (and treat it as a 5150).

There is lots of IBM 5150 information at minuszerodegrees.net

Your 5150 was stored away for a long time. In my experience, for 5150's in that condition, the most likely problem is one or more failed tantalum capacitors on the motherboard (see some history at [here]). If one is short circuit, it will overload the PSU. But short circuit tantalum capacitors also occur on cards and on the floppy drive. You wrote that you replaced capacitors, but I suspect they were ones in the PSU.

Again, try the diagnostic procedure that I pointed you to. If there is a shorted tantalum capacitor on the motherboard, the procedure should lead you to it (or narrow the field down).

Tantalum capacitors sometimes explode violently, so perhaps wear safety glasses if the motherboard is exposed to your face.

Regards from France.

Consider adding your location to your profile.

 

[Claude25]

Thank you so much. Indeed Tn capacitors seem being a real problem.
By the way, not especially proud of being French

 

[Claude25]

A big hand to modem7 : my 5150 is back to life. To get the familiar A> of the DOS (see pic as evidence). I had 1) to remove 2 Tn capacitors on the motherboard (by the way the diagnostic guide is fantastic), 2) to remove one Tn capacitor on the RAM extension, 3) reinstall my 2nd floppy and boot on DOS floppy. The IBM refused to cooperate in booting on the HD which makes a terrific sound (Seagate ST 412). At the moment, I did not dare to unseal and open to check whats is wrong. Any advice to fix it ?
What surprises me is that all DOS commands came back to my memory !
THANK YOU VERY MUCH FOR YOUR KIND SUPPORT !

 

[modem7]

my 5150 is back to life.

Good. I added the failure to the list at [here].

The IBM refused to cooperate in booting on the HD which makes a terrific sound (Seagate ST 412). At the moment, I did not dare to unseal and open to check whats is wrong. Any advice to fix it ?

Presumably, the hard disk controller is displaying a "1701" error at power-on time.

If your 5150 was put into storage in a working condition, then I think the noise is most likely related to deteriorated lubrication in the ST-412's spindle bearings. Maybe you could attach an audio recording of the sound. It could be that multiple power-ons of the drive may slowly get the ST-412 going again (e.g. possible de-solidification of lubrication) (e.g. possible redistribution of lubrication).

 

[seaken]

Welcome, and we won't hold being French against you! I'm a New Yorker, by way of Seattle. I would love to visit France one day. Go ahead and post your location when you get a chance.

Yes, I agree with modem7. Adding a hard drive to a 5150 does not make a 5160. They are different in more ways than the existence of the hard drive. In fact you could have a 5160 without a hard drive.

I had an RLL drive that was not spinning. I turned it upside down on the case while troubleshooting something and when I turned on the computer with that drive sitting there, upside down, it spun up and booted to the C: drive! I would try several things you might read short of opening up the drive. Unless you have a proper clean room.

Seaken

 

[Claude25]

Thanks to both of you. You are most welcome to Besançon France. Really ! To be honest, I did not find the way to post my location (my IT knowledge is rooted in the 80'). More seriously, I did not pay a lot of time. Concerning the HD, a (convenient) feature I added when I was using the machine during my engineering studies, I am hesitating in putting it back. Useless nowadays and maybe better to keep the IBM 5150 untouched (we say in French: "dans son jus") and m ore valuable as a collector item. I have a big number of floppies : yesterday I restarted "Multiplan". I am wondering how we could work with that! Will tray not to open the HD. Its noise in horrific, like a vacuum cleaner.

 

[Claude25]

Forgot to add something important when its about checking the PSU : the PSU cannot be verified without being loaded. This is very confusing. I lost a lot of time in believing that the PSU was faulty because it was fully disconnected.

 

[Claude25]

Welcome, and we won't hold being French against you! I'm a New Yorker, by way of Seattle. I would love to visit France one day. Go ahead and post your location when you get a chance.

Yes, I agree with modem7. Adding a hard drive to a 5150 does not make a 5160. They are different in more ways than the existence of the hard drive. In fact you could have a 5160 without a hard drive.

I had an RLL drive that was not spinning. I turned it upside down on the case while troubleshooting something and when I turned on the computer with that drive sitting there, upside down, it spun up and booted to the C: drive! I would try several things you might read short of opening up the drive. Unless you have a proper clean room.

Seaken

Many thanks for the advice : I put the HD upside down and it started and runs ! The PC started and applications are fully operational. I am wondering how we could work with MS Multiplan; MS Word etc. Anyway, the HD works but with some noise from time to time, a one minute period or so (I guess a sort of bearing resonance). In your opinion, how long should I keep it running this way ? Opening it would definitely be useless : risk of dust ingress + no access to the bearings from top (I sew a video).

 

[modem7]

I have a big number of floppies : yesterday I restarted "Multiplan". I am wondering how we could work with that!

The PC started and applications are fully operational. I am wondering how we could work with MS Multiplan; MS Word etc.

Who is "we" ?
And I do not know what you mean by "work with".

Forgot to add something important when its about checking the PSU : the PSU cannot be verified without being loaded. This is very confusing. I lost a lot of time in believing that the PSU was faulty because it was fully disconnected.

Yes, a trap for newbies to the hardware side of the IBM 5150.
That, and some other IBM 5150 basics are at [here].

I put the HD upside down and it started and runs !

... In your opinion, how long should I keep it running this way ?

On the subject, the OEM manual for the Seagate ST-412 indicates, "Recommended orientation is either vertical on either side or horizontal with the PCB down. The only prohibited orientation is horizontal with PCB up." The manual does not indicate why upside-down orientation is 'prohibited'. Could physical damage result? Faster than normal wearing? Data reliability negatively affected? I don't know.

So, maybe periodically, see if the drive starts operating when it is returned to upside-up orientation.

 

[seaken]

That hard drive may not actually be fixed. It is spinning now but that doesn't mean it will continue to run. In my case the hard drive did stop working again. I ended up replacing it with an XT-IDE and Compact Flash card.

Multiplan was a pretty popular piece of software. You should have no problem finding more information on how to use it with a Google search.

Seaken

 

[Svenska]

By the way, not especially proud of being French

You could also list your location as "Europe".

On the subject, the OEM manual for the Seagate ST-412 indicates, "Recommended orientation is either vertical on either side or horizontal with the PCB down. The only prohibited orientation is horizontal with PCB up." The manual does not indicate why upside-down orientation is 'prohibited'. Could physical damage result? Faster than normal wearing? Data reliability negatively affected? I don't know.

I've thought it was because bearing oil could make it onto the platters, destroying data.