Compaq LTE 8086 repairs

[compaqportableplus]

I've been trying to repair all of my LTEs lately. This is one that I've had for about 5 years, and it had never worked correctly. The backlight on it worked intermittently for a short while when I first got it, and sometimes it wouldn't even POST at all.

This was way before I knew how to solder, so "reapping" it wasn't even an option at that point. Fast forward about 5 years, and I now I am quite handy with a soldering iron! So let's repair this thing!



Fully recapped it, found some broken traces and had to run two jumper wires. One of the traces I found that was broken was close enough together that I was able to just bridge it with some solder. My god this was hard work though, took me forever to find the broken tracks, and man was my back and neck hurting by the time I was done! But it was well worth it in the end!

Now that's one happy LTE!:



Got to fix the sticky bumper in the hard drive, recap and replace the belt in the floppy drive, and it'll be done!

The LTE 8086 is an interesting machine. It was the only 8086 notebook that Compaq ever made. This is also the most compact XT-class machine I own too!

Next one to repair is a Compaq LTE/286 with the same issue! This one should be much easier, as it's probably the same traces that are broken.

Thankfully, I have a spare 20MB drive I can use for now until I can find another 40MB drive. These laptops use a funky 3.5" Conner Peripherals drive that's a little shorter and much thinner than a standard drive with a downsized IDE connector. At some point, I'll build and adapter for it, and then I can use a 2.5" drive! having a 120MB or so in one of these would be amazing. If I did do that, I would definitely miss the unique sound that these drives make though!

Really glad that the LTE and LTE/286 were the only LTEs to use electrolytic caps on the motherboard! The LTE 386s/20 and onward are all-tantalum on the system board. Really makes life easier! This 8086 is all-tantalum now though

 

[compaqportableplus]

Another interesting observation I have made with these machines is that both this LTE and one of the LTE/286s I have appear to have had their serial number stickers pulled off and reapplied before. The very earliest LTEs and LTE/286s were made out of a different kind of plastic, which can be identified by having a more "shiny" appearance, and the "Power" and "Standby" embossing is written in a much larger font. The one thing I have observed with this plastic is that it shatters like glass! I have one that is made out of this earlier plastic, and it's too far gone to save, so I have been using it for parts.

I believe that Compaq was probably replacing these early casings on these at no charge due to the fragility of the plastic. Another thing that makes me think this is that the production dates on the system board on this machine are early 1990, and I found a 1992 year stamp on one of the plastic parts in this LTE 8086.

 

[compaqportableplus]

Got the LTE/286 done! Boy this one was a lot of work!



Think I spent 5 or 6 hours total on it! Took a while to track down where some of the broken vias connected. There was also a tiny ceramic cap that was completely rotted from cap goo that I had to replace! It fell to pieces when I removed it!

Currently installing MS-DOS 6.22 on it!

 

[compaqportableplus]

Thankfully, I have a spare 20MB drive I can use for now until I can find another 40MB drive.

I guess I removed the rest of this story on accident.

The LTE/286 that I just got done repairing had the 40MB hard drive which is a little harder to find than the 20MB version. I was fixing the sticky-bumper issue on the drive, and while I was screwing the magnet back down, my screwdriver slipped and gouged the platter. I feel pretty ashamed of that, as I have repaired many Conner drives successfully in the past. Mistakes happen! Still pretty pissed about it, but it is just an old hard drive at the end of the day Should have been more careful as close to the platter as that screw was, but I definitely learned from my mistake, and it won’t happen again.

So for now this machine has a 20MB drive until I can obtain another 40MB one.

 

[compaqportableplus]

Just a quick little update on the LTE/286; I have now replaced DOS 6.22 with Compaq DOS 3.31, as DOS 6.22 was taking up way too much room on the 20MB drive, and wasn’t really letting me do anything I couldn’t do with Compaq DOS 3.31. Plus this is the original OS for this machine, which is very cool.

Now I’ve got room for Windows 3.0 and some other cool stuff!

 

[compaqportableplus]

The hard drive is now fixed in the LTE 8086! Here's some shots of it running:





It's running the copy of Compaq DOS 3.31 that was already on the drive, and I installed Windows 2.03 along with some other things. It appears the this machine was last used in around 1997! It would've been already quite old by that point.


Here's some shots of CheckIt running on it:





Scores 2.74 times an IBM XT. Pretty sweet.


Here's also some pics of the CPU board:





You can see the OKI 80C86 CPU, and also notice where the board says "ORION I PROCESSOR". I would say "ORION I" was probably the code name for this machine, and the LTE/286s I have say "ORION II" inside of them. So "ORION" was likely the code name for the original two LTEs.


I also need to refurbish the floppy drive (new belt and caps). To get software into this machine, I actually had to use LapLink Pro's "remote install" feature, which lets you install the program on the remote computer from the serial port! I usually use FastWire II (similar to FastLynx 2, but doesn't have the remote install feature), because it's a much lighter program. LapLink Pro runs very slowly on my IBM PCs and XT (this 1991 version does anyways), but for newer systems it's fantastic.

 

[rimmeruk]

I also need to refurbish the floppy drive (new belt and caps). To get software into this machine, I actually had to use LapLink Pro's "remote install" feature, which lets you install the program on the remote computer from the serial port! I usually use FastWire II (similar to FastLynx 2, but doesn't have the remote install feature), because it's a much lighter program. LapLink Pro runs very slowly on my IBM PCs and XT (this 1991 version does anyways), but for newer systems it's fantastic.

Great post! I know this is a bit late posting but have you ever used MS-DOS's INTERLNK.EXE and INTERSVR.EXE ? They are very lightweight and are quite fast for transfering
files using the virtual drives that are created. AFAIK it can be used with Serial/Parallel cables and a Null modem setup.

I purchased a copy of Norton's PC Anywhere just to get the transfer cable that's included in the boxed version. It's a very high quality yellow parallel port2port cable.

 

[compaqportableplus]

Great post! I know this is a bit late posting but have you ever used MS-DOS's INTERLNK.EXE and INTERSVR.EXE ? They are very lightweight and are quite fast for transfering
files using the virtual drives that are created. AFAIK it can be used with Serial/Parallel cables and a Null modem setup.

I purchased a copy of Norton's PC Anywhere just to get the transfer cable that's included in the boxed version. It's a very high quality yellow parallel port2port cable.

Thanks! Yes, I use interlnk and intersvr all the time as well. It’s really cool for machines that don’t have hard drives, as you can link it to another PC and use its hard drive as if it were in the machine! What’s also great is that those programs will work in much older versions of DOS also (at least back to 3.30).

I have a copy of LapLink that cam with a similar yellow cable, as well as a blue serial cable all in one box!

 

[RetroHospital]

I am myself repairing a LTE 286 and face the hard disk problem
The thign "works" (posts, complains about battery, etc) the backlight blinks a bit but I guess this needs a recap.

Before even thinking of recapping it, I just can't live with the conner hard disk situation...

Did anyone ever create an adapter to be able to put an IDE CF adapter on those ?
Or did I just buy the most impossible to repair laptop ever ( opening it is already a challenge)

I understand this is realy a sub sub niche so I don't have much hope

 

[compaqportableplus]

I am myself repairing a LTE 286 and face the hard disk problem
The thign "works" (posts, complains about battery, etc) the backlight blinks a bit but I guess this needs a recap.

Before even thinking of recapping it, I just can't live with the conner hard disk situation...

Did anyone ever create an adapter to be able to put an IDE CF adapter on those ?
Or did I just buy the most impossible to repair laptop ever ( opening it is already a challenge)

I understand this is realy a sub sub niche so I don't have much hope

I believe the pinout of the connector is the same as 2.5” IDE, but I honestly don’t know for sure.

If you take care of the sticky rubber bumper in the original Conner hard drive, it will be far more reliable than you might think. Aside from the one I accidentally trashed, all of mine have worked great.

Definitely want to recap ASAP! The leaking caps are slowly rotting the traces away right now.

 

[RetroHospital]

Well the drive seems to use an extremely exotic connector with two flat flex cables piled up on top of each other
Quickly looking at the situation, there is no way to ever create an adaptor for those.

I own a variety of laptops and all of them now run some kind of compact flash, it would be quite a failure for me to not be able to do the same with such an iconic laptop. I see this as a way to make sure they still work in 10 years... And to make them more usable and appealing when displaying them like in computers fairs.

At this stage, looking at the thing, the only thing I can realistically think of is maaaaaaaybe to hand solder each and every wire directly from the motherboard to a CF adapter.
this would be tedious, probably hours of work , but less then consuming than designing a PCB that just seems impossible to do from flat cable with very unpredictable results.

If I could at least confirm the pinout of that conner drive - is there any tech documentation that would go this deep ?

 

[compaqportableplus]

Well the drive seems to use an extremely exotic connector with two flat flex cables piled up on top of each other
Quickly looking at the situation, there is no way to ever create an adaptor for those.

I own a variety of laptops and all of them now run some kind of compact flash, it would be quite a failure for me to not be able to do the same with such an iconic laptop. I see this as a way to make sure they still work in 10 years... And to make them more usable and appealing when displaying them like in computers fairs.

At this stage, looking at the thing, the only thing I can realistically think of is maaaaaaaybe to hand solder each and every wire directly from the motherboard to a CF adapter.
this would be tedious, probably hours of work , but less then consuming than designing a PCB that just seems impossible to do from flat cable with very unpredictable results.

If I could at least confirm the pinout of that conner drive - is there any tech documentation that would go this deep ?

I’m really not sure if there’s any documentation with pinouts for these drives out there or not. It is definitely some form of IDE though, so an adapter should theoretically be possible.

There were 4 models made in this series of Conner drives, the CP-4021 (Compaq OEM), CP-4041 (Compaq OEM), CP-4024 and the CP-4044, so that’s the drives you can search for pinouts on, as they all use that same connector.

I generally use the original hard drives in my systems, so I really don’t have much experience with the CF adapters.

Definitely wish you luck on getting it worked out! Would love to see the end result if you do figure it out.

 

[RetroHospital]

oh believe me I’ll figure it out
I always have half a dozen of half finished projects ; but I always finish them .

What I’ll do is to first use 44 breadboard wires and try to squeeze them in the connector - between a cf adapter and the motherboard

Of course I’ll first check that it roughly matches ide 44 standards ( like check the grounds are where they are supposed to be ) and then hope for the best as I can’t possibly individually check each pin

This might end up in a disaster but oh well

If that works at all , because even if the adapter works ; some 286/386 era bioses just can’t use compact flash - although I do have a compact flash in my 386SLT after much tweaking and a very special type of card - so I have good hopes .

If all of that works — I’ll maybe invest some time designed a basic pcb ; basically a dotpitch adapter. I’m not sure someone else would be interested .
I’m often feel I’m the only guy on earth repairing laptops …

 

[Mike Johnson]

oh believe me I’ll figure it out
I always have half a dozen of half finished projects ; but I always finish them .

What I’ll do is to first use 44 breadboard wires and try to squeeze them in the connector - between a cf adapter and the motherboard

Of course I’ll first check that it roughly matches ide 44 standards ( like check the grounds are where they are supposed to be ) and then hope for the best as I can’t possibly individually check each pin

This might end up in a disaster but oh well

If that works at all , because even if the adapter works ; some 286/386 era bioses just can’t use compact flash - although I do have a compact flash in my 386SLT after much tweaking and a very special type of card - so I have good hopes .

If all of that works — I’ll maybe invest some time designed a basic pcb ; basically a dotpitch adapter. I’m not sure someone else would be interested .
I’m often feel I’m the only guy on earth repairing laptops …

How did you go with this project? I'm keen to run a CF adaptor as well instead of the Connor drive.

 

[CSTThor]

Did anyone ever manage to get a CF image working, I've spent hours and hours trying to make a Type 2 image for the 20mb Conner, but while it boots and works fine on other laptops it will not work on the LTE 8086, it always refuses to recognize the drive. Sadly both Conner hard drives I have are too faulty to generate a disk image from. either a 20mb or 40mb image would be great.

 

[ajacocks]

Welcome to the forum @CSTThor !

- Alex

 

[Mike Johnson]

How did you go with this project? I'm keen to run a CF adaptor as well instead of the Connor drive.

Can I ask a a favour? Is someone able to PM 'RetroHospital' to come back to this thread?

Really curious if the project got done, Thanks in advance.

 

[RetroHospital]

Well I have good and bad news

I did not need to design a PCB adapter, there is an aliexpress dot pitch adapter that requires very little modification to basically fulfil what is needed here. I've got a couple of those in my stock now.

But the bad news is that I don't have the Compaq LTE anymore to test it with, as it had multiple other issues - it was impossible to salvage, and wouldn't make it possible to tets my HD replacement as the motherboard didn't boot at all...

I'm waiting to find a better unit to revive this project (to test it). I'll try to post a picture of the connector in the meantime.

 

[RetroHospital]

@CSTThor as I just said above I wasn't able to get that far with my own LTE286 repair but about such old laptops refusing to boot from CF, especially if they HANG with a CURSOR at boot, this could be caused by your CF only supporting LBA era and not CHS, or reporting itself as a removable media (or both).

This can be SOMETIMES be "solved" by either using "industrial" CF cards (they are often 5x more expensive than regular card and of reduced size, like 512MB max). You need to carefully read the PDF specs to be sure. Your CHS BIOS needs to be "tunable" enough to roughly match the card's specs, I think only the head and cylinder count really matters, as long as it makes a "virtual" drive that is smaller than the physical one (eg 48MB CHS settings on a 64MB CF drive).
Or SOMETIMES by using a special disk partitioning tools that zaps the MBR at the lowest level and allows to go beyond BIOS int13h limitations (I'm not going into details that I don't fully understand myself). In the US people often use Ontrack Disk Manager (like Version 9) but I'm using a very light german tools that does the same, and boots with a popup multi boot menu. (I'll need to look up the name as I havent played with it recently.) This allows not only to boot but to have multiple 32MB partitions, and solve other problems.
And SOMETIMES the vintage PC simply refuses to talk to anything but the real hardware. This is especially true when these were shipped with HD of very specific sizes, and have no drive BIOS settings. However settings or not, this is still IDE in the end, so if the CHS settings of the original drive (here the Conner 20) falls into the specs of a specific industrial CF, you might still get a chance. (eg Conner 20 probably has the same headcount as a 32MB industrial CF, and the cylinders don't really matter as long as they are less than what the CF supports)

I'm not sure in which situation the LTE8086/LTE286 falls as I havent done this myself on that specific unit, but what I just described allows other similar laptops to boot.

 

[Mike Johnson]

Well I have good and bad news

I did not need to design a PCB adapter, there is an aliexpress dot pitch adapter that requires very little modification to basically fulfil what is needed here. I've got a couple of those in my stock now.

But the bad news is that I don't have the Compaq LTE anymore to test it with, as it had multiple other issues - it was impossible to salvage, and wouldn't make it possible to tets my HD replacement as the motherboard didn't boot at all...

I'm waiting to find a better unit to revive this project (to test it). I'll try to post a picture of the connector in the meantime.

Thanks for the update RetroHospital.