So while working on a PhD thesis, I haven't had the time to do much in the retro scene, but I will endeavour to capture what the latest developments are.

For those unfamiliar, the story begins here:
Meet Ol' Bessie
"I'm ready for my close-up now" said Ol' Bessie.

And as a dead-end path I walked, I inquired about SCSI:
Authenticity vs Power

Before deciding to upgrade the graphics, and in the way accidentally snagging myself a prototype Tseng card. Or whatever it is. I'm still unsure:
Tseng ET4000C

And then debating if I stick with it or go OEM with the Advanced Graphics 1024 (I stuck with the Tseng, the OEM is currently safely stashed away):
Authenticity vs Power

And also trying to repair the broken FDD:
Repairing old 3.5" Floppy drive

To begin with, I doubt I could have made it this far if HP didn't still offer the Compaq Diagnostics software for download, you just need to supply your own (size matters here) floppy disk, which I'll link for anyone searching.

720k 3.5":
ftp://ftp.hp.com/pub/softpaq/sp0000-0500/sp0308.zip
360k 5.25":
ftp://ftp.hp.com/pub/softpaq/sp0000-0500/sp0316.zip

So where am I going today? Well I shall hark back to the early days of Bessie, whom I shall call Bessie Mark 1. Bessie mk1 was the computer my dad brought home from work after my continual admonitions that I wanted a computer. Since they were upgrading their line, he got it cheap. Then down the line my friends little brother put in a dodgy 3.5" floppy. The metal jammed inside. It was surgically removed by both my and his mother precision wielding dinner knives. The drive never worked again, "insert system disk or disk error" even when the drive was empty.

So my dad took it into his work to get fixed. It got fixed. it came home. But it was missing the "big drive at the bottom". And the number of kilobytes at the start was 4096 and is now 2048. And my game saves are gone, as are some of my favourite games. And I've never seen these ones before.

But the floppy drive was still broken but now booted. At the time I told myself they'd taken some bits back as they were expensive. No. I was pet turtled. It was a different computer. It took me years to suss this out too 😠. Anyway, the computer brought home shall now be referred to as Elizabeth the Second. Ie Bessie Mk2. Now it is Bessie Mk2 that all my posts have been about, that I've always seen as "my computer". But something was always missing. Summarised by "but the original had that big drive at the bottom". Thus wanting the best of both Mk1 and Mk2, the pursuit for Mk3 began.

Thus racking my brains, trying to recall more than two decades previous, in the memories while I was single digit ages, what tape drive it was. And pouring through old construction and assembly documents, comparing with images found upon searching the part numbers, I think it is the 80/120 MB (1/3 height) 131337-001 DC2080 drive. And as luck would have it there was one listed on ebay as spares and repairs as the seller has no idea how to test tech of this age. And conveniently it even looks like it has the Compaq cage assembly included! Win!

Now as I mentioned earlier, I was attempting to get the FDD working, and I'll be honest, I have no idea why it won't work. I've cleaned the heads, I've greased everything that needs greased. I've cleaned it up with IPA. Nothing. So I realised that I would only be happy with a direct replacement drop in. (Edit: I actually did work out why it didn't work then forgot, one of the tiny hair-thin wires connecting to the rw head is broken, basically unfixable). Partially purism, partially Compaq at this time used a 20-pin setup with an interface board, and most FDDs use 34 pin setup. If the interface board isn't used, i'm not interested. So I tracked down a Citizen OSDA-53B FDD across the pond, paid the $11 + $25 shipping, and got that working. Now why am I mentioning this? Compaq uses card edge connectors for all drives. The triple CE cable Compaq used in this was damaged so I used a replacement with 2 CE plugs. Works fine, but thanks to the previous paragraph, I now need a third CE plug.

Digging out the original cable, I see the sticker on top reading the part number 113594-001G which, according to the spec sheet, is "Diskette/Tape Signal All Diskette Drives 40-/60- and 80-/120-MB Tape Drive" - perfect:

And the actual CE connector is made by Amphenol. Was made by Amphenol. Can find no mention anywhere of these now. Probably a few decades too late.

And the visible damage to the cable:

What surprises me is that pin 1 is a ground. This should have had very little if any effect on the cable. Perhaps I've remembered it wrong and it was always only the FDD that was broken and I've just butchered a cable for no reason. But I have butchered it. Being a purist I want to use as many original bits as possible, so I've ordered a new ribbon cable, and I'm trying to salvage the connectors.

Now let me just say, these Amphenol connectors are *not* designed to come apart again, I've broken 3 of the clips on the first one I removed, and 1 on the second. Hoping I can get the third off pristine. Each leg has a double catch on the outside and both legs need to be pressed simultaneously with a small screwdriver while a third screwdriver slowly turns to separate them at the same side. Fiddly. I hope the image conveys what I mean better than my description:

One other goodie I've managed to find is a memory upgrade for a non-extortionate-price. As I mentioned, Bessie mk1 had 4 MB of ram, which while still a standard issue run, was a higher end version than my 2 MB ram one. The former having a 1 MB memory expansion, which in itself features two additional 1 MB modules, together with the 1 MB on board. Mk2 only has the 1 MB expansion, leaving the module slots empty. The high-end Deskpros however had a 4 MB expansion plus modules. The 4 MB itself was something I'd never seen available anywhere, until I did, additionally featuring two additional 1 MB modules, and bought it for the princely sum of... €30. Since any time I've seen a 1MB module for sale itself it's usually €60+ so I'd say I did well. If it works.

But additionally, I have also realised that the PSU is now over 30 years old as of January. With the same electrolytics. Somehow it still works but I can't trust them anymore, so soon I'll be recapping it, which I'll do in another thread. I know old PSUs don't always have drain resistors across the primary side so can store charge for as long as it takes to be dangerous. Thus I've ordered a 1k 50W resistor to drain them, and will hopefully recap it in polymer instead of electrolytic so I can hope for another 30 years out the old girl.

While I'm here, I'll add some documentation I've found regarding the Deskpros in case it helps another enthusiast.

Manual
http://www.typewritten.org/Articles/Compaq/108033-003.pdf

And these sheets I can't remember where I found them:

386s Config Doc:
https://mega.nz/#!LEIFGawI!m5joFVYntkep58wGPG … 1nH7oChUrpk1Jps

386s Assembly Doc:
https://mega.nz/#!WRAXwQjB!g_Oh_tGaDfbm-7xMyY … y3b-SorAUjlaIpk

386/20 Config Doc:
https://mega.nz/#!3IQjQSiJ!aeO24tkkNMBYHhkiFC … lW-FpHpbPrKceaY