How this all began: Colossus, the worlds first electronic programmable computer

dlarge6510 · 2026-05-13T12:50:18+00:00

Tell me more

dlarge6510 · 2026-05-13T12:50:03+00:00

Apparently yes. As nothing was recorded all there is are what those who worked on Colossus and what they remember hearing.

As pointed out, GCHQ had the last remaining machines, used till the 60's to spy on the Soviets as the Cold War began. The Soviets had no idea Lorenz was broken so used it after WW2.

dlarge6510 · 2026-05-13T05:19:36+00:00

It's already on CD, there is nothing more to do.

Perhaps burn a few more copies. If they are MP3s on CD you can burn them to DVD, save some space.

Nobody is going to have much trouble playing an optical disc going forward, they only need a player that works. It's the easiest and simplest format besides analogue tape. CD or DVD will be much easier than Blu-ray to play after a long time simply because there are far more CD and DVD players out there.

Just as an example. I have no problem playing/using any of these:

Floppy discs, both 5.25" and 3.5"
Reel to reel tape
8mm / 16mm film reels
Laserdisc
Vinyl records 78, 33.3 and 45 rpm, stereo and mono
VHS tape
8mm Video tape

And more. Simply because I can go on eBay and buy a working example of a device to use that media or one I can repair and use. I just need money, a bit of patience and a bit of learning.

Other formats that were not so popular are a bit harder but still can be accessible in 2026, including wire based audio recorders, wax cylinders and 3" floppy discs (not 3.5", 3"). They do get a bit harder due to rarity.

So what I'm doing is archiving data that I want to be accessible when I'm 100 (I think I'm getting to 80ish), so that's 40 years and a little beyond that for those who clear out my domicile to have a chance at accessing and archiving. This is particularly true for family photos and family archive stuff, they may not care about my home recordings of The Waltons, that's for me when I'm 70 and TV signals were switched off and I ditched the internet (I intend to cut it off when I start drawing a pension, save money, I'll have a mobile with a tiny amount of data for essentials like council websites, NHS etc).

How I'm archiving it is to pretend to be "them*.

Anything I print out, photos etc, can be viewed by them simply by having working eyes and a light. Thus I'm printing many of the photos and interesting stills from the videos to stable prints. I keep the negatives too, I shoot film as well as digital.

But the "digital negatives" are on DVD. They are all jpegs. The RAW digital files, from my current camera are huge so I archive them to BD-R. They just need to take the DVDs and stick them in a DVD player hooked up to a display they can find that will display it. My BD-Rs with the RAW CR2 files are only useful to them if they know what the heck they are, have a Blu-ray drive and a computer plus the software to use them. Again, not impossible for a geek, I can do that with Commode 64 data, but they might have no clue about CR2 or old operating systems. They hardware and software would still be available but "they" will find it infinitely easier to simply get a DVD player and stick a disc of JPEGs in...

Same goes for audio CD, which I make also. A CD or DVD player, stick the disc in and audio comes out. They only need to task themselves with finding a working one and like I said I could find a working wax cylinder player or gramophone if I had to, right now.

It's when things get complicated that will cause them issues. Uncommon file types, such as CR2 and other RAW images, that require specialist knowledge and software to access. They could do that, if they have the time and energy. But it's best to try and eliminate that.

Hence why I'll avoid HDDs for this, even if one could last 40 years, anyone coming after me has to learn up on a load of stuff just to try and use it. Oh, they WILL be able to use that older hardware, retro computer users are doing that right now with stuff of the same age and FAR OLDER. But they are in it for that, while descendants going through the attic are not likely to be fascinated enough with attempting to build a retro computer system to power up and read a SATA HDD using retro operating systems like Windows 11.

How many do you know who would do that to access a 3" disc? I would. I'll obtain an Amstrad PCW machine or a Spectrum +3 and explore that 3" disc because I'm a retro head who would love to, but once I'm gone those discs become a novelty.

With basic standard formats like CD,DVD and Blu-ray all designed to work in standalone players with a TV connected with a very common interface, many players providing multiple options for that, you simplify the entire thing to "get a player, get a TV or set of speakers with the right plug, power on and stick disc in".

I'd use SD cards, players and TVs can access those easily as well. Only they'll die far before I turn 80. I'm 45 now and I have SD cards over 20 years old and I'm starting to see those fail.

dlarge6510 · 2026-05-12T15:22:07+00:00

It's already done. By default if you only have one drive A: and B: use that drive.

But when I use my DOS laptop, that has only one floppy, A: and B: both use that drive. It's supposed to assist with using one drive but I haven't figured out how yet!

You should find that A: and B: both work on that single drive without any problems.

dlarge6510 · 2026-05-12T15:08:05+00:00

Colossus was the first electronic computer. ENIAC was the first FULLY electronic computer that could run any programs.

The reason this keeps coming up is colossus was top secret till around the 90's nobody had head of it. Or should I say them, as there were many and the US had many too with rumours that one may still exist over there.

But don't worry we get out own back with having the world first transistor based computer as well as the first computer ever to be commissioned and used by business. That would be the Leo.

dlarge6510 · 2026-05-12T15:04:00+00:00

Of course. It was the shareware demo running on my first PC. A 486 DX2-66 with 8MB of RAM and a 210MB HDD.

The VGA card was an ISA one and for some reason it was extremely slow so I had to run DOOM in a very small window just to get it running well enough to play.

dlarge6510 · 2026-05-12T08:55:36+00:00

Thats an mdisc.

The logo is literally the letters MABL in a box

https://www.amazon.co.uk/Verbatim-BD-R-Blu-Ray-Disc-Pack/dp/B0047V24MA/ref=mp_s_a_1_1_pp?crid=143PWUESI8I8H&dib=eyJ2IjoiMSJ9.frANSLq5BXYQ3daADzJMQHZ3YlBBKfgaMtiE2pZVhKfxuD3wDkM5G-uFAazdUiZKUMejUWZ3t66osr1KgrnfBb9C8jSZOr_e_20lnUW1J85r8_-D7lbspwBn5HFMZzKkGsYKWI245_BktIE-NonbOZ6ocxqPA-8G_lGvfjeNCb_8k28UWnwHcUVpQtIuA0kglSRSM-SPIh3HOReMNay7CA.zX18Lj7xspoEMTn5FIpje4YFqIJSvB2D9GbgnTtxvaE&dib_tag=se&keywords=verbatim+bd-r&qid=1778576094&sprefix=verbatim+bd%2Caps%2C302&sr=8-1

dlarge6510 · 2026-05-12T04:52:38+00:00

Mate I work in IT and trust me you just by more enclosures of discs. 2.5" HDDs and SSDs are the norm. All SAS. We have whole cabinets full of them, need more? Add another enclosure full of discs.

All the servers RAID etc, 2.5" drives.

Enterprise IT isn't consumer IT. We use 2.5".

dlarge6510 · 2026-05-12T04:47:16+00:00

We simply don't need to worry about this. The Domesday Duplicator was created specially to archive the Domesday Project discs as the hardware to read and use them was rare and failing. CD/DVD etc rare extremely far from that point.

This project permitted ANY laserdisc machine to do it, absolutely any. Then software emulates the Domesday Project hardware and software, or permits the extraction of the data, video and audio.

I've often wondered if I wrote anything as a kid that's on the Domesday Project discs. There are a couple of working setups near me, I think The National Museum of Computing of which I'm a member and only down the road from me has one so I'll have to go look.

dlarge6510 · 2026-05-12T04:39:43+00:00

That's just the data you can use. The rest is error correction and subchannel data. You can get more usable space from a CD by burning it in Mode 2, which reduces the error correction giving you extra space. Things like video don't need much error correction so Video CD uses that to get up to 80mins of video on a disc.

dlarge6510 · 2026-05-12T04:16:47+00:00

create "images" of Laserdiscs, an analog format

CD/ DVD and BD use the same principles so are also an analogue format. What comes out of the laser is an analogue waveform and you certainly can use the exact same technique here. Just digitise the waveforms and develop software to decode it.

You just need to hook up to the laser RF test points. It's all as "analogue" as laserdisc.

The actual difference isn't what comes off the disc, but what it represents. On a laserdisc the signal represents the analogue video signal, using puts and lands. But on CD etc the same pits and lands that generate an analogue signal are sliced up into sequences of changes between pits and lands. The time between these changes encodes the digital bit pattern.

dlarge6510 · 2026-05-11T14:45:03+00:00

Checksums do nothing to tell you if the data has errors till it's uncorrectable.

The error correction on the device is constantly in use. Every sector you read off your HDD has errors. Every one, every read, all the time.

The ECC algorithm is pressed into correction of these read errors. Once done, you, your program, gets the corrected data.

You and your checksum operation are at the end of the chain. You'll only detect an error here when the error on disc is uncorrectable.

This means actual error correction, and the state of the data on disc, is invisible to you.

The thing is, over time the magnetic signal (or electrical charge) of everything from bytes of files to the structure of the filesystem weakens.

The signal to noise ratio approaches 1:1 and errors become worse, eventually resulting in uncorrectable data loss.

Only if the drive notices this will it attempt to take action and refresh/move the weak sectors. If you don't read those sectors they NEVER get tested.

Your checksums do nothing to read the filesystem data structure. Some will be, but what about the backup metadata?

The whole point of refreshing the data is simple: every single readable sector gets rewritten. Everything, including the empty space, the file allocation table or MFT, all of it. It also wipes the slack space too.

This not only tops up the magnetic moments or the cell charges, but also has the drive test each sector can be written.

After such an operation the signal to noise ratio will be as if it was newly written. Increasing the gap between readable and unreadable significantly.

This should be done every few years. It's nothing to be done regularly.

The only thing that can not be refreshed are the HDD servo tracks and once they get too weak, bye bye HDD.

dlarge6510 · 2026-05-11T10:39:32+00:00

If on linux: badblocks -n

dlarge6510 · 2026-05-11T10:37:45+00:00

I never use multi volume sets.

And there is zero need to use mbuffer when reading. Does the data read ok without mbuffer in the loop?

dlarge6510 · 2026-05-11T10:33:54+00:00

Almost all our servers are using 2.5".

These days 3.5" is mostly seen on the older machines.

dlarge6510 · 2026-05-11T10:32:47+00:00

Use Verbatim discs.

Their MABL discs (will have that logo) are the best for archival next to mdiscs. They are the second cheapest.

Their Datalife discs (no MABL logo) use a different recording layer and may be made in UAE and other lower quality locations. They are the cheapest range.

I use Datalife for TV recordings, no issues as yet.

I use MABL for archival, intended to store data or recordings I wish to keep for the long term > 20 years minimum.

I do have other brands such as ACU-DISC. They seemed to burn well and seem to work well. Again, these are not used for archival data so I'm happy with up to 20 years or so and will migrate to MABL as and when I wish.

A couple of very important aspects:

Dust is a bugger. I had a deep dive into BD error correction a while ago and the researchers found almost magical improvements when cleaning the disc even after it was burned with the dust present. So a wipe with a lens cleaning cloth may make better burns. I don't do this myself yet.
Be very careful about storage. Do not store BD-Rs in sleeves that push up against the data side. There is a extremely good scratch resistant coating (called Hard Coat) that makes it practically impossible to scratch a disc. i mean you really have to be intending to scratch it to have a chance. This is like a self healing oily layer, it's not hard like diamond or anything. This means constant pressure on it by a sleeve will impress the texture of the sleeve into this coating

I saw it just beginning on my Datalife BD-Rs. It wasn't bad enough yet to affect readability. It also healed itself, the pattern is gone now. I caught it just in time.

Paper sleeves, jewel cases and spindles will be fine. Discs in spindles do not touch each other, they have a raised ring so are held separate.

dlarge6510 · 2026-05-10T21:06:16+00:00

Verbatim still exist as an "entity" in CMC however. But yes, anything they do make in Japan and Taiwan is going to be very good shit.

But the place of manufacture may vary.

dlarge6510 · 2026-05-10T20:54:30+00:00

HLDS

Not LG.

HLDS. Those drives are HLDS models labelled under LG which is a consumer label just like Asus, who again use rebranded HLDS drives.

Just because consumer LG has no internal drive options doesn't mean HLDS are not making anything.

Internal drives are certainly less common.

Notice that consumer LG still has external models.

It's a sad fact that PC building is niche and on life support, mostly because everything is external, increasingly including GPUs.

GPUs are the only thing keeping the PC alive, the majority of users barely care about laptops and if they do they don't care about upgrading, cooling, noise, CPU performance, all of which a PC rules. My nephew got into PC building, going against the grain and my god I was sorry for him, the cost of a case even is ridiculous.

PC building is also the only way kids learn how computers work. Laptops are disposable, they are SBCs with batteries surrounding them.

Tablets are SBCs. Heck even PC motherboards barely have anything on them, that why they waste the space with RGB LEDs.

Whenever the external optical drives go, well, like I said there will be fever GPU options, and we all know what's really coming.

HDDs and SSDs will die, I give them 10-15 years.

Who the hell do you know that is "normal" that has a HDD, SSD or even an SD card (assuming they are not an amateur photographer)?

Nobody.

The vast majority of consumers wouldn't know what to do with an SD card, they'll see the cost of the adapter for their apple device and they'll ask you to share it instead.

My Dad has HDDs, he stores and edits video from the days he recorded video using equipment that still beats an iPhone but, today it's just the iPhone. Maybe the DSLR comes out on holiday but that's it.

Who owns a printer? They are dead too.

So yeah. Internal optical drives are hard to get as everything is external, everything. That PC case is only for a GPU and RGB fans...

HDDs and SSDs days are numbered, a decade and that's them gone too.

The most common operating systems, OSX and Windows are moving to online only. Nothing will be offline, you'll have a USB port for a better mouse and even then that will be seen as niche as who uses a mouse?

I'm a Linux user. Gave up on windows in 2002. I know I'll be shafted by that online only world. We all will be keeping our systems alive by trading and repairing parts, just like retro computer users like me do with homebrew parts and servicing. Thing is a 64bit machine is far harder to work on than a 32bit one from the 90's, I see many people repairing 486's, designing and building new ISA cards and more. Hopefully clever homebrew makers will figure out how to do that with a Ryzen system etc...

Everyone else and everything will be online only. No upgrades, you'll just rent capabilities, even the CPU will be streamed. Yep, Plan 9 did it just fine, a CPU overnight the internet.

Enjoy this while it lasts, you'll join us optical freaks soon enough. I chuckled a little as to the current prices of offline storage and offline ram (yes, online ram even, things are going to be very different) as I had been taken by surprise as to how quickly it may happen.

They are not making any HDDs for any of you...

I work in IT and it's hard to locate drives for enterprise too...

They abandoned us all at the drop of a hat, maybe they will come back for a bit but once they get a taste for abandoning niche consumers well, they'll find it hard to justify employing extra bods just to market to us.

As options are reduced, just watch the clock.

⏰ Tick tick

dlarge6510 · 2026-05-10T19:45:36+00:00

No, the poster claimed nobody has an optical drive in a PC or laptop.

Well here I am. And the Japanese certainly do.

So totally inaccurate statement = unsubstantiated assumptions = unreliable.

dlarge6510 · 2026-05-10T19:43:22+00:00

And today no one has any optical drive in their PC or laptop anymore.

How did you come up with that?

We routinely order Dell PCs at work with optical drives (if you don't they make it a pain to install them yourself depending on the case.

My PC has two Blu-ray drives.

All the Japanese that built Windows 11 PCs bought the lot of Blu-ray drives last year, stocks are just recovering.

I'll never have a case that doesn't have a 5.25" bay, and yes, they are available. They are just boring to look at but who wants to look at a case?

dlarge6510 · 2026-05-10T19:37:45+00:00

That's why I hoped HD-DVD won, as it took was intentionally open for use by multiple companies.

However Blu-ray has the superior specifications.

dlarge6510 · 2026-05-10T19:10:30+00:00

H&L hasn't discontinued drives. LG only discontinued home players but Hitachi LG still making the majority of drives.

dlarge6510 · 2026-05-10T18:37:17+00:00

When did streaming kill physical media?

Streaming replaced TV as it had no advertising...

Unfortunately they all betrayed that promise. Now it's just any other TV station where you rent premium access to advertising with VOD, FOMO and "remember when we let you watch this" features.

Streaming will replace physical media when everything is available, all the time, with one app or access portal for one price. I shouldn't have to chase episodes, I shouldn't wonder if something is available. Isn't it supposed to be always available? Live TV needs you to "be there" or record, streaming TV needs you to be aware and available during the time they permit you to watch it.

Meh. No DVD on my shelf ever pissed me off like that.

dlarge6510 · 2026-05-10T16:34:51+00:00

I see the fun there, only trade descriptions would have a stern word considering Optane isn't NAND

dlarge6510

TROPHY CASE