Phil M0OFX

Software preservation | electronics | software dev | ham radio | a maker of things!

Pronouns: https://pronoun.is/he/him

<philpem> the ionosphere doesn't care what your callsign is

Current projects:
#Datatrak radio navigation
DIY #AnalogCable TV headend
Software preservation (#DigiPres)
Silicon chip photos (#ICRE)

🏳️‍⚧️ Trans rights are human rights
💬 Opinions are my own

ham callsign: M0OFX
github: https://github.com/philpem
website: https://www.philpem.me.uk
backup account: https://oldbytes.space/@philpem

Public Key

npub1pu6x6lz9s8n200v758szpztnkq94nrnl55c5ujmhx3ul4arcvqjqmwp73t

NIP-05 Address

[email protected]

Profile Code

nprofile1qqsq7drd03zcre48hk02rcpq39emqz6e3el62v2wfdmng70673uxqfqprpmhxue69uhhyetvv9ujumt0d4hhxarj9ecxjmntc5ud3m

Publishing to

relay.momostr.pink

Author Public Key

npub1pu6x6lz9s8n200v758szpztnkq94nrnl55c5ujmhx3ul4arcvqjqmwp73t

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Last Notes

2026-05-29 13:38:33 UTC

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"If I can shoot rabbits, I can shoot fascists "
https://digipres-club.s3.bhs.io.cloud.ovh.net/media_attachments/files/116/658/136/741/081/922/original/1118c6d05e3eae77.jpg

2026-05-29 12:38:27 UTC

Somehow given the choice between a museum with Omg Dinosaur Bones and one on the history of democracy, queer rights and trade unions, I've picked the latter.
Walked in to a display on LGBTQ activism so I think we're off to a good start

2026-05-01 22:38:16 UTC

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emacs user sighted

2026-04-01 23:06:01 UTC

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they have a launch trebuchet at Cape Canaveral now?

2026-03-31 09:53:06 UTC

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I would take low-tripping as more acceptable than what the rotary-turn ones do -- locking on.
Re fusing down, I'd take a look at the IET Regs section on load diversity and see if that affects your numbers.
How much current does the inverter need? Is it practical to take its fuse and the charger fuse right off the busbar then take a cable to an MCB box via a service fuse?

2026-03-31 08:47:23 UTC

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For the HC runs to the subs, I'd probably fuse to cable rating less a 20% safety factor. Then the breakers can be whatever they need to be.
I'm cautious about DC breakers, the rotary Chinese ones are terrible. I'd want something name-brand. Metal enclosures too. Couldn't find a source when I did it. Still running my Jeanmuller 160A switchfuse.
If it's engineered right, the fuses are your Hail Mary and you shouldn't lose a HC bus fuse at the same time as a circuit fuse. But keep spares.

2026-03-31 08:43:43 UTC

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I don't think I ever blew a fuse on my solar DC system. My way of dealing with the blowing problem was to keep a couple of spares on hand.
I'd probably have a master high-current fuse panel near the batteries - solar, inverter, and a couple of lower-fused circuits for sub-panels.
I'd probably go with one SP for appliances (powerpole oulets, fridge, CPAP socket).
Put the infrastructure on another one (fridge, HVAC, water, LAN).

2026-03-23 18:54:29 UTC

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Grrr that's not Badr, it's Astra 2G. That constellation is loud enough that it's nearly impossible to align the dish without a spectrum analyser.

2026-03-23 18:21:35 UTC

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Badr is colocated (ish) with Es'hail 2, so I'll take that for a test run.
https://digipres.club/system/media_attachments/files/116/279/875/155/945/000/original/ad07de86ffaefc13.jpg

2026-03-23 14:39:52 UTC

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Hi there Astra!
https://digipres.club/system/media_attachments/files/116/279/003/523/781/243/original/a56f4ae22bc705ed.jpg

2026-03-23 12:30:01 UTC

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I'm pretty sure that's not checked the Network ID.
https://digipres.club/system/media_attachments/files/116/278/492/493/311/190/original/ab772aee1d41d1b8.jpg
https://digipres.club/system/media_attachments/files/116/278/492/799/253/423/original/3d7f44676f6861ab.jpg

2026-03-23 12:26:56 UTC

Well that'll be why I can't find the Es'hail 2 beacon That's Hellas Sat 3. I turned the dish the wrong way.... Es'hail 2 is south of Astra 2. Buuuhhh
https://digipres.club/system/media_attachments/files/116/278/475/700/286/559/original/4aeed812a6c96734.jpg

2026-03-22 19:59:25 UTC

You ever had a curry which was so good you don't mind the 45 minute wait for the train home?

2026-03-20 02:17:38 UTC

Wow. I'm literally on my way to bed, and @npub13hr…833j Britsniped me.
(Britsniping: when you say "Postman Pat" and the theme tune pops into the heads of all the Brits listening)

2026-03-15 22:00:55 UTC

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I guess maybe the problem isn't so much bsky as people who are so used to being treated like crap that someone saying "u a good egg, attaboy" and meaning it may look like manipulation or at least insincere

2026-03-15 21:59:49 UTC

Only on Bsky can you post "I wish the event all the best, I'm glad the mistakes have been acknowledged and learned from -- and also shout out to X, Y, and Z who are real hoopy froods" and get attacked for it...

2026-03-02 19:25:28 UTC

This sounds as legitimate as "Legitimate Technical Services" or "Flowers by Irene".
https://digipres.club/system/media_attachments/files/116/161/215/946/214/060/original/860f11cde4578ad0.png

2026-03-01 03:21:01 UTC

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"Shame he didn't realise the silence was disbelief not respect."

2026-03-01 03:17:27 UTC

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"Shame he enforced the rules and not the spirit. Lots of authority and chuff all discretion."

2026-03-01 03:16:47 UTC

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"He's great at handling problems with confidence, but not so much judgment."

2026-03-01 03:11:15 UTC

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OH: "[That project] was a bold new horizon, shame the Post Office and Fujitsu built it." (savage, I love it)

2026-03-01 03:09:50 UTC

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"Very agile, but the release train hit the buffers."

2026-03-01 03:07:07 UTC

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"He fixes his car like he writes his code. By the way if he offers you a lift, say no."

2026-03-01 03:05:32 UTC

"If confidence was torque, he'd have no drivetrain left."

2026-02-25 13:56:35 UTC

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IKYKAIKT, but what is it about blue huskies?

2026-02-25 09:05:41 UTC

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Quick nap after dinner, and then it's the following morning?

2026-02-18 01:48:03 UTC

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Now that's interesting, I got into the habit of asking Claude to cite its sources and use Harvard references and web links - which I guess is similar.
I can't see the memory feature, is that a paid one?

2026-02-18 01:39:01 UTC

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(6/6)
They're tools and they have limitations. "Make me a quick web interface for this database" works okay because it's a cut-and-paste problem.
There will be bugs (especially security ones) in the code. You will have to find and fix them.
Imagine a new eager-to-please intern at their first job, deep in culture-assimilation and Dunning-Kruger. That's the nearest human analogy I have for LLM's "way of thinking" (airquotes).
And I still have major objections to the amount of resources they use.

2026-02-18 01:32:23 UTC

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(5/6)
GPT seems to do better if you ask it to review documents, or "review the tone and language of this document".
I've chucked in conversations from public spaces and it's pointed out things like "these two people are arguing past each other - here's A's position and here's B's". That's been helpful, especially where I was one of the participants. At least it highlighted a bias in myself I needed to be aware of.

2026-02-18 01:26:14 UTC

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(4/n)
The more interesting one to me is language.
If you try to use GPT as a therapist (ask it for advice) it has a really nasty trend of agreeing with everything you tell it. I would say it's pretty dangerous. Some of the things it's suggested to me were scary enough I deleted the chats entirely.
If you try to use Claude in the same way, I've found it bombs out and gives you numbers for human therapists and support services. Much better outcome.

2026-02-18 01:24:47 UTC

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(3/n)
I've tried ChatGPT and Claude.
I've found GPT terrible for coding, it seems to rewrite huge chunks of code on every interaction. Claude is much more restrained. But I'd still tell it explicitly, "tell me what you're planning before you make changes".
Both have issues. Claude is terrible at any language it hasn't been trained on, so anything not-mainstream.
If it doesn't know, it guesses. Which is why SLEIGH bombed, even with a compiler. It copied bits of code and guessed the ISA.

2026-02-18 01:09:54 UTC

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For clarity this was all a "okay challenge my preconceived notions" experiment with a fixed budget of £100, supplemented by Anthropic running an offer which gave me another £35.
I didn't want to just "hate AI", I wanted to know what it was good for and what it wasn't good for. That project goal is met.
Any problem which involves copy-pasting and reformatting, it'll probably do OK or well. My production music archive is now catalogued to track level and tagged.
(2/n)

2026-02-18 00:59:57 UTC

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I'm expecting 2008 2.0, "too big to fail, but really big this time".
I hope it leads to stronger market protection laws and regulators with sharp pointy teeth.

2026-02-18 00:58:54 UTC

Well, I just learned a hard lesson with £30 of Large Lie Machine usage costs.
Don't ever ask it to write Ghidra processor module (SLEIGH code). Claude completely hallucinated the instruction set of the processor even though I gave it an instruction set table.
Maybe describe the architecture and ask it for a template you can fill out. And then keep that template for future ones.
If you'll excuse me I'm off to write a COP8 SLEIGH description.
(also who the heck uses COP8 MCUs)

2026-02-18 00:42:17 UTC

Well that's going to screw a lot of companies' rolling upgrade plans, and a lot of home users' PC purchase plans.
Geeeez.
https://www.heise.de/en/news/WD-and-Seagate-confirm-Hard-drives-for-2026-sold-out-11178917.html

2026-02-16 20:11:52 UTC

I wish there was a good way to fix broken wall mounts on Cisco 79xx VoIP phones.
https://digipres.club/system/media_attachments/files/116/082/126/350/702/151/original/04bc18ea23bb5e5e.jpg

2026-02-14 22:59:55 UTC

Who knew bananas sounded so good?
https://www.tomshardware.com/speakers/in-a-blind-test-audiophiles-couldnt-tell-the-difference-between-audio-signals-sent-through-copper-wire-a-banana-or-wet-mud-the-mud-should-sound-perfectly-awful-but-it-doesnt-notes-the-experiment-creator

2026-02-10 11:19:11 UTC

Is anyone familiar with the English motorsports scene? How would a member of the public find out about events open to public spectators and photography?
A friend mentioned the MCC Edinburgh Run earlier and it's appealing; I narrowly missed seeing the RAC Rally a few years ago... I'd like to find more events like that, but not exclusively that.
#photography #motorsport

2026-02-09 02:23:28 UTC

I'm impressed. After cleaning the dust out of this SyQuest EZFlyer 230, most of the disks work.
The disc detect mechanism is a particular failure point - it gets filled with dirt, which holds the switch in the "disc ejected" position. Fuuuun.

2026-01-23 01:32:58 UTC

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Thanks to @npub12tr…tlud for the improved search suggestions.
https://digipres.club/system/media_attachments/files/115/941/832/147/877/738/original/471add4400e0f236.png
https://digipres.club/system/media_attachments/files/115/941/833/149/390/025/original/1db78518aebb3be4.png

2026-01-23 01:19:25 UTC

Harford County RNAV was clearly designed by a Lion King fan. Fox approved.
Yes it's real:
https://skyvector.com/files/tpp/2601/pdf/09277R19.PDF
https://skyvector.com/airport/0W3/Harford-County-Airport (RWY 19 IAP chart)
(thanks @npub1jyq…h5js for the tip)
https://digipres.club/system/media_attachments/files/115/941/771/426/025/912/original/8c406f4077323ab7.png

2026-01-23 00:58:12 UTC

I've been building a text-terminal interface for Koha:
https://github.com/philpem/koha-opac-tui
It's based on screenshots and photos I found of the Dynix user interface, with some elements of BLCMP I remember, and a couple of features (like MARC view) I wanted.
Please try it, thrash it, and report any bugs you find!
(ObFD: it was created with AI; I'm planning some rework because the code is quite meh in places)
https://digipres.club/system/media_attachments/files/115/938/093/845/832/364/original/08e4889159d47761.png
https://digipres.club/system/media_attachments/files/115/938/095/241/079/975/original/cac8d1773025dc40.png
https://digipres.club/system/media_attachments/files/115/938/096/406/131/205/original/2fc79a7d5bc58699.png
https://digipres.club/system/media_attachments/files/115/941/693/190/317/081/original/4cf6406cdc1964a3.png

2026-01-21 00:10:50 UTC

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Hybrid hits you real fast

2026-01-19 03:13:43 UTC

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Indeed. I've used it for a few things and it's helped a little, but I always review the work. And it's about as reliable as a cocky first-year student. It gets some things right, but it needs its mistakes pointing out.

2026-01-19 01:21:18 UTC

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That's not the Dynix ILS, it's Sequent's DYNIX operating system. Some fool's uploaded it and vibe-coded the description.

2026-01-18 18:13:14 UTC

I've successfully Dockerised the Koha ILS and set it up on my NAS. Now I want a telnet interface for it. Something like Dynix or BLCMP would be nice.
It's shockingly hard to find screenshots of these systems.
https://digipres.club/system/media_attachments/files/115/917/425/751/981/133/original/37a8dfe320dc208a.png
https://digipres.club/system/media_attachments/files/115/917/428/137/417/660/original/d60b0d987d368f31.png
https://digipres.club/system/media_attachments/files/115/917/429/049/257/455/original/af0417542cd040a0.png

2026-01-16 11:44:56 UTC

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I had to look that up. Egad, core rope programming. Apollo vibes.

2026-01-16 11:38:54 UTC

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But of course she couldn't tell you that...

2026-01-03 13:47:37 UTC

Hot take, most geek/nerd spaces are absolutely fucking toxic.

2026-01-01 20:27:17 UTC

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That would be Thunderbird.

2026-01-01 18:58:29 UTC

Tmw you realise you've been using Firefox so long, you still remember when it was called Firebird.

2026-01-01 15:01:25 UTC

I've uploaded some of my TS-7300 notes to Github. If you enjoy porting newer Linux kernels to weird ARM single-board computers, you'll love this...
https://github.com/philpem/ts7300
(my next task is getting the kernel driver for SD Cards updated and getting the FPGA Manager to load the Cyclone II gateware)

2025-12-27 21:44:26 UTC

One for fellow #ARM #Thumb and #gnu #binutils users...
Say I want to load the value "0x22000000" into R3.
Using "LDR R3, =0x22000000" drops the 32bit value in the literal pool, which encodes to 6 bytes.
A better encoding is: "MOVS R3, #0x88, LSLS R3, R3, #22" which saves 2 bytes.
Is there a pseudo-op or macro to generate the best possible encoding with GNU AS?
(I've been spoiled by RISC OS assemblers which kinda can, but now I'm writing code which others need to be able to assemble...)

2025-12-26 23:02:37 UTC

Ah, of course XKCD has a suggested design for the Deathdapter. https://xkcd.com/3186

2025-12-25 23:06:23 UTC

Christmas challenge: watch Babylon 5 without getting "MEESTER GARIBALDEEEE" stuck in your head

2025-12-21 00:50:29 UTC

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For certain business reasons, it'll never be paid off...
https://digipres.club/system/media_attachments/files/115/754/809/830/945/799/original/9f01e6bffb25fb86.png

2025-12-15 15:33:49 UTC

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The first one is the one I fell in love with. Alas I don't think I have room for the second one, unless I split it in two.

2025-12-15 12:02:41 UTC

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Curse you, I've fallen in love with their rolling pegboard workstation... I shouldn't be spending £700 this close to Christmas even if it would solve a lot of garage storage problems.

2025-12-15 11:28:20 UTC

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If anyone knows of any drawer units which would be about the right size to go under a workshop bench and don't cost a king's ransom, please let me know.
I'm leaning towards getting a couple of workshop tool trolleys, removing the fittings, and screwing them to the workbench.

2025-12-15 11:27:39 UTC

Workshop drawer units are such a pain to find. If they're not brand new and stunningly expensive, they're used, rusty, stupidly expensive and "sold as an upcycling project".

2025-12-11 18:26:09 UTC

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I hate to say it out loud, but some people will always use it as a purity test. I used to be involved in left wing politics and the furry scene and it was endemic in those spaces.
The polarisation of society and politics has not helped.

2025-12-11 09:35:59 UTC

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I often think the management would be better off running a heritage railway somewhere out of harm's way.

2025-12-10 15:46:33 UTC

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I think the biggest issue with Northern is their corporate culture, frankly. They've been bad under every single owner, including the operator of last resort.
They're still the only TOC who makes me feel like a criminal for buying a ticket, and who make me argue the toss for four weeks to get a Delay Repay claim sorted.

2025-12-03 17:23:29 UTC

Any Windows for Workgroups 3.11 experts in the audience?
If my network cable is unplugged I get "EMM386 has detected error #06 in an application at memory address 00B8:1460" and Windows won't start. Ethernet card is a Realtek NE2000-type PnP ISA card.
Anyone know of a fix? Other than keeping a second system.ini with networking turned off?
#retrocomputing #msdos #Windows311 #Windows31

2025-12-02 14:20:52 UTC

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It's weird to acknowledge that the retro computing scene with all its drama... Let's face it, it's mostly just people ripping each other off. It sucks but it's "I'll earn that back in a month or two" damage.
Meanwhile other scenes have "drama" with life changing consequences for the people involved.
I guess we're kinda lucky.

2025-12-02 14:18:11 UTC

I'm kinda getting used to the stuff I enjoyed dying out.
"Second biggest convention in the world allegedly allows animal abuse, blocks ignores and bans people who complain about it" is just another Tuesday really.

2025-11-25 17:18:24 UTC

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New blades are here. They don't cut much better but they do last longer.
Problem is the main root holding the stump in, seems to be under the tree. And now it's too dark to do anything about it. Sunrise is nearly 8am which isn't...great when I'm working.
Oh well, curry night for now.

2025-11-25 13:48:13 UTC

Lunchtime half-time score:
Leylandii stump 1, reciprocating saw blade 0.

2025-11-21 21:33:59 UTC

#Edinburgh is so scientific, they have fractional platform numbers. At least it's easier to remember than "Platform 0.36787968862663154".
https://digipres.club/system/media_attachments/files/115/589/825/482/647/793/original/5fdd7297d5cd8600.jpg

2025-11-19 18:56:31 UTC

Anyone have any recommendations for a relatively decent but cheap Pentium or MMX era laptop which doesn't suffer from crumbly plastics, good build quality, physical serial port and good MSDOS compatibility?
I need one for radio programming and my Libretto has Crumbly ABS Disease.
#retrocomputing #msdos

2025-11-19 18:54:27 UTC

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Guess who bought an MSATA-to-IDE adapter but bought an M.2 SATA SSD?
Yeah, this guy.

2025-11-19 18:38:44 UTC

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I'm going to find out that the other one works, aren't I.

2025-11-19 18:28:24 UTC

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It's life, Jim. But not as we know it.
https://digipres.club/system/media_attachments/files/115/577/775/820/941/966/original/e497fb9f8c974b63.jpg

2025-11-19 18:26:33 UTC

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Fun fact about the Libretto 110CT. If there's no hard drive installed, they'll play possum.
LCD stays off, but the machine responds to the escape key by (eventually) beeping - so it seems like an LCD failure.
I forgot this fact.

2025-11-19 18:22:46 UTC

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It's held in by the keyboard retention bar
https://digipres.club/system/media_attachments/files/115/577/752/958/776/156/original/42a5b880241b09fe.jpg

2025-11-19 18:21:54 UTC

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No screw here...
https://digipres.club/system/media_attachments/files/115/577/750/257/706/525/original/af0a2dd20baf4910.jpg

2025-11-19 18:21:34 UTC

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Keyboard cables and retaining straps - the two screws for these are the tiny button head ones. Then it's the RAM module.
https://digipres.club/system/media_attachments/files/115/577/743/026/647/792/original/ef5e78482445be5c.jpg
https://digipres.club/system/media_attachments/files/115/577/747/836/198/959/original/a9389e0f63d73bed.jpg

2025-11-19 18:16:43 UTC

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Shield plate next
https://digipres.club/system/media_attachments/files/115/577/729/965/709/062/original/bb369224b27b355d.jpg

2025-11-19 18:14:00 UTC

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CMOS Battery wiring, backlight connector wiring.
https://digipres.club/system/media_attachments/files/115/577/718/582/208/136/original/9d5bf9bb239e67a5.jpg

2025-11-19 18:09:51 UTC

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This is the only flat headed screw in the midframe and also larger than all the other screws. Except the one on the RAM slot.
https://digipres.club/system/media_attachments/files/115/577/699/711/094/893/original/8bbcfcd77345ec90.jpg

2025-11-19 18:06:59 UTC

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Anyway this is where the CMOS battery lives
https://digipres.club/system/media_attachments/files/115/577/691/370/720/750/original/253acb009c82aad0.jpg

2025-11-19 17:06:30 UTC

I hope one day someone 3D models a recreation of the #toshiba #libretto 110CT case plastics that I can get 3D printed. They just...crumble. :(
#retrocomputing
https://digipres.club/system/media_attachments/files/115/577/450/227/617/057/original/8afdc2e4cd3a9051.jpg

2025-11-14 01:44:03 UTC

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Was it food related?

2025-11-12 15:30:07 UTC

If you're the person who spunked £500 down and properly outbid me on the CSI / CSA Transputer Education Kit on Ebay UK a few weeks ago, I have just one question...
... can I please have a copy of the software disks, and some photos of the ISA card?
If you can't do mastodon, my email address is on https://www.philpem.me.uk/contact .
Boosts appreciated, feel free to share this post with non-Fedi friends!
#digipres #transputer #inmos #electronics #retrocomputing

2025-11-07 09:03:21 UTC

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Life is like a box of chocolates...

2025-10-28 18:53:38 UTC

"I think it's fair to say that anybody that lands on an aircraft carrier is mentally unstable"
- David "Bunny" Gunson, sampled in "loony2"
https://modarchive.org/index.php?request=view_by_moduleid&query=170709

2025-10-25 19:49:07 UTC

What kind of person emails someone to say "I can put your static site in an IFRAME", declare it a security vulnerability, and when told "it's a personal website..." demand a bug bounty and a mention on the front page?
I can't get my head around it.
#infosec

2025-10-25 10:54:34 UTC

It's now safe to turn off your oscilloscope.
https://digipres.club/system/media_attachments/files/115/434/431/909/697/122/original/34165eed90bdfd59.jpg

2025-10-23 17:44:50 UTC

This isn't a repair one should consider doing lightly. But sometimes there's no alternative. #retrocomputing #electronics #acornarchimedes #AcornComputers
https://digipres.club/system/media_attachments/files/115/424/712/463/210/474/original/1587a3c1fa917eaf.jpg

2025-10-22 23:26:06 UTC

docker compose scream-internally

2025-10-22 22:40:16 UTC

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There's a part of me saying "you should learn k8s" but the rest of me is going "one machine does not a cloud make".

2025-10-22 22:39:49 UTC

The amount of stuff I do with Docker Compose, you'd think I'd have a "glutton for punishment" merit badge by now.

2025-10-15 23:51:51 UTC

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down for you too?

2025-10-13 21:55:04 UTC

Nicking a meme from Bluesky:
In honor of spooky month, share a 4 word horror story that only someone in your profession would understand
Here's mine:
Unauthenticated remote code execution.

2025-10-13 15:01:38 UTC

Is this the future #OnlineSafetyAct supporters want?
https://digipres.club/system/media_attachments/files/115/367/454/390/717/660/original/148d26c453303f9b.png

2025-10-11 14:34:10 UTC

"This might be someone having a poke at the County Council"
https://www.bbc.co.uk/news/articles/crl5y255z6lo

2025-10-07 23:30:04 UTC

<philpem> isn't amd64 a third-party 64-bit patch on a 32-bit extension to a 16-bit enhancement of an 8-bit processor, originally derived from a 4-bit calculator chip by a 2-bit company who can't stand 1-bit of competition?

2025-10-07 16:31:22 UTC

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"probably"
Steam runs a lot of stuff through its WINE fork these days, and it works REALLY well.

2025-09-30 19:04:35 UTC

I love-hate NAND flash. In approximately equal measure.
Love: storage density
Hate: poor data remanence, bitflips
If it wasn't for Reed and Solomon or Bose, Chaudhuri and Hocquenghem -- it'd be a useless technology.

2025-09-29 18:38:26 UTC

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You can do worse, of course.
Normally you'd encrypt it as obfuscation (this is optional) then sign the firmware -- and verify the signature. This is fairly secure, and you only distribute the public key.
One implementation I saw distributed both keys and encrypted the firmware package with GPG.
If you haven't spotted the issue: the usual workflow with GPG is you give out your public key so people can send you encrypted e-mails.
You can calculate the public key from the private key.