Power cut! But don’t worry, we still have music. #EmergencyToastrack #StormAmy #SAA1099P

Photograph showing a computer, screen, battery pack and a mug illuminated by torchlight and the glow of the small screen, in the dark.

Oh you know, just brushing up on my British Standard logic symbols. (I’ve never seen these before).

&10;The good author's guide to explaining projects&10;IF YOU WISH to submit articles to sinclair Projects we would appreciate it if you adhere to the following rules.&10;Although they are not exclusive it would help us to evaluate projects if there is some element of compatibility between different pre-sentations.&10;&10;• All manuscripts should be typed with double-line spacing.&10;• Logic symbols should follow British Standards.&10;• Circuit symbols should follow&10;British Standards.&10;• Circuit diagrams should have the values of the components shown, not a reference to a component table.&10;• Parts of integrated circuits should be designated&10;in this way&10;1/4 74LS14, not ICSa for example.&10;• All circuits should be designed for construction using standard Vero-board. Any printed circuit board designs are likely to be returned for conversion. Submission of a project based on a PCB will not exclude future publication.&10;• Any constructional detail which is unusual or slightly complicated should be illustrated with simple hand-drawn diagrams, showing how it can be implemented.&10;&10;For those who are unfamiliar with British Standards logic symbols, they are shown here. The reason for using BS symbols is simple, although controversial; they are used extensively in the British educational system and in British industry. As most of our readership is in those areas we use circuit symbols which are most familiar.&10;&10;U.S.:&10;AND&10;NAND&10;OR&10;NOR&10;NOT&10;EXCLUSIVE OR&10;&10;BRITISH STANDARD:&10;AND&10;NAND&10;OR&10;NOR&10;NOT&10;EXCLUSIVE OR&10;&10;SINCLAIR PROJECTS June/ July 1983&10;June/July 1983&10;An independent magazine published by ECC Publications&10;SINCLAIR PROJECTS&10;&10;&10;THE MAGAZINE FOR THE SERIOUS SINCLAIR USER&10;&10;&10;SIX GREAT PROJECTS&10;CENTRAL HEATING PART II&10;GRAPH PLOTTER&10;DECODER PART II&10;SOUND GENERATOR&10;JOYSTICK FIRE BUTTON&10;SAVE AND LOAD&10;

Have you ever wanted to load arbitrary Microdrive files using machine code, but Sinclair’s hook codes let you down? Well: want no longer and behold: SHADOWLOAD!

#zxSpectrum #microdrive #interface1 #asm #z80

Photograph of a ZX Microdrive unit. Its single baleful red eye glimmers with menace; its tongue stuck out at you in defiance. Or it might just be an unilluminated red LED and a partially-inserted Microdrive cartridge, but who can say.

0x002A

Good morning! (It’s Snorkin’ Time!) ☕️🎩

Photograph, outdoors, garden. In the foreground a WhatHoSnorkers coffee mug with an Aeropress atop, such that it looks like Snorkers is wearing a top-hat. (Well sort of). The mug is on a little table and is next to a Cambridge Computer Z88 portable computer. The sun is rising in the background. It is evidently Snorking Time™️.

I just finished building my new PC! #RC2014 #RomWBW #Z80 #CP/M

Photograph of a little blue box with switches lights and small LCD screen.Computer with the lid removed. Inside are blue modular circuit boards and several wires connecting them here and there. Photograph of the assembly process. The main backplane is pictured with a few modules connected, and the front panel is propped up nearby being tested. Multimeter and soldering iron in the background.

Upgrade time! I’ve added a combined 512K ROM / 512K RAM card to my RC2014 which replaces the two respective cards from my old setup and also brings the RomWBW system to explore. I’ve had the upgrade kit since the Retro Computer Festival in November and finally built it tonight! #Z80 #CPM

RC2014 Pro modular computer. The combined RAM and ROM card has been separated from the backplane.RC2014 powered-up with green LEDs glowing brightly.

I love an 80s computing book with completely unhinged technology metaphors.

Photograph of the from cover of “The Hacker’s Handbook” a ZX Spectrum 48K communications guide by Longman publishing. The illustration depicts orbital ZX Spectrums encircling the globe.A diagram from the book. The concept of duplex send and receive communication lines is, for (presumably) some reason, illustrated as two pairs of handlebars with the brake lines connected such that pulling the right hand brake lever raises a flag on the left hand lever of the other side.Another illustration and more abject nonsense. A cartoon of a car driving on a winding road that passes over a bridge and ends up at a car park. Along the way a police officer is marshalling traffic. The road is suppose to represent the telephone; the cop is software; the road (“highway”) also represent the cable; the eight lanes (annotated but neither depicted nor explained) lead to the car park with eight spaces that represents the screen.Biblically-accurate rendering of RS232 from the perspective of the computer. Allegedly. I quite like this one to be honest, I might get it as my next tattoo. We’re back to handlebars but this time with six brakes and umpteen flags. The brake lines are labelled TxD, RxD, CTS, RTS, DTR, DSR, circuit common, and DCD.

What ho, Saturday‽

A photograph of my desk with a book, a notepad, a pencil, a mug of tea and a calculator.

Happy upgrade day, gang! (I retired my clunky old bodge-wired external IDE interface in favour of a sleek internal fancy one). #ZXSpectrum #Plus3e

A ZX Spectrum +3e main board in a clear Perspex sandwich (in lieu of its original case). Inside can be seen all the gubbins including a new IDE interface with a bright red LED.A picture showing the IDE interface in more detail. It has taken the place of the Z80 processor. The adaptor sits in the old DIP socket and extends to the right, where the floppy drive would normally be mounted, but in this system has been removed. A CF card is attached. Instead of the original DIP Z80, this board has a surface mounted QFP variant (which is much smaller). Not quite in shot is one of the two EPROMs which have replaced the original mask ROMs.

Fitting ZX-HD with a new Raspberry Pi Zero. It’s a socket connection which means that normally there’s no need for soldering, but this Pi Zero had no header pins so they needed to be fitted first.

Partially reassembled ZX-HD interface with back removed showing a Raspberry Pi Zero inside. Also pictured: soldering iron and various soldering gubbins.

Are any ae yous intae Spreadsheets? They’re sick, man. #productivity #hustle #workSmarterNotHarder

Photograph of the clamshell case, manual and 3" disk for Tasman Software’s “TASCALC” which is a spreadsheet application for ZX Spectrum. The styling is familiar among the Tasword family of software. The disk label for TASCALC is metallic gold/bronze colour.

Mmmm-rrrrrr Crrrrrrrzmrrrrrrzz, rrrrvrrrrr-rrrrrnn!

ZX Spectrum loading screen featuring a festive zombie

I’m about a week late but I’ve found something “healthier” and all together more fun than chocolates. #advent #zxspectrum

A wall-hanging advent calendar composed of several numbered canvas pockets that happen to be about the size of a standard boxed cassette tape. I’ve refilled the pockets with a selection of ZX Spectrum games including Moley Christmas, Mrs Mopp, Seymour goes to Hollywood, Codename Mat and Shinobi.

Gotta toast fast #zxspectrum

Disassembled ZX Spectrum+ 128. The iconic finned radiator heatsink has been detached, as has the voltage regulator. Also pictured is a syringe of thermal compound normally used on PC CPUs or GPUs or whatever.

Day #2 in Cambridge In the city centre on the Sinclair and Acorn trail.

The Corpus Clock. An enormous gold chronograph. It’s eh, quite striking. Horologically speaking.The former offices of Uncle Sir Clive at 6 Kings ParadeThe gleaming and modern official Rasperry Pi shop. I don’t really need another Raspberry Pi so I just came away with a branded mug and tote as a keepsake.The highly-recommended Jack’s Gelato was great and understandably busy.

Retro Computer Festival 2024 Centre for Computing History in Cambridge I had a lovely time and spoke with many lovely people! A very welcoming bunch of retro folks, with so many interesting stories to share. Thanks to the CCH for a great event!

Main exhibition space at the Centre for Computing History. The room is filled with tables laden with vintage computing equipment.ZX Spectrum prototype mainboard and keyboard on display at the museum. Several computing devices showing key-based entry systems from simple keypads and membrane keyboards to full travel keys.A display of Heathkit computers magazines and catalogs from the late 70s. The machines are operating, with their numerical displays glowing.

Fun with MIDI!

Short clip showing a RaspberryPi with a MIDI hat connected. The blueish white RX indicator is blinking furiously. (It’s playing GRABBAG.MID but you can’t hear it because this is a GIF).

The Micro Enquirer (Spectrum)

The Micro Enquirer (Spectrum)&10;by Christopher Bidmead and Benjamin Woolley for Computer Answers, on a ZX Spectrum +3 with an external floppy drive cable attached, and a Kempston mouse interface nearby.

I am on my holidays.

Animated GIF. Image shows a wall mounted hotel room TV displaying the loading screen of Future Knight on ZX Spectrum (the computer is on the desk loading the game from cassette tape).

I’m working on my (second ever!) ROM hack this weekend and a random glitch has given me an idea…

A screenshot from Jetpac on the ZX Spectrum. The rocket ship graphics have corrupted and it has turned into an improbable tower of jumbled spaceship parts.Matchbox “Con-nect-ables” branded toy vehicles in a retail hang-card blister pack. The toys are segmented so you can recombine them in interesting ways such as adding wings to a car, and so on.

Work in progress! (This photo didn’t attach to the previous post for some reason). I’d had the thing open years ago to service the belt or something but the old brittle wires gave way and it took some effort to deduce what goes where! It languished in the garage for ages; being raided for parts a couple of times, but I decided to give it another go last night. I couldn’t find a schematic for the whole unit, but the data sheet for the LA4160 amplifier IC was very helpful.

Photograph of a disassembled shoebox style cassette recorder. There is a cassette in the exposed mechanism and many wires all over the place. I’ve connected a logic probe for some reason. It’s playing Matchbox Twenty but you can’t hear it because this is a photograph.

Fixed it! I had to improvise an output socket—I harvested the original one when I thought this player was beyond repair, but this was my childhood Spectrum cassette recorder so I made the effort to fix it. #HiFi #ZXSpectrum

Cassette recorder with an improvised earphone socket made from a small breadboard and some jumper wires. There’s a resistor for decoration but it’s not serving any electronic purpose. The breadboard has been optimistically labelled “HI-FI”.Overhead photo of the cassette recorder showing lots of patina from decades of wear and tear. It’s dusty, scratched and worn with a small faceplate around the tape counter missing. A red cassette tape can be seen through the deck window. The label reads: SKATE OR DIE; DOUBLE DECKER TAPES.A modified ZX Spectrum with a white key mat and a shiny RTS sticker (see RoseTintedSpectrum on YouTube dot com).

Midnight maths club

Tonight we’re learning (or really just enjoying looking-at) bifurcation diagrams generated by Feigenbaum constants (…and very slowly plotted on a ZX Spectrum!)

Photograph of a CRT telly displaying a Feigenbaum constant bifurcation diagram generated by a ZX SpectrumPhotograph of a CRT telly showing a BASIC listing of the program that generated the diagram in the other picture. The program is by Ettrick Thomson.

I had a great time at the Acorn Computers User Group meet-up last night in Falkirk. I was notionally representing SAM Coupé, but I spent almost the entire time learning about Elks, Masters, and RISC OS machines (and much more!) More pics at Spectrum Computing forum.

📷 Tosk / Retro Rendezvous

SAM Coupé computer with a few expansion cards plugged in, connected to an LCD television. On the screen is a blue and green horizon. Disks (and a spare SAM Drive) are scattered around.