A high street magazine cover promising to explain SIN, COS and TAN is glorious, though. ❤️

Ian Stewart is a lecturer in mathematics at Warwick University, the author of twenty books, including Concepts of Modern Mathematics, Get Knotted! and - jointly with Robin Jones - PEEK,POKE, BYTE and RAM - BASIC Programming for the ZX81.

Especially when it is by Ian Stewart a university mathematics lecturer.
The article by Andrew Hewson on floating point is to the same high standard. The work of both authors is still being printed today.

It was more varied than that. On the ZX80 they ran out of token space so one used RANDOMISE and then the letters U S R which was never tokenised. They ran out of ROM space on the ZX81 so the token was just RAND. On the ZX Spectrum plenty of space so they used the international spelling RANDOMIZE.

ZX Spectrum power supply.

Thanks Juan. Mine passed its test in February 1983.

Sinclair 1983 ZX power supply. “MADE IN UK”. Those were the days.

Just checked. All OK.
This has been re-checked by Sinclair Research.

Mine has a cotter pin that you have to file to match the slope of the other side.

Amstrad could not see what was wrong with this behaviour, which was not their fault and applied to all 128K BASIC implementations.

Wrong page. It is the next image, Page 146 that has the error.
As I pointed out to Amstrad at the time, NEW will alter three bytes in memory whether they are above RAMTOP or not.

The addition of the three lines produces 1 2 3 And after a PAUSE and CLS 4 5 6

Elsewhere in the PLUS 2 manual and all other ZX Spectrum manuals, it is stated that CLEAR does a RESTORE.

The 1984 Pocket Guide to the Sinclair Spectrum by Steven Vickers. He also wrote a Pocket Guide for ALL Forth users. (Not just Jupiter Ace users)

Steven’s correction of the CLEAR command in his 1982 Spectrum manual.

It is useful to add the following lines to the large program.
92 PAUSE 100
94 CLEAR
96 GOSUB 110

This shows that, as pointed out in the Pitman Pocket Guide to the ZX Spectrum, CLEAR does not perform a RESTORE.
There is another mistake that applies only to 128K manuals on that page.

“Does he take sugar?” -tea lady.

Popular Computing Weekly, Apr 1986

Comic. [Sign above four people. A person sits at a desk working on a laptop. A person with ponytail is talking to person with white hat. A person with short hair walks away.] SIGN: It has been [-0.00000000000000044] days since our last floating point error

Day Counter

xkcd.com/3228/

That is a wooden mock-up made by industrial designer Rick Dickinson :-)
I stared at that advert for 28 days until my rubber chum arrived.

So, moving backwards, this kind of incredibly tight display timing isn't new as such, although the current crop of implimentation is certainly special.
We've got a David Webb type in, Paul Farrows flicker free zx80 and Andy B's uridium available as a few contemporary examples. All building on ideas.

YouTuber lands on Moon using a ZX Spectrum. Conditions apply BASIC and bit-banging used to guide a simulated lander down to a virtual lunar touchdown Could Sinclair's 48k Sinclair ZX Spectrum land a spacecraft on the Moon? YouTuber Scott Manley decided to find out, and the answer is… kind of.…

YouTuber lands on Moon using a ZX Spectrum. Conditions apply

PicoZ80 is a Drop-in Replacement for Everyone’s Favorite Zilog CPU Hackaday Article

PicoZ80 is a Drop-in Replacement for Everyone’s Favorite Zilog CPU

Nice!

Price matched by Amazon but beaten slightly by Smyths Toys. A handy machine in UK.

Good to see a letter on Page 7 from Mike Lord who wrote many books and magazine articles for the ZX Spectrum, ZX81 and Acorn machines. A tip for clearing the key state with a short PAUSE before an interruptible pause.

An early Christmas present from Spectaculator www.spectaculator.com/2025/12/spec...

LOAD ZX 40: "Inside the ZX Spectrum" - Steve Vickers YouTube video by LOAD ZX Spectrum

Steve Vickers remembers the three or four hundred Forth enthusiasts who bought the machine :-)

youtu.be/kgWj5RRTDCg

The Jupiter ACE was built by two ex-Sinclair engineers who helped design the ZX Spectrum — the only home micro to run FORTH! The archive preserving its legacy needs support. Help keep this Sinclair heritage alive! 🕹️ https://www.jupiter-ace.co.uk/

I found this online. From 1973. Lovely code. I remain fascinated.

It is influenced by this 1973 ‘C’ program. It is still MAGIC.

The slight alterations to the original program (posted by Eric Schraf on Facebook) enable the ZX Spectrum to store the output in a simple string. No 255 character restrictions on any ZX machine. This can be printed to the screen and the variable is saved when the program is saved. The BASIC starts slowly using two nested loops but quickens as the loops work downwards. Original BASIC runs on any computer with enough RAM e.g. ZX81, CPC464, C64 etc. This is now my favourite BASIC program.

I ran the program on my PC with my favourite ZX Spectrum emulator Spectaculator turned up to 20 times normal Z80 speed in the drop down control menu. I initialized a new variable v$ at the start and wrote to it at line 236 onwards. At the end v$ held 1864 printable digits all perfect. MAGIC!

Thanks. I started with the ZX Spectrum but had to go backwards to see how it had evolved and then again to the ZX80 where I found routines carried forward to the Spectrum (and Interface 1). For the ZX80 I used the Logan/O’Hara labels to make the evolution visible.

My morning: read the post, then read the linked Wikipedia article (en.wikipedia.org/wiki/Sinclai...), then read the linked Incomplete Spectrum ROM Disassembly (web.archive.org/web/20150901... and finally read the linked Online Gosh Wonderful ROM Assembly File (web.archive.org/web/20150826...).

Sinclair 4K BASIC for the ZX80 In my study of Tiny BASICs, one I overlooked reviewing was Sinclair 4K BASIC, which stands out for its unique keyboard, its approach to graphics, and its memory usage.

Sinclair 4K BASIC for the ZX80 https://lobste.rs/s/tukeyq #historical #retrocomputing

A Few Moments Later… Rather slow but a fascinating PI Spigot Algorithm

That’s a fascinating complete BASIC program that outputs four digits at a time rather slowly.
I am thinking running it on an emulator at 20x speed and outputting to a ZX Spectrum string.

Happy Pi Day!

The most logical place for the printer buffer is after the system variables and it would need two bytes. With the present position the high byte could be hardcoded at $5B but that was not done. It invites use because it is labelled “Unused” but alteration can crash the ZX Spectrum. A fun diversion.

Far from being unused, system variable 23681 is the high byte of PRCC so this moves the printer buffer down the screen 🙂

Alternativaly, if you disconnect your Speccy printer -

10 FOR I = 64 TO 87
20 POKE 23681,I
30 LPRINT “* THANK GOODNESS IT’S SATURDAY *”
40 NEXT I
50 PAUSE 0

Quicksort inventor Tony Hoare reaches the base case at 92 Classicist, philosopher, wit, and one of the greatest British computer scientists of all time Obit  Professor Charles Anthony Richard Hoare has died at the age of 92. Known to many computer science students as C. A. R. Hoare, and to his friends as Tony, he was not only one of the greatest minds in the history of programming – he also came up with a number of the field's pithiest quotes.…

Quicksort inventor Tony Hoare reaches the base case at 92