Hello from Cambridgeshire, UK

Introduce yourself to your fellow forum members - what was your journey into the Sinclair world?
Post Reply
User avatar
Flatulentia
Posts: 93
Joined: Sun May 14, 2023 3:58 pm
Location: Cambridgeshire, UK

Hello from Cambridgeshire, UK

Post by Flatulentia »

Hi,

My first foray in to home computing was borrowing a friend's heavily modified ZX80 in early 1981. It was in a large homemade wooden case with a custom full-size keyboard and integrated PSU. I was instantly hooked.

I think it must have been some time in late 1981 when I'd managed to save up enough pennies to send off for a ZX81 kit, largely thanks to a £20 discount coupon in a Sinclair-related computing magazine. Total cost was £29.99 + £2.95 P&P if memory serves. I was a 17 year old apprentice electronics engineer at the time and couldn't wait to get my teeth into it.

The sheer excitement of switching it on for the very first time and seeing that cursor looking back at me is hard to describe, especially as I knew what a huge privilege it was to own an outright paid-for home computer at my age back then. I felt a simultaneous mixture of great pride and humility and have called the man behind it 'Uncle Clive' to this day.

I couldn't afford to buy a 16K RAMPACK so ended up building one using parts I purchased for a sensible price through my employer. That was quite an adventure too.

Time moved on and the Sinclair ZX Spectrum 48K arrived and went on discount for £139(?) from WHSmith, so I begrudgingly sold the ZX81 to raise funds toward that and started slowly buying and building add-ons for it. It ended up in a custom-made steel case with a custom-designed power supply and full-size keyboard and an MGT D Plus floppy drive interface and 3.5" floppy drive mounted in the front along with a "Snapshot" button.

Time moved on again and I realised how much I missed the old ZX81, so I bought one in an eBay auction in 2000 and have had the same one ever since.

It's grown over the years with the addition of a couple of Wilf Ritger's mods, namely 32KB of battery-backed static RAM and his "Why Wait?" mod. It's also had a backporch generator with composite video output fitted in place of the original UHF modulator along with a combined power/charge status indicator LED and 50/60Hz video switch around the back. I have more plans for it yet, but there's no hurry. It looks as though it'll be here for a few years yet.

I have a beast of a home-built gaming PC with a million times more RAM and a couple of overclocked Raspberry Pi Model 4 B SBCs carrying out light desktop, file-serving and media centre duties, but the humble ZX81 still keeps drawing me back, sometimes with moist eyes as I remember the very first time my kit-built ZX81 welcomed teenage me so gently to the world of home computing and inspired hobbies that keep me smiling to this day.
ZX81 with ZiLOG Z84 CMOS Z80, 32KB battery-backed Toshiba 55257 SRAM with charge status LED, Wilf's "Why Wait?" mod and switch-mode 5V regulator. 50/60Hz mode switch, composite video output with Zigg's back porch mod and 1080p60 HDMI output.
User avatar
1024MAK
Posts: 5118
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: Hello from Cambridgeshire, UK

Post by 1024MAK »

Hello and welcome to our forum Flatulentia!

:D :D :D

I know that you will enjoy this forum :D

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
User avatar
Flatulentia
Posts: 93
Joined: Sun May 14, 2023 3:58 pm
Location: Cambridgeshire, UK

Re: Hello from Cambridgeshire, UK

Post by Flatulentia »

Thanks for the warm welcome Mark.

Is that a pair of bridge chips I see in your avatar? ;)
ZX81 with ZiLOG Z84 CMOS Z80, 32KB battery-backed Toshiba 55257 SRAM with charge status LED, Wilf's "Why Wait?" mod and switch-mode 5V regulator. 50/60Hz mode switch, composite video output with Zigg's back porch mod and 1080p60 HDMI output.
User avatar
mrtinb
Posts: 1911
Joined: Fri Nov 06, 2015 5:44 pm
Location: Denmark
Contact:

Re: Hello from Cambridgeshire, UK

Post by mrtinb »

Thank you for your great story.

Welcome here.
Martin
https://zx.rtin.be
ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
User avatar
Flatulentia
Posts: 93
Joined: Sun May 14, 2023 3:58 pm
Location: Cambridgeshire, UK

Re: Hello from Cambridgeshire, UK

Post by Flatulentia »

Thank you.
ZX81 with ZiLOG Z84 CMOS Z80, 32KB battery-backed Toshiba 55257 SRAM with charge status LED, Wilf's "Why Wait?" mod and switch-mode 5V regulator. 50/60Hz mode switch, composite video output with Zigg's back porch mod and 1080p60 HDMI output.
dr beep
Posts: 2077
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Hello from Cambridgeshire, UK

Post by dr beep »

1024MAK wrote: Mon May 15, 2023 8:52 am Hello and welcome to our forum Flatulentia!

:D :D :D

I know that you will enjoy this forum :D

Mark
Welcome,
With that name I want a review from you on
MAKE-A-SHIT
User avatar
Flatulentia
Posts: 93
Joined: Sun May 14, 2023 3:58 pm
Location: Cambridgeshire, UK

Re: Hello from Cambridgeshire, UK

Post by Flatulentia »

I may take you up on that some day.

Fair winds!
ZX81 with ZiLOG Z84 CMOS Z80, 32KB battery-backed Toshiba 55257 SRAM with charge status LED, Wilf's "Why Wait?" mod and switch-mode 5V regulator. 50/60Hz mode switch, composite video output with Zigg's back porch mod and 1080p60 HDMI output.
merman
Posts: 5
Joined: Fri May 05, 2023 1:54 pm

Re: Hello from Cambridgeshire, UK

Post by merman »

Welcome. Used to live in Cambridge myself.
User avatar
Flatulentia
Posts: 93
Joined: Sun May 14, 2023 3:58 pm
Location: Cambridgeshire, UK

Re: Hello from Cambridgeshire, UK

Post by Flatulentia »

Thank you. Me too. I'm not many miles away now.

Something I forgot to add above was that my older brother used to work for Uncle Clive as a homeworker building the tiny Sinclair Micromatic pocket radios. Someone else who'd taken a batch home to build told porkies about being able to solder and had Araldited the components in the boards. :lol:

https://www.petervis.com/Radios/sinclai ... radio.html
ZX81 with ZiLOG Z84 CMOS Z80, 32KB battery-backed Toshiba 55257 SRAM with charge status LED, Wilf's "Why Wait?" mod and switch-mode 5V regulator. 50/60Hz mode switch, composite video output with Zigg's back porch mod and 1080p60 HDMI output.
Post Reply