The ZX Spectrum - Where it all started

It really all started in maths class when Mr Lane sat me down in front of a teletype (which I just assumed was a computer).  How was I to know that it was connected to the local college with an acoustic coupler modem?

  The simple arithmetic program he ran immediately died when I typed an O (Oh) instead of 0 (zero).  I asked him how to fix it and a lunchtime or two later the program was more robust.  Life changing.  Really.

Soon after a Research Machines 380Z showed up!  It had a VDU and could display block graphics.  Pure green-glowing magic.  I typed in simple BASIC programs on the teletype and the 380Z whenever I was allowed.

During the summer-holiday my mate Vince (no, not that one) lent me his prized ZX81 while he was abroad.  A home computer!  Truly Glorious.

When the ZX Spectrum was announced I pestered my parents.  Shortly afterwards an order was place for a 48K model ("for the family").  The wait for it to arrive almost killed me.  But arrive it did - a grey-key revision 1 (it turns out).  I bought books.  I bought magazines.  I typed in programs.  I was learning fast.  But something was wrong.  Larger programs didn't work.  A call to customer support got us a way to figure out the RAM size.  It was only 16K**.  Devastated!  So my Speccy went back to Uncle Clive.  Another soul-crushing wait.  The unit that came back (presumably the same one) had the full 48K.  Excellent!  On with it!  I started to tinker with Z80 machine code (or 'assembly' if you wish) and I was really hitting my stride.  Awesome!  Awesome, that is, until the day I plugged in the Speccy and it was dead.  Uncle Clive got his dead Speccy back, and we got our money back.  Along came a Commodore 64 (that day - from Comet or similar).

And that was that.  Until spring of 2025 when I bought an untested 48K Spectrum on ebay.co.uk and arranged to get it to Canada...

** These days of course, I'd just pop it open.  I wonder if the 32K daughter-board was just loose (which I assume was a thing).

I was fully aware that my new-old Speccy might not be 100% when it arrived.  I had the foresight to order a new keyboard membrane but I knew it might be most beneficial to have a way to run diagnostics...

The gold-standard for Speccy diagnostics solutions is the "Steamcard Pro" - but I wasn't able to get one in a timely manner.  So I created my "Speccy ROM+Diag" card.  It's absolutely nothing special - but it has everything the time-crunched and budget conscious Spectrum tinkerer needs to check voltages, run diagnostics and probe expansion-port signals.  Oh yes - it plays games too.  More details on the Speecy ROM+Diag can be found here: Speccy ROM+Diag.

The short version of the story is that with the use of my diag card (and, more importantly, the Alford/Smith and Retroleum diagnostics) I found that the ULA in my speccy was marginal (it was only capable of displaying half the border-colours.  Weird).  I sourced a vLA82 and my Speccy is perfect once again.  Oh, and the new membrane came in very useful too.

Onwards!