Hello from Nashville, Tennessee USA!
Posted: Thu Jul 08, 2021 2:50 am
Hi there! I live in the suburbs of Nashville, Tennessee USA. I recently acquired a "used, untested" ZX81 from eBay, along with a Sinclair 16K memory pack, replacing the originals I owned as a teenager in 1981. My original was my first computer - I saw one of the ads Sinclair had posted in US computer magazines, saved up my money for a few months and ordered one by mail. I had that original for about a year and used it to learn BASIC and dip my toe into the early days of home computing. I ended up selling that original machine to a friend to purchase my next machine (an Atari 400). That machine in turn led me into the world of Atari computers and I never looked back. Until recently, that is. Over the last year I was getting the urge to replace that original Zeddie from four decades ago, so a few weeks ago I did.
Fortunately, I am an experienced amateur electronics modder and tech, with plenty of tools and the skills to use them, so "untested" doesn't hold much fear for me. As it turns out, the machine had been opened by a prior owner, which ruined the original keyboard membrane connector. After confirming the computer would power on to the expected "K" cursor, I have since cleared out the shredded debris from the edge connectors on the PCB, then removed the original RF modulator board and built a composite mod circuit on perfboard using instructions found here in the forums. A replacement keyboard has arrived now from the UK just yesterday, and I have a vLA81 en route to me from New Zealand as I write.
Today, I received a new CMOS-based Z84 to replace the NEC original, along with some 32K SRAMs. The new CPU is already in the machine, and one of the SRAM's will be used first as a basic 16K internal upgrade, then as a 32K upgrade once the vLA81 arrives. I also have new 3.5mm phono connectors coming to replace the badly worn and damaged originals. I also plan to replace the original 7805 with a modern switching replacement but I don't yet have one ordered. I meant to do that last week when I ordered the new Z84 and SRAMs but forgot.
My younger daughter is an artist and she will hand-paint the original embossed lettering on the case of the ZX81 as well as the RAM pack, even though I don't intend to ever use that except as a memento. After I get the little machine put back together, I look forward to exploring some of the software I never saw as a kid, and reliving some of those early experiences of laboriously typing in BASIC programs and the joy when they actually worked.
Anyway, that is my story and thank you for reading.
Today, I received a new CMOS-based Z84 to replace the NEC original, along with some 32K SRAMs. The new CPU is already in the machine, and one of the SRAM's will be used first as a basic 16K internal upgrade, then as a 32K upgrade once the vLA81 arrives. I also have new 3.5mm phono connectors coming to replace the badly worn and damaged originals. I also plan to replace the original 7805 with a modern switching replacement but I don't yet have one ordered. I meant to do that last week when I ordered the new Z84 and SRAMs but forgot.
My younger daughter is an artist and she will hand-paint the original embossed lettering on the case of the ZX81 as well as the RAM pack, even though I don't intend to ever use that except as a memento. After I get the little machine put back together, I look forward to exploring some of the software I never saw as a kid, and reliving some of those early experiences of laboriously typing in BASIC programs and the joy when they actually worked.
Anyway, that is my story and thank you for reading.
