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Sinclair ZX Spectrum +

I didn't really have much involvement with the Spectrum when I was growing up, apart from when I'd visit a friend who had one. It was then a case of loading things from tape and "don't touch the keyboard - it'll crash!" as one friend put it. His was the basic Spectrum with the rubber keys so maybe this won't be the same!

I used to have three of these, but (believe it or not) threw two of them away some years ago due to space considerations. I now deeply regret the decision as it's almost like I've chucked away a piece of history. Stupid. I hope they found good homes. All three of these were given to me by a friend who had similar space issues, but were missing the power supply units (PSUs), cables and cassette recorder/micro drives.

And here we are now: I still have the one machine, but am completely unable to test it having no PSU. So! A trip to eBay is in order.
According to the back of the machine the PSU should be output 9V, but says nothing at all about Amps. After a little bit of googling I've discovered that I need a PSU with the following spec:

Input: 240V AC @ 50Hz
Output: 9V DC @ 1.4A
Polarity: Negative centre, diameter 2.5mm
Source: World of Spectrum

I'll purchase one as and when I can, but in the meantime here are some specs and some photos :

Processor Zilog Z80A (Z8400A max 4MHz) clocked at 3.5MHz (dated 16th week, 1984)
ROM 16KB
RAM 32KB + 16KB = 48K
8x TMS4532-20NL3 (64Kb x1), lower half used of each chip
8x 4116 2N (16Kb x1)
Video 256x192 graphics
32 colums x 24 rows text
16 colours through UHF module/TV
Audio 1 channel (2 channel using software) through onboard speaker, 10 octaves
Keyboard Membrane based, 58 keys, plastic keys
Ports Expansion edge connector
3.5mm audio Mic port
3.5mm audo Ear port
9V DC in

SpectrumPlus_TopView SpectrumPlus_Underside SpectrumPlus_Rear
SpectrumPlus_Logo1SpectrumPlus_Logo1
SpectrumPlus_Inside SpectrumPlus_ManufactureDate


Update 23rd August 2015

I've recently purchased a Tenma 72-10495 benchtop dual PSU and so have used that to test the Spectrum+. Surprisingly, it powered up OK first time, although before I tuned the TV all I could hear was a rapid ticking noise. Turned out to be a stuck down key stuck lol. After rectifying that, the machine worked fine.
The current draw is roughly 580-590mA (at 9v), although this with the computer not running anything but BASIC.
Here are a few pictures:

SpectrumPlus Initial Display SpectrumPlus Running a program SpectrumPlus Tenma power supply

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