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Sinclair ZX Spectrum Power Supplies – Safety Warning

The above Product Recall warning is from Personal Computer News in March 1983. It is a recall of power supplies for the Sinclair ZX Spectrum – the rubber key 16k and 48k models, as shown in the photo below.

They may also have found their way to be used on a Spectrum Plus (hard key, black model), although the Spectrum Plus power supply comes in a different case that matches Rick Dickinson’s superb design of the Plus machine itself.

These will work on the 16k/48k rubber key and the hard key Plus machines, if they are still serviceable. These power supplies are not suitable for any other model of Spectrum. But they need to be checked for safety, as well as functionality and that they are delivering the right voltage levels and polarity.

There was a potentially very serious fault with the design.

Sadly, quality control could be an afterthought at Sinclair. But cheap prices and time constraints often meant quality suffered. This was the case with the rest of the Spectrum design, especially the notoriously unreliable power circuit on the Spectrum board itself. But let’s face it – this trade-off between price/quality/time is how so many people’s lives were transformed by the Sinclair ZX Spectrum.

So why the Recall? Some units were produced where the mains 240V could potentially become live on the outer metal positively charged part of the barrel connector – despite this supposedly being the low voltage DC connector. Details of the units with the fault are shown on the recall notice. This is why I have made the image large, so that you can read it – if you can’t read it, please get in touch.

The Spectrum power supply was unusual in that the DC barrel connector that brought power to the computer was designed to be centre negative, but outer positive. Most power supplies of the time have centre positively-charged and outer negatively-charged. Like many things, Sinclair did this differently.

So if a user slipped on the smooth barrel connector plastic when plugging it in, and the fault with the mains 240V has occurred, they could have been injured or killed if they slipped off the barrel connector onto the metal! Or it could kill or injure your Spectrum too.

I am showing this here as a service to Spectrum users because some of these power supplies could still be out there in the wild and still emerging from storage or other places. Some of them have a sticker on the bottom if they have been checked after the recall. Only unethical sellers would remove these stickers – they should be kept on to show they have been checked.

And I am also showing you this as a safety warning, especially as some online sellers seem unaware of these faults and others I have seen have actually hid faults with power supplies that are being sold on eBay. This puts Spectrum users at unnecessary risk.

Other power supplies could have suffered damage during and since the 1980s. So it is wise to have them checked over properly, before you use one on your valued Spectrum.

I have sold many of these power supplies for the Spectrum. But unlike some online sellers, I am certified trained as an electrical safety (PAT – Portable Appliance Test) tester. All power supplies are fully PAT tested and will not be sold by PopeyMon Games and Fun if they fail the test.

I log all test results, as required by law. And I don’t sell them with illegal plugs on them – again, unlike some other sellers. Some sellers have power supplies with live and neutral pins that are unshielded on the plugs. This is illegal. I have even received some with cracked plugs! This is the mains 240V, not low voltage, so is very serious.

I replace illegal, outdated or unsafe plugs with new ones and with the right rating of fuse. This is part of the quality service that I provide. You cannot trust other sellers who don’t do this – ask them!

And if you are looking to buy one or want one checked, please get in touch. I will happily sell you one – fully tested and working – for the Spectrum 16/48k/Plus, for the grey +2 or the black +2 or +3. I also have a lot of other Spectrum parts, working computers and games for sale. I will happily put together a custom bundle for you.

I will be writing more about the Spectrum power supplies in the near future. Watch this space!

2 thoughts on “Sinclair ZX Spectrum Power Supplies – Safety Warning

  1. […] see my other article on the Safety of these models. There are many of these power supplies still lying in people’s lofts, or at the bottom of […]

  2. […] Before use all power supplies need to be checked for safety, as well as functionality and that they are delivering the right voltage levels, current and polarity. So please note that they must be checked before use, and check the Safety article. […]

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