ZX81 with strange addon board soldered to it

Discussions about Sinclair ZX80 and ZX81 Hardware
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1024MAK
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Re: ZX81 with strange addon board soldered to it

Post by 1024MAK »

The Sinclair power supply unit does not need an earth/ground connection. If the existing mains plug is not suitable for your sockets/outlets, then obviously you will either need a suitable adapter or arrange for the plug to be replaced with a more suitable type. I don’t know the requirements in your country.

It’s not essential to test the voltages with a multimeter if you don’t have a multimeter. That is, you don’t have to.

The “RF” cable that was originally supplied has a phono/RCA/cinch connector for the modulator end and a suitable connector for the aerial socket on the TV in the country where the machine was sold.

In the U.K. the aerial sockets and plugs are Belling-Lee connectors type 9,52.

These cables were once common from computer shops, but are now hard to find. So you may have to make your own or find someone to make one up.

Mark
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mstreurman
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Re: ZX81 with strange addon board soldered to it

Post by mstreurman »

The original power supply is sadly enough not working at all... So I bought a cheap universal power adapter that could run 9v 1A and it seems to work. So this addon is indeed a sound-mod that beeps every time you press a button and it is quite high pitched, so I'm kinda on the fence if I am going to remove it or not, especially as this will be used to play some games, it could be more distracting than anything else. maybe I will add something that brings down the pitch a bit so it only makes sort of a tapping sound... don't know yet... So the next step is creating a RF cable that will give me an output to the screen... That shouldn't be too hard I think, that is.. IF the modulator is still working.
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