Search found 6 matches

by Whopper
Mon Jan 29, 2018 6:43 pm
Forum: SALES
Topic: ZXpand+ ... 3.. 2.. 1..
Replies: 66
Views: 35390

Re: ZXpand+ ... 3.. 2.. 1..

SirMorris,

I have been looking (almost) everywhere for either a ZXpand or ZXpand+. If you are making another nbatch, please reserve one for me.

Thanks,

Whopper
by Whopper
Mon Jan 29, 2018 6:28 pm
Forum: Hardware
Topic: Sorry, Stupid question time
Replies: 2
Views: 1805

Re: Sorry, Stupid question time

Thanks Mark.

Now I know what my next project is going to be. :D

Whopper
by Whopper
Mon Jan 29, 2018 6:23 pm
Forum: Sinclair Misc
Topic: Photos
Replies: 2
Views: 2585

Photos

I have been asked for photos of my ZX81s. Heres the currently open one. received it today. :D
by Whopper
Mon Jan 29, 2018 5:26 pm
Forum: Hardware
Topic: ZX81s with the ROM fix
Replies: 2
Views: 1861

ZX81s with the ROM fix

So, I've just received another ZX81 fro eBay. Opened it up and it's another one with the ROM fix chips on top.

I only have three ZX81s, two being with the ROM fix, so exactly HOW rare are these things?

Whopper
by Whopper
Mon Jan 22, 2018 10:38 pm
Forum: Hardware
Topic: Sorry, Stupid question time
Replies: 2
Views: 1805

Sorry, Stupid question time

Hi All, I've just been watching a youtube video https://www.youtube.com/watch?v=14eL_oWhhXo about using a 32KB * 8bit SRAM chip to get an internal 16KB of memory. Looking at the datasheets for the 58256 and 62256 together with the ZX81 schematic I wondered if it was possible to also raise PIN2 of th...
by Whopper
Mon Jan 22, 2018 8:54 pm
Forum: Hardware
Topic: 2KB memory in a 1KB ZX81
Replies: 2
Views: 2169

2KB memory in a 1KB ZX81

Hi All, I've tried searching but couldn't find any results. I have just opened up my ZX81 and fins that it has an NEC D4016D 24 pin memory chip. LK1 is connected NIT LK2. So A10 is held at +5v. Is this a usual state of affairs, or just another case of using whatever was in the stores at the time? Ca...