Panda RAM pack - adequate images?

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msknight
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Panda RAM pack - adequate images?

Post by msknight »

I know the Panda RAM pack is in the hardware database somewhere, but does it have adequate images of the internals? (I tried to find it, but couldn't.)

Basically, before I knew about the hardware database, I had encountered the Panda 16k RAM pack, thought it was a mess that wasn't worth trying to rescue and binned it, before taking proper pictures of it. Basically, it looked to be a load of 1k chips banded together in two boards that were really dodgily put together.

However, I had shot a youtube video and have some stills from that, if they are worth anything to the database.

EDIT - I added them here.

Michelle.
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1024MAK
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Re: Panda RAM pack - adequate images?

Post by 1024MAK »

The Panda RAM pack uses eight 4116 16K bit DRAM chips, giving your ZX81 16K bytes of RAM.

Mark
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msknight
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Re: Panda RAM pack - adequate images?

Post by msknight »

This one doesn't. It's in landfill. Very poor construction... but of the time I guess.
Moggy
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Re: Panda RAM pack - adequate images?

Post by Moggy »

1024MAK wrote: Wed Feb 07, 2024 10:43 am The Panda RAM pack uses eight 4116 16K bit DRAM chips, giving your ZX81 16K bytes of RAM.

Mark
That's strange as Iv'e had three of these at various times and all of them including the one I still posses have 8241 chips fitted not 4116.
Obviously they must behave in the same way .

Of all the RAM packs I've owned I found these to be the most reliable and not as electrically fragile as the Sinclair or Memotech versions , it also has a slot for expansion to 32k.

Lardo posted some better pictures a few years ago and his pack used the chips as mine.

https://www.sinclairzxworld.com/viewtop ... ack#p43130
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1024MAK
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Re: Panda RAM pack - adequate images?

Post by 1024MAK »

Moggy wrote: Wed Feb 07, 2024 2:08 pm That's strange as Iv'e had three of these at various times and all of them including the one I still posses have 8241 chips fitted not 4116.
Ahh, you actually mean the National Semiconductor MM5290 (that's the type number). They are direct equivalents to the 4116.

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Re: Panda RAM pack - adequate images?

Post by Moggy »

MM5290 not 8241!!

No wonder I couldn't find a bloody data sheet for them! :lol:


Thanks for that Mark, much appreciated. :D
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