CPCWiki forum

DK Tronics 464-64k-10/90

A short time ago I acquired this from N.Z.
I thought I might like to update it to 256K.
BUT it is later model SMD .
Here are the Photos do what you want with them.

Ray 10 November 2015

https://www.dropbox.com/s/m7ef40rz7n9h1ow/DK%20Tronics%20464%2064K%20Memory%2010%3A90%20.zip?dl=0



Ray

Ooh, this looks like it's never been used!

Obviously not as easy as the thru-pin version, but I'm sure there could be some solution to upgrade this to 256K with some chip swapping and maybe some piggy-backing?

Bryce.

1st time I see this version, I was not even aware about CMS version for this RAM extension. Nice piece of hardware.

Nice piece of hardware. I would rather leave it like it is (and save it!) and get an X-MEM instead of piggy-cracking / destroying an original for only small 256 KB of RAM (which is only small 188 KB free in an RAM disc anyway). Save it and be proud to have it. It may be the only one left.  :) :)

Quote from: Bryce on 14:34, 10 November 15
Obviously not as easy as the thru-pin version, but I'm sure there could be some solution to upgrade this to 256K with some chip swapping and maybe some piggy-backing?

Should be better to keep it intact... It is not so hard to exchange it for an older version.

They're not as rare as you think. I have come across them quite often and several other members here own one too. It's a nice design, but the standard 256K mod doesn't work for obvious reasons.

Bryce.

Okay, this might sound like a daft question but what's the difference between this model and other models? I'm not seeing a difference between the photo and my own 64k memory pack; which I'm pretty sure isn't rare or special.

The difference is only visible inside. The original is thru-pin technology (and can easily be upgraded to 256K if it's the 64K version), this version uses SMD components: http://www.cpcwiki.eu/imgs/8/8d/2_-_64Ks_-_04_.jpg (http://www.cpcwiki.eu/imgs/8/8d/2_-_64Ks_-_04_.jpg)

Bryce.

Quote from: Bryce on 21:33, 10 November 15
The difference is only visible inside.

Yeah, that would explain my confusion. I don't open things up unless it's really, really necessary. :)

Here is the picture gallery from the Wiki.

Both types represented there for a while now.

Dk'tronics Memory Expansion Gallery - CPCWiki (http://www.cpcwiki.eu/index.php/Dk'tronics_Memory_Expansion_Gallery)

Cheers,
Shane

Yeah, but unfortunately only low-res.

Bryce.

Nice one Ray. Scored the original box  :D

Damn , I'd even consider buying another one just for that. Lol

But like yours , mine is also the SMD model. Like others are saying , I'd leave it be and get an X-MEM if you really want more than 128k.


Robert

Can't imagine that there are much built in 1990.  :-*

The box states 464plus. So even later than that I guess.

Funny thing about the box is: It stated to be a 64 KB expansion, BUT also stated that it extends memory to 320 KB. Now...  :o

Thanks ALL


I posted the photos as i had not seen one before.
I then discovered it in the WIKI.
I won't be modifying it, it stays as it is.
The post was just for information.
Ray

Quote from: TFM on 23:26, 10 November 15
Funny thing about the box is: It stated to be a 64 KB expansion, BUT also stated that it extends memory to 320 KB. Now...  :o

Wow, you're right, well spotted. Maybe I need to take a closer look at one of these. The circuit hasn't been reversed yet and there no schematics available as far as I know.

Bryce.

However, the expansion will only provide 64 KB (what ever the box tells), because it contain two chips called:


8948 B USA
MT4067EJ-10


They are 64K x 4 DRAM PAGE MODE ICs.

Quote from: TFM on 23:26, 10 November 15
Funny thing about the box is: It stated to be a 64 KB expansion, BUT also stated that it extends memory to 320 KB. Now...  :o

64k+256k Silicon disk from DKTronics = 320k i guess...

Very misleading... but a way to enhance business.  :-\

What does the 10/90 mean?

Quote from: steve on 23:32, 18 November 15
What does the 10/90 mean?

Hi,


I guess it means the October 1990 revision.


There are at least TWO different versions of the Dk'tronics 64K extension. One made back in 1986/87, and one made in 1990.
The differences are probably the number of components and layout of the PCB.
I guess the 1990 version was much cheaper to make.


You could check out the following Dk'tronics page. Dk'tronics memory expansion - CPCWiki (http://www.cpcwiki.eu/index.php/Dk'tronics_memory_expansion)


I "think" I have both versions of it. If someone is interested, I could scan both PCBs and have them uploaded on the CPCWIKI.


Yours

Terje Grind
NORWAY

Hi! I assume you got everything CPC, so let me ask you this question: Do you have the HD64180 expansion card for the CPC? It's very rare. I would exchange it to the original CPC464 with Vortex Expansion and Vortex Winchester the Company used, the HD still contains the customer database. I got that when they left CPC market.

Quote from: TFM on 17:05, 19 November 15
Hi! I assume you got everything CPC, so let me ask you this question: Do you have the HD64180 expansion card for the CPC? It's very rare. I would exchange it to the original CPC464 with Vortex Expansion and Vortex Winchester the Company used, the HD still contains the customer database. I got that when they left CPC market.

Hi,


No, I don't have the HD64180. Actually I don't think I haven't hear about it at all  :-\ 

Does it have something to do with the "sidewagon" that was released for the CPC in Germany. It was mentioned in the Danish Amstrad Bladet in one of the issues.
For those who doesn't know what I'm talking about, it was an extension that made the CPC IBM compatible. It should contain 512Kb memory and 2 x 5.25" disc drives.
So all in all You could run MS-DOS on the CPC. I guess it actually was a PC without keyboard and monitor. You could use the CPC keyboard and monitor.

Most of my CPC hardware, or more exactly nearly all of my Amstrad machines and other Amstrad hardware comes from Ebay.
But I think I was a bit ahead of the rest when it comes to purchasing retro equipment on Ebay. I bought it when prices was much lower than today.
A lot of it was purchased 5-10 years ago. Mostly on Ebay in the UK and Germany.
I did actually make a huge purchase when the Weeske warehouse was cleared years ago. Most of the goods went for decent prices, and I did also get a few private deals.


If there is any interest I could compile a list of ALL my Amstrad hardware, but practically everything I have is covered on the CPCWiki.


Yours

Terje Grind
NORWAY

It was an expansion card with the HD64180 CPU from Hitachi (Z80 compatible, but not for undocumented instructions. Has instructions like for multiplication though). Can be used for real time debugging and it has it's own memory. Kind of a CPC-Booster ;-)