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fatwizard
September 4th, 2017, 08:55 AM
I picked up an 8bit memory card last week that will only fit in a 5150 slot. The daughter card is situated such that it bumps into the adjacent slot on a 5160. The slot cover bracket is double wide, like some early cards for the 5150 I have seen, but the bottom of the bracket ends in a curved tang unlike any I have seen before. All of my searches have come up empty on this card. Anyone know what system had slot cover brackets like this?

4060340602

eeguru
September 4th, 2017, 09:05 AM
I believe first gen Tandy 1000s (A, SX, TX) were wider than most. Might be a 3rd party clone for one of those.

mR_Slug
September 4th, 2017, 09:11 AM
Interesting card, no idea who made it/for what system. There is a possibility that someone bent the tang, instead of it being manufactured that way. I've had some cases that needed the tang manipulated as they don't align with the slot properly. It may also have been crushed, when screwed down.

SomeGuy
September 4th, 2017, 09:50 AM
Are there any markings on the main card? Perhaps post a picture with the daughter board removed?

Being not full-length does hint that perhaps it was designed for a specific smaller clone. Some early clones did use wider card spacing, or may have had one slot at the end that would have space for this.

It is also interesting that the daughter card seems to extend all the way down to the motherboard level. I would expect most daughter cards not to extend past the main card's fingers. This suggests they knew it would not hit any chips or anything in a specific machine.

Can you tell about when it was manufactured? What are some of the date codes on the soldered on chips?

keenerb
September 4th, 2017, 12:35 PM
Are there any markings on the main card? Perhaps post a picture with the daughter board removed?

Being not full-length does hint that perhaps it was designed for a specific smaller clone. Some early clones did use wider card spacing, or may have had one slot at the end that would have space for this.

It is also interesting that the daughter card seems to extend all the way down to the motherboard level. I would expect most daughter cards not to extend past the main card's fingers. This suggests they knew it would not hit any chips or anything in a specific machine.

Can you tell about when it was manufactured? What are some of the date codes on the soldered on chips?

Memory expansion for Mitsubishi Multi16 is my guess.

bob22
September 4th, 2017, 12:59 PM
As someone involved in the press tool industry, the pics seem to show that the tang ripple is a deliberate manufacturing feature rather than something that happened during assembly. I very much doubt that the screw thread tightening would be able to buckle it in that way.

fatwizard
September 5th, 2017, 01:00 PM
Memory expansion for Mitsubishi Multi16 is my guess.

I'm sorry to be slow in response, but much is going on right now. The Multi16 is a good guess since the card says "Memory Expansion I on the base card and Memory Expansion II on the daughter card, with both labeled "Mitsubishi Electric Corp.". It also has what appears to be model numbers. WEAM20 for the expansion card and WEAM21 for the daughter card. The bracket gives every appearance of having been made the way it is, and the daughter card dropping all the way down would indicate it wasn't meant to be installed in just any system.

I had never come across the Muli16 before, and am not finding much information on it either. No pictures of the inside of one that I can find. The info I have found indicates the Multi16 is a 16bit, 8088 based system. This card operates perfectly in a 5150 motherboard with 256K of onboard RAM. This card fills in to 640K. Since I have no idea how the switches work, it must have previously been in a 256K system, and on an 8bit bus.

Chuck(G)
September 5th, 2017, 06:08 PM
IIRC, the Multi16 doesn't use a standard ISA bus. It's very early and has its own peculiar interface.

However, the Sperry PC (1984) was very PC compatible and was made by Mitsubishi. Stock memory was only 128K, so a memory expansion would be logical.

Caluser2000
September 5th, 2017, 06:19 PM
Looks like a very nice memory expansion card.

fatwizard
September 5th, 2017, 09:49 PM
IIRC, the Multi16 doesn't use a standard ISA bus. It's very early and has its own peculiar interface.

However, the Sperry PC (1984) was very PC compatible and was made by Mitsubishi. Stock memory was only 128K, so a memory expansion would be logical.

Well Chuck(G), I think you have it right. By the look of the slot covers on the machine in this post;

http://www.vcfed.org/forum/showthread.php?53303-Error-on-recently-rescued-Sperry-PC

You can't see the bottoms of the brackets in the pictures, but they look the same as my mystery card from the top with the slots correspondingly further apart.

I think the mystery has been solved.

Chuck(G)
September 5th, 2017, 10:16 PM
The curious thing is that the Sperry/Mitsubishi PC had 7 ISA slots, but they were all wide ones.