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Tandy 3800 HD Repair/Restoration

I'm sure just about everyone here knows this, but for anyone that stumbles across this thread on a Google search, this is the style of RAM you need for a 3800:

TandyRam.jpg

The holes must be in the upper most corner of the SIMM, with hardly any PCB around them. There ultra low profile SIMMS are the only ones that will fit comfortably in the slots.
 
NOW...

Finding the 35 Pin RAMs for the 2810/20...

THAT is the hard part! :crazy:

:D

Well, since I no longer have a 3800 (AND allowed myself to ebay ANOTHER 2810hd) ... I guess I'll bow out.
:(

EDIT:
Before I go... Trivia question: What is the blank spot for?
 
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...(AND allowed myself to ebay ANOTHER 2810hd)...

LOL :lol: So, you were the guy that outbid me! That is just too funny! Well, I'm glad I only put in the absolute minimum bid and didn't counterbid once you put in the higher offer. It is going to a good home.

Will you have a full 5 MB of RAM now with the two additional 35 pin SIMMs from that machine?

Before I go... Trivia question: What is the blank spot for?

The blank spot is where the chip would be if they were parity SIMMs, non-parity SIMMs always have that blank spot. Easiest way to tell the two apart.
 
LOL :lol: So, you were the guy that outbid me! That is just too funny! Well, I'm glad I only put in the absolute minimum bid and didn't counterbid once you put in the higher offer. It is going to a good home.

Will you have a full 5 MB of RAM now with the two additional 35 pin SIMMs from that machine?


The blank spot is where the chip would be if they were parity SIMMs, non-parity SIMMs always have that blank spot. Easiest way to tell the two apart.

KEEEEEEY-RECT!!! :D

Im not... I was in a major panic that 'the other guy' would run me up to my accepted limit ($40) and then bow out.

Nope... that will be the ONLY pair I will have. I HOPE to reverse-engineer them and eventually be able to provide 'reproductions' to those of us who need them!
*wringhandsgreedily.jpg*
:p
 
Actually reproductions of those Ram card should be fairly simple aslong as you find the chips or compatible chips since its just a board... with chips... cut to shape with pads on the bottom... very simple... So find the data sheet on the chips and find out if they A: still produce them B:have compatible newer ones shouldn't be hard at all! and as for the board itself... should only be double sided right? so just... follow traces... design it in a board software like eagle? I could do that pretty simply!
 
KEEEEEEY-RECT!!! :D

Im not... I was in a major panic that 'the other guy' would run me up to my accepted limit ($40) and then bow out.

Nope... that will be the ONLY pair I will have. I HOPE to reverse-engineer them and eventually be able to provide 'reproductions' to those of us who need them!
*wringhandsgreedily.jpg*
:p

I just find this so hilarious! The question the guy answered and put in the Q/A section for the auction was my question; I wanted to find out what the RAM total was so I'd know if it was fully populated. I'm really glad I didn't put in another bid and it absolutely went to the right person. If you can reverse-engineer them that would be awesome! It honestly never even crossed my mind that you might be the other bidder. In the future when any of the Tandy laptops have more than one bidder, I'll have to send you a PM here to make sure I'm not bidding against you. I'd happily bow out and have you take the machine since you've been so cool.

You have any interest in a 1500 HD that works perfectly well except for a dead floppy and HD? I might have one for free, and I'd pay the postage. I should know shortly what is its fate. Unfortunately, it doesn't have the RAM card, nor the modem.

We should either start a new thread, or rename this one, to have a dedicated thread where Tandy laptop aficionados can pools their info/resources/coordinate.
 
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Either of you ever come across one of the Tandy external 5.25 1.2 MB floppy drives (25-1087) that are compatible with the 3800? There is not only very little information on them, but I haven't even seen one for sale anywhere, and it seems like there are more than a few people looking for them.
 
I just find this so hilarious! The question the guy answered and put in the Q/A section for the auction was my question; I wanted to find out what the RAM total was so I'd know if it was fully populated. I'm really glad I didn't put in another bid and it absolutely went to the right person. If you can reverse-engineer them that would be awesome! It honestly never even crossed my mind that you might be the other bidder. In the future when any of the Tandy laptops have more than one bidder, I'll have to send you a PM here to make sure I'm not bidding against you. I'd happily bow out and have you take the machine since you've been so cool.

You have any interest in a 1500 HD that works perfectly well except for a dead floppy and HD? I might have one for free, and I'd pay the postage. I should know shortly what is its fate. Unfortunately, it doesn't have the RAM card, nor the modem.

We should either start a new thread, or rename this one, to have a dedicated thread where Tandy laptop aficionados can pools their info/resources/coordinate.

The only reason I bid on it was for the RAM... and I expected to have the extra $$ from a sale I was doing.
I already have a 1500 and am not interested in another one. Thx tho!

Im hoping that since it has extra RAM, it might also have the math chip... he was unable to say YAY or NAY...
:D
 
Are the 287 math co-processors hard to come by?

20 years ago I had a 2810/60 that had all four SIMM banks full. If only I had known how rare they would become...
 
Uhm the Co-processors are sold on ebay accually but they are asking about 50$ for one!!!
Also Paralel I know it may be rude of me to ask but may I have the 1500 HD?
I'd LOVEEE to expand my tandy collection!
I would even pay the shipping if you had a way for me to pay you for it!
Also I will look into making repo ram cards for everyone!
I'm into so much stuff right now but I'll do research!
If someone can post images of the cards with maybe a ruller against it for dimensions? (make sure you have front and back and that I can see the chip numbers!)
So yea.
 
Are the 287 math co-processors hard to come by?

20 years ago I had a 2810/60 that had all four SIMM banks full. If only I had known how rare they would become...

20 years ago I had a totally tricked-out 2810 with a 120Mb drive in it... WORKING ACAD 10, with a PERFECT battery...

Yes... it would be easier for me to change sex than to find 387XLT-16 math chips... so far at least.

(Not that I would want to... of course! ) :cool:
 
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Uhm the Co-processors are sold on ebay accually but they are asking about 50$ for one!!!
Also Paralel I know it may be rude of me to ask but may I have the 1500 HD?
I'd LOVEEE to expand my tandy collection!
I would even pay the shipping if you had a way for me to pay you for it!
Also I will look into making repo ram cards for everyone!
I'm into so much stuff right now but I'll do research!
If someone can post images of the cards with maybe a ruller against it for dimensions? (make sure you have front and back and that I can see the chip numbers!)
So yea.

I think you will find that the math chips you find on ebay are NOT designed for our use... they are much smaller than those on typical 386 machines, and even the 3800...
Do you do a lot of board designing? I had some not-quite-complete designs done in FREEPCB but unfortunately lost them (and an electric vehicle design) during the SDisaster of 2012.
:p

EDIT: IF it IS the CORRECT device for a 2810... I would consider $50 for it... tho I would prefer... oh... 4 or so of them... :rolleyes:
:D
EDIT (again): When you're right... you're right! There seems to be a listing for 2 that should work... waiting to hear back!
Perhaps I need to buy some dresses... :lol:
 
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Heh I knew i found some on ebay before ALSO if you have pictures of the ram I will make boards and source parts!
I've done board design and eching before!
 
Actually reproductions of those Ram card should be fairly simple aslong as you find the chips or compatible chips since its just a board... with chips... cut to shape with pads on the bottom... very simple... So find the data sheet on the chips and find out if they A: still produce them B:have compatible newer ones shouldn't be hard at all! and as for the board itself... should only be double sided right? so just... follow traces... design it in a board software like eagle? I could do that pretty simply!

Yes, but w/o the chip number, one can only find something that fits the low-profile board and then attempt to wire it up. I fear that I will find the chips are a special production run by Panasonic (or their supplier) and that they stopped making them once the 'need' expired.

I remember paying a premium for those 4 RAMs... but they sure made AutoCAD FLY!!!
... if only it would RUN now. :(

I will have 2 once the 2810 arrives... hopefully the markings have not been lost from all the chips.
I too have done etching... but I suspect that I would leave the actual production to a company that specializes in that...
:D
 
Uhm the Co-processors are sold on ebay accually but they are asking about 50$ for one!!!
Also Paralel I know it may be rude of me to ask but may I have the 1500 HD?
I'd LOVEEE to expand my tandy collection!
I would even pay the shipping if you had a way for me to pay you for it!
Also I will look into making repo ram cards for everyone!
I'm into so much stuff right now but I'll do research!
If someone can post images of the cards with maybe a ruller against it for dimensions? (make sure you have front and back and that I can see the chip numbers!)
So yea.

Not rude at all. It's not like its doing me any good. As soon as I know for sure what its fate is, it's all yours Conmega, for whatever is the cost of shipping.
 
My 2810 has a math coprocessor and ndiags detects it and passes the test.
I certainly don't need it, so it's available. math co.jpg
 
Not rude at all. It's not like its doing me any good. As soon as I know for sure what its fate is, it's all yours Conmega, for whatever is the cost of shipping.


A favor if you please...
Pop the memory cover off the 1500 and tell me how many jumpers are on the pins to the right of the memory? and what orientation?
(2 both horizontal, 2 both vertical, 1 lower horizontal, 1 left vertical, etc)

I would appreciate it! The 1500 I have constantly acts like the internal battery is dead but it was replaced... well, recently. I think the jumpers there have something to do with it.

Thx!
 
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