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kemmer
October 27th, 2008, 04:36 PM
I have had this thing for a few years but I have never done anything besides turn it on.

I believe it's a Kaypro 2x, is that right? Anything else I should know about it?

Here's the problem. It used to power up and ask for a boot disk, now the power light comes on along with the drive A light, but that's it. I can hear something whirring, sounds like maybe the floppy drive. I opened it up to take a look an noticed that the reset button had fallen apart, so I found the pieces and put it together minus the spring. I wiggled all the cables, nothing. The neck on the CRT is glowing, so I'm guessing the monitor isn't the problem.

Anyone know what might be going on? I have a DMM, I just have no idea what to check for.

Sorry about these horrible pictures, my wife has the camera, I'll take some better ones when she gets home.
http://i3.photobucket.com/albums/y64/Kemmer/IMG_0023.jpg
http://i3.photobucket.com/albums/y64/Kemmer/IMG_0024-1.jpg
http://i3.photobucket.com/albums/y64/Kemmer/IMG_0025-1.jpg

Sharkonwheels
October 27th, 2008, 07:36 PM
More than likely, that is an '84 or so 2x. If you pop off the top cover (4 screws on L/R sides, and 2 on top) the RAM will be in the front left corner, and socketed. On the right edge of the mainboad, front to rear, there should be the FDD connector, then a 50-pin connector (may NOT have a header, and just be holes) then the power connector. Boot ROM should be just left of center, white sticker on chip, and might have 81-292 or 81-292A on it. If all the above is true, it's an '84, or at minimum, an '84 mainboard.

if RAM is front left, soldered on, then it's probably an '83, which would mean the 50-pin connector on right edge would NOT be there, between the FDD connector and the power connector.

2x was basically a DS/DD 2/83 or 2/84. Swap out the the 2's ROM, FDD's, and use the proper DS/DD CP/M, and it's a 2x. Which is basically the same thing as a 4. Which is basically a 'New 2' or Kaypro 1.

They were always throwing curve balls, trying to make things LOOK different, when they were actually the same.

here's my 10 '84 motherboard to compare to - you can see the 2 x 4 rows of socketed RAM front left:

http://i92.photobucket.com/albums/l33/Sharkonwheels/Vintage%20Computer%20Stash/IMG_0891.jpg


T

kemmer
October 30th, 2008, 06:38 AM
Thanks for the info! Does anyone have any ideas about why it won't turn on?

Terry Yager
October 30th, 2008, 09:10 AM
Thanks for the info! Does anyone have any ideas about why it won't turn on?

My first guess is always bad solder joints on the power supply, since I've seen so many Kaypros fail for this reason. Check around the input and output pins, that's usually the ones that go bad.

--T

Druid6900
October 30th, 2008, 11:19 AM
My first guess is always bad solder joints on the power supply, since I've seen so many Kaypros fail for this reason. Check around the input and output pins, that's usually the ones that go bad.

--T

T, do these suckers have a flyback that is mounted vertically in the case, like the old Apple 128, SE, Classic etc.?

Seems, from the original post, that the unit powers up, just no video display. You may be right about the bad solder joint, but, it may be on the flyback.

If it is possible to disconnect the reset button, I'd do that too, as, without the spring (which I'll assume is used to break contact) it might be continuously resetting itself.

Terry Yager
October 30th, 2008, 12:46 PM
The video runs on 12v, so if one or more 12v pins is loose, it could explain why there was vid, but none now, after moving/setting it aside for awhile (and if ya kick it real hard it might light up again). I've seen that symptom quite a few times.
Yah, definitely wanna fix that reset switch too.

--T

kemmer
October 30th, 2008, 09:49 PM
My first guess is always bad solder joints on the power supply, since I've seen so many Kaypros fail for this reason. Check around the input and output pins, that's usually the ones that go bad.

--T



Cool, I'll check those out this weekend.