Image Map Image Map
Page 1 of 2 12 LastLast
Results 1 to 10 of 20

Thread: What the heck does this switch on my kaypro2000 do?

  1. #1
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    224

    Default What the heck does this switch on my kaypro2000 do?

    so there is a small slide switch located behind the left lcd hinge on the unit. See photo. What does it do? its near the power input and battery lines so I assume something with power or charging but what? I have two battery packs (the internal and the options external pack that came in a canvas pouch) which still manages to hold some juice. I just want to try and see if the unit has any life. I kind of get the feeling some tantalum caps may have already blown.

    Anyway, what the heck does this switch do?kp2000 switch.jpg

  2. #2
    Join Date
    Jan 2013
    Location
    Marietta, GA
    Posts
    2,168

    Default

    Press it and find out

    Is that actually a button?

    I just looked at mine and mine does not have that. However, a little further behind that should be a lever switch that is engaged when the screen is placed in the "up" position. That is what powers the system on/off. It could be someone wired in an extra switch to act as a reset, or perhaps allow it to run with the the screen down.

    BTW, does yours still have the lead battery pack? Mine does, the battery is dead but it just doesn't feel like the good old heavy kaypro without.

  3. #3
    Join Date
    Nov 2012
    Location
    Richmond Hill, Ontario, Canada
    Posts
    894

    Default

    I don't know what the switch does but I have two Kaypro 2000s (neither had a power supply so I have never powered them up ). Anyway, one has the same switch but the other does not. Interesting that some have them and some don't.

  4. #4
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    224

    Default

    this youtube video makes mention of the switch. https://www.youtube.com/watch?v=pXpbQEtIafU

    so anyway, my kaypro 2000 didnt have an AC either... (how can there be all these kaypro laptops with no AC adapters?)

    I bought the external battery pack off ebay (comes in the cloth case) I am using my fathers old 1970's era Sears automotive battery charger since it has a 6 and 12 volt option and 1.5 or 10 amp switch too. Im using 6 volts at 1.5 amps to charge the external batttery pack. After 30 something years, It holds a slight charge.. Today for the first time I was able to see it post! it boots, counts the 640KB Ram, Bios rev and date are 1.08X 11-14-1985 it then says no valid boot disk is inserted and clicks a couple times asking for a boot disk and to push any key to continue. Oh yeah, this unit came with the original disk spacer for the floppy drive!
    SomeGuy my kaypro 2000 still has the internal batteries. I want to pull them and see if I can wake htme up with the charger too. Does anyone know what the exact power supply specs should be?

    I dont know about this switch, I cant imagine half of the ones out there were modded. I think they came that way. Its bizarre.

  5. #5
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    224

    Default

    forgot to mention the LCD is so dim! I have to use CTRL-ALT-F2 a few times to make the contract darker but it is still dim at its darkest setting! ?Hope there is a way to fix that.

  6. #6
    Join Date
    Jan 2013
    Location
    Marietta, GA
    Posts
    2,168

    Default

    Unfortunately, my power supply has no markings on it. It looks like it had a paper label on it at one time but it fell off a long, long, time ago. That is probably why the power bricks get lost - nobody knows what they are for and they don't fit in the carrying case.

    Ah, so you snagged that external battery off of ebay. I was thinking about grabbing it myself, but the last time I tried to power up my Kaypro 2000 something else had gone wrong with it. It looks like that is the same battery they used internally, so if your internal battery is dead you might be able to swap it.

    The power supply is a simple DC power brick. I THINK it is supposed to be ~5 volts DC, but when I tried to measure mine I got some odd results. I think it needs a load on it.

    Actually - test you external battery after it is charged and see how much voltage it is putting out.

    A word of warning: The Kaypro 2000 internals have NO protection against too much voltage or negative voltages. So if you get the voltages wrong, you can smoke the entire thing. Someone on Youtube did that. I'm not even sure if there is any power regulation inside.

    The internal battery itself is just wired directly to the DC power. No circuitry other than a fuse!

    Nope, the LCD screen is just plain dim. I think some of the much later models had a backlight. All you can do is position the laptop against some good lighting.

  7. #7
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    224

    Default

    yeah Im the one who got it off ebay. Told the guy I wasnt gonna pay anywhere near full price because the cells are 30 something years old. I got it for a fair price.
    well its been charging for a few hours and its putting out 6.05VDC according to my fluke. Ill try some trickle charging tomorrow too. the batt was pretty warm as well.

  8. #8
    Join Date
    Jan 2013
    Location
    Marietta, GA
    Posts
    2,168

    Default

    Ok, I tested my power brick with some different loads on it, and it reads a hair more than 6 volts (it reads much higher with no load, which is not right). Since there is no marking on it, I'm still not 100% confident, but that is close. The round plug has ground on the inner part, and positive power on the outer part.

    The kaypro 2000 user guide states "The KAYPRO 2000 operates from one of two power sources : an external 120V AC wall outlet, or the internal 7V DC battery pack.", so certainly no higher than that.

  9. #9
    Join Date
    Nov 2012
    Location
    Richmond Hill, Ontario, Canada
    Posts
    894

    Default

    This picture is from this Kaypro 2000 eBay listing. https://www.ebay.ca/itm/192357655428 That should answer the question. I have been looking for one for a while but I may just try a 7.5V 2A wall wart and see if that works (like this one https://www.ebay.ca/itm/3112361443737 ).

    Kaypro 2000 power supply.jpg

  10. #10
    Join Date
    Jan 2012
    Location
    Connecticut, USA
    Posts
    224

    Default

    Snuci, I just saw your post this morning but your second link ( https://www.ebay.ca/itm/3112361443737 ) says the posting was removed.. So I dont know what it was. Can you send another example. Id love to find some kind of power source for my unit.

    SomeGuy, are you saying the centerpost is negative??!! Thats stupid! I hate when they do that... didnt the round power port Vic20 also have that issue?
    the battery pack was down to 5.24VDC this morning, doing some more charging on it right now. The kaypro is on, connected to the ext battery pack. I have jumper leads connected to the battery packs break away connectors and that is where I clipped on the battery charger. its jumping around 6.5vdc right now. I havent taken the kp2000 apart to see anything yet so I dont know the charging circuit. I know everyone says its "nonexistant" but it seems there is no charging happening with the onboard battery pack. When I open this thing up in a few weeks Im going to try some high amp charging and see if I can wake it up or kill it in the process (who cares its most likely dead)

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •