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Elvi
November 23rd, 2011, 12:24 PM
Yes i actually have 2 Kaypro 2'83's, the first one is in full working order the other one has this litle problem when started up cold that i'd like to fix, images will show the problem.

warning images are rather big, around 1mb each.

1 (http://junk.aecweb.ath.cx/tmp/kay2/19112011079.jpg) this is what happens when it is cold booted.
2 (http://junk.aecweb.ath.cx/tmp/kay2/19112011075.jpg) this is what it's supposed to look like and it does look like this if you reset it or let it load a floppy funny enough.

the rest is just images of the innards for referance if nothing else ;)
mobo (http://junk.aecweb.ath.cx/tmp/kay2/19112011076.jpg)
left side (http://junk.aecweb.ath.cx/tmp/kay2/19112011077.jpg)
right side (http://junk.aecweb.ath.cx/tmp/kay2/19112011078.jpg)

i have soldered a plug on it's power supply and that fixed up some of the bugs but not this one, so if any of you oldies out there have ever playd with these things before or you know some tricks to test just let me know, i might sell this one eventually but the other one is MINE! :P is MINE!

i know for a fact that the us and europe have a differance in the naming of this kaypro, the us has II and the europe 2 or 2'83, the chips on mine say 1983 and the ports on the back match up with the us version.
heres a page with the working kaypro 2 i have for referance.
http://electricdreams.ath.cx/comp/kaypro2.php?current=2&s1=1

GADFRAN
November 23rd, 2011, 05:12 PM
Elvi,

First – a hearty welcome to this web site – keep posting and you can become a professional member.

We are a very friendly and helpful bunch, just interested in keeping this hobby alive.

I took a quick look at what you sent. Good job ! So many do not include so many details and pictures.

I initially offer the following, since I know you must be anxious to solve this issue.

================================================== =============

Be aware that there can be no liability in any way for any information given – if you use the information, then you accept this, otherwise, just do not use the information. Things are just too complex and many things can happen, some lethal, especially for those who are not familiar with such matters.

This may not be mentioned, but it is my policy, so I mention it here

================================================== ======

In trouble shooting, it is usually good to just start with the “ simplest things” first.

At first glance, I have gotten a similar screen pattern on startup. What I found was that it was a loose chip – usually one of the big ones – the Z80’s.

U43 is the character generator Eprom, so you can check that also.

The Kaypro technical manual may also give some clues – see below for a free source on the internet.

I pressed firmly on each one – not too hard to crack the mainboard, but very firm and for about 5 – 10 seconds.

Although there seemed to be no movement, when I turned the Kaypro back on, I had the proper screen.

At least you have a second Kaypro to compare too.

Many times socketed, like your Kaypro, as opposed to soldered in chips get loose or corroded, not visible, but enough to not make good connections.

Also, Kaypros are portable, so they get knocked around a lot and that can loosen socketed chips.

================================================== =============================

The web site in Great Britain “bitsavers” has free downloads of the technical Kaypro manuals + voluminous other computer info. Download the technical manual and you will find it very helpful in many ways, especially in the future.

It will indicate that you may really have a “ 1983 Kaypro 4 “ – mainboard 81-232 and ROM chip at U47 81-232, if there is a printed “ A “ on this chip – usually in red.

Micro Cornucopia information confirms this, but the Kaypro technical manual indicates yes you could have a 1982 Kaypro II [the number “2” was not used then at least here as you even note.

Are your Tandon [picture indicates could be usual Tandons] disk drives SSDD or DSDD – Kaypro 4’s have the DSDD and Kaypro II’s SSDD.

This may not make much of a difference now, but in the future, it is a good thing to know.

================================================== ==================

All of this is very confusing for many reasons, including Kaypros in other countries, and we are gradually tracking it down. Search this site for much more information on Kaypros and the Kaypro registry we have started – but it got so complex – it is on hold for now.

================================================== ========================

Picture of the back of the Kaypro can be helpful, also along with the serial number and other information on the back, besides the port configuration you even mention.

Any history of these Kaypros would also help for clues – it can get like a murder mystery sometimes – but once solved, it was so obvious after, but not while you are trying to solve it.

I am sure you will get more replies from us “oldies” – we always try to help and are most interested – to keep the Kaypros running but also one less computer going to the landfill.

But in this country it is the Thanksgiving holiday weekend, so any replies may be delayed.

Check my very simple initial website [which will be improved in the near future] WWW.KAYPROSTS.ORG [STS = science, technology and society – my decades of research in this area] under the “Special “ folder for a draft of my Kaypro book and a 2008 Kaypro Calendar for some other information and some pictures.


Please report back to us so we can continue to develop our Kaypro knowledgebase on this site.

When I have a chance to think about your situation more, I will post again.

Thanks !

Good luck !

Frank

Elvi
November 23rd, 2011, 05:49 PM
the u47 only has 81-232 on it but the chip at u43 has hand writen 233A on it and the cpu is actually a mostek z80 not a zilog like in the other computer.
the mainboard has printed on it PC81-240 A.

the floppy drives i think are SS/DD as they don't handle more than 191Kb

actually i just went and did a 5 sec test on each socked chip, nothing changed and for some reason i had more trouble getting the kaypro to boot up right this time, not untill it got warm did it show the right picture.

heres more pics of it's back even with serial, bad comps serial 143526, good comps serial 107533.
http://junk.aecweb.ath.cx/tmp/kay2/24112011081.jpg
http://junk.aecweb.ath.cx/tmp/kay2/24112011082.jpg
both kaypros are almost identical except for the cpu and some other cpu chips.

Lorne
November 23rd, 2011, 07:33 PM
Elvi,

The web site in Great Britain “bitsavers”
Frank

Is Bitsavers.org really in Great Britain?
I didn't realize/know that.
Their website shows as being hosted in the US.

tezza
November 24th, 2011, 05:33 PM
1 (http://junk.aecweb.ath.cx/tmp/kay2/19112011079.jpg) this is what happens when it is cold booted.
2 (http://junk.aecweb.ath.cx/tmp/kay2/19112011075.jpg) this is what it's supposed to look like and it does look like this if you reset it or let it load a floppy funny enough.


Hmm...I wonder if something in the video RAM circuitry is touchy and maybe comes right after a bit of warming up?

Tez

GADFRAN
November 24th, 2011, 07:02 PM
That may be a "mirror" - but please let us all know - so much "misinfo" out there.

Different copyright laws than in US so that may be why they can do what they do.

Chuck on this site knows a lot about this.

Chuck - let us know !

Thanks !

Frank

GADFRAN
November 24th, 2011, 07:03 PM
Just a quick reply, since you are so interested !

Will think about it more, especially as you give more info & pictures – latest pictures super – thank God for digital cameras and email attachments !

================================================== =======

Ah, the “murder mystery continues !”

Do not be discouraged, we all have gone thru this many times with Kaypros !

The big thing here is that you document well – that helps a lot.

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Necessary background info -

In my Kaypro book I note that Kaypro was in a “ great disorganization “ for many reasons, since it had so many products and was going into bankruptcy – “hypergrowth” as Osborne said.

It was totally chaotic – statistics – every 5 – 6 minutes a Kaypro was assembled, tested, shipped, etc. – over 50,000 a year – 20,000 Tandon disk drives per month, etc. - you do the math – who can manage that ? especially in the 1980’s ? - many already paid for – why Osborne went under, etc.

================================================== ===============

So just what Kaypros were produced under such conditions ? We are now finding this out.

Simply – all 1983 Kaypro II’s even are not the same ! Check many past posts on this site for numerous examples.

Tez in New Zealand has a Kaypro 4 with a modem – S/N around only 5000 – not standard – my pictures of my Kaypro 4 has no modem S/N in 100,000 ‘s – back of it picture – will post it in future – compare it to his - many stories to tell.

They even “ disguised “ computers in New Zealand / Australia to look like the more popular Kaypros [see past posts] !


“ Immediate practical suggestion “

–“ the simple ice cube trick “

– since you said you are interested in Kaypro tricks from us “oldies” as you call us – hey, I am no 70 and proud of it – I survived this long, but how much time do I have left ? Who knows and who cares, but I am going to make the most of it – “ I earned it, I deserve it and I am going to get it, if I have anything to say about it “ – as the saying goes ! Many other “oldies” on this site – but how do we get the younger ones interested for when we are gone ?

But you sound young ! How old are you + any more info you want to share about yourself would help us all in dealing with you, especially technically.


Simply – you put an ice cube in a plastic bag, so the moisture does not contact a chip – you put the ice cube in the plastic bag on each chip to cool it to see if that chip is the one that is not behaving right when it is cold – at startup !

Obviously, you can do the reverse – heat a chip to see if it then makes the Kaypro work correctly – heat – your choice – any hot item, etc.

================================================== =============

So what ?

Well you have another working duplicate Kaypro to “ swap chips “ – big advantage - but one thing at a time – that can be tricky – more info later.

Also, believe it or not, some of the basic Kaypro chips are still available for only a few dollars - as opposed to multiples of $10 in the 1980-90’s – e.g. Jameco in USA – check your local options – but still export restrictions here for some reason.

But that was another reason Kaypros so popular – off the shelf parts – faster production – 50,000 a year – see above - but disaster for IBM, since made clones more readily available.

Obviously, Kaypro had some proprietary chips, but with the glut on the market, you can pick some Kaypros up for just shipping or $50 - $100 in USA and swap the few proprietary chips, if necessary + have a good stockpile of spare other parts.

But in over 20 years of heavy use, our six [6] Kaypros have had few chip issues unless they were associated with me modifying the Kaypros to “ exceed “ their original design specification – e.g. Micro Cornucopia upgrades, etc.

================================================== ================

We are starting to get into “ deep stuff “ here, so just concentrate on the simple basics first, but wanted you to know of the possible options for the future that make Kaypros so attractive to the vintage computer interests compared to other vintage computers.

================================================== ================

Hope this helps !

Please report back ! If you have this issue, others have or will have.

We do not have Kaypro, Micro Cornucopia, etc. to ask – they are long gone – it is only us to try to preserve all this history for the benefit of others in the future.

Our evolving knowledge base on this web site is all we have and all need to contribute.

You are the first Kaypro user from Finland on this site – I had no idea Kaypros were in your country – where else in Europe and the rest of the world – even found out very popular in Africa for missionary work – more info if interested..

How many other countries in your area of the world have Kaypros ? We are now finding out if ever so slowly.

It was the way that many computer companies tried to survive by expanding outside of USA – but much undocumented – do searches on this site for Netherlands, Canada, Germany, New Zealand, Australia, England, etc. on Kaypros there.

Fascinating !

Thanks !

Frank

P.S.

Rushed since you are so interested, so please excuse any “typos” – my wife is an English major and they get very upset about “typos” !

Also, we do not really have much of a family left anymore, so I have more time to devote to such detailed responses over the holidays than others who have larger family responsibilities.

GADFRAN
November 24th, 2011, 07:04 PM
Thanks Tez for your always "espert" opinion - much appreciated - see my reference to you above !

Frank

Elvi
November 24th, 2011, 07:23 PM
to start with i'd not rather "poke" around with the chips in the working one if i don't need to and now that i think about it i actually had loose the bigger socketed chips including the mostek cpu, they were stuck good in there but it didn't help to reseat them, that was a few months ago i think when i first got ahold of these kaypros.

i'm 30 btw, born 1981, my first ever computer was a used breadbin c64, i still got it and in fully working order, or atleast it looks like that, with 1541 drive and cassette drive.
btw that last url i placed in the first post contains alot of old computers even pc's all collected by me :D i have a interested for computer hardware if that hasn't come out yet... ah i just remembered what i got with the 2 kaypros, look here at this link :)
http://electricdreams.ath.cx/hd/rodimer0204e.php?current=3&s2=2 and look especially at the note there ;)

ah maybe someone of you know what this card is for, it's 1 of the few things i've not figured out, came with the same batch.
http://electricdreams.ath.cx/unknown/panda.jpg the info is on this page with some other parts http://electricdreams.ath.cx/unknown.php?current=3&s2=8.

GADFRAN
November 24th, 2011, 07:28 PM
7194Tez,

Been very busy with many projects and wanted to get you a picture of "my" Kaypro 4 compared to yours - very different and yours much lower S/N - the complexities - see attached.

Frank

Elvi
November 25th, 2011, 08:19 AM
interesting i actually think the last owner also had a bunch of kaypro 4's but they were sold off when i got these 2 off him.
btw my kaypros has been in the newspaper buisness, the fully working one even has the old newspaper logo on the keyboard heh.

tezza
November 25th, 2011, 12:00 PM
Tez,

Been very busy with many projects and wanted to get you a picture of "my" Kaypro 4 compared to yours - very different and yours much lower S/N - the complexities - see attached.

Frank

That is one customised Kaypro 4 Frank!

Tez

Elvi
January 1st, 2012, 07:08 AM
ok so i finnaly got around to trying the "chill" test on all chips, when i get to around u47-u49 then it doens't help to press the reset button multiple times, and just before i write this i retested u47 and does seem to be ok while placing the ice on u49 i can't get the grabish text to go away untill i warm it up with a finger.

so how to go from here... u48 is soldered to the board while u47 and u49 is socketed, should i bend loose u49 and see what happens or what? if bend loose then how in a gentle way, last time i tried i used a flat screwdriver and gently pulled it loose.

Elvi
January 4th, 2012, 09:21 AM
reseated u47 and u49 but it's still the same :(

Elvi
January 4th, 2012, 11:11 AM
another update, i figured i just should and try to switch the u49 chips betwen the kaypros and to my surprice they both worked so i switch back and the troublesome kaypro continues to garble the screen :confused:

tezza
January 4th, 2012, 01:40 PM
Hmm...I wonder if the socket is faulty. Faulty sockets in old machines have caused me all kinds of grief. Sometimes they work, sometimes they don't.

Just put a bit of pressure on the chip (or various areas of the chip) with your finger as you boot up. See if this does anything.

Might pay to check the signals coming off the chip in the faulty machine to see if they reveal a socket leg not making correct contact.

Tez

Todd82TA
January 4th, 2012, 02:56 PM
No way!!! A thread about Kay Pro computers! That's awesome.

My first computer was a Kay Pro PC-10. It was a DOS clone, with an NEC V20 processor, 768 memory (640k base, and an extra 128 used for a ram-drive). It had dual 360k floppies, and a Seagate ST-225 RLL hard drive. My first game was Starflight, and I played that with the monochrome monitor. I'm really not one to collect a lot of junk or clutter, but I saved that computer since it was my very first computer. My parents bought it when I was only 7, and I never let them get rid of it.

Some time ago, a relative gave me a KayPro 2. I don't know much about it other than that it's a CP/M system. It works awesome. Like I said, I'm really not one to collect stuff, but I kept it only because I was such a fan of the Kay Pro make because of that PC. The quality of those machines were awesome. I actually tried to give it away a few years ago, and no one wanted it. I've since moved four states away, and now it's sitting in a storage unit in Florida (climate controlled). I probably won't get to it for another 6-7 years, but I'd give it to you for free if I had access to it... heh.

A few... man... wait... not a few, 11-12 years ago, I bougth a new computer... in 2000. The Kay Pro name had just come back under the parent owner Premio. I purchased a Kay Pro desktop for like 1,600 bucks. It was a Pentium 3-733 w/ 128 megs of ram or something... don't even remember. It was just a clone, not really much of a Kay Pro. Before I bought it, I actually looked up the original owner, Andy Kay I think was his name. He owns (or owned at the time) a computer company called Kay Computers (no longer owned the rights to Linear Systems or Kay Pro). I ended up not getting a computer from him because it was just a bit more than I wanted to spend... but man... what times.

I love my KayPro PC-10...


... I just looked it up. It looks like Kay Computers is out of business... :( oh well.

Elvi
January 4th, 2012, 09:27 PM
Hmm...I wonder if the socket is faulty. Faulty sockets in old machines have caused me all kinds of grief. Sometimes they work, sometimes they don't.

Just put a bit of pressure on the chip (or various areas of the chip) with your finger as you boot up. See if this does anything.

Might pay to check the signals coming off the chip in the faulty machine to see if they reveal a socket leg not making correct contact.

Tez

i actually did that while testing and sometimes it helped, did also put a flat screwdriver between the mobo and the socket as there was a tiny bit of room and it moved slightly, don't know if they should do that or not but i'm thinking it's a cold solder on that socket and i don't really have the right equipment to fix that, too big a soldering iron :( and i only have a volt meter so i doubt i'd get anywhere with that on checking the chip + i'm not very smart when it comes to this type of tech stuff, i can handle it if i can fiddle around with the stuff but that's about it, doens't mean i don't like to collect these old things, curiousity killed the cat eh? :D

tezza
January 5th, 2012, 01:05 AM
i actually did that while testing and sometimes it helped, did also put a flat screwdriver between the mobo and the socket as there was a tiny bit of room and it moved slightly, don't know if they should do that or not but i'm thinking it's a cold solder on that socket and i don't really have the right equipment to fix that, too big a soldering iron :( and i only have a volt meter so i doubt i'd get anywhere with that on checking the chip + i'm not very smart when it comes to this type of tech stuff, i can handle it if i can fiddle around with the stuff but that's about it, doens't mean i don't like to collect these old things, curiousity killed the cat eh? :D

Well if it helped sometimes, that's further evidence that it might indeed be a dodgy socket.

It's actually not that hard to do. You don't have to replace the socket...just identify the chip leg that's not making a connection and solder from that leg, to a point on the board where the corresponding (and probably faulty) socket cell is suppose to connect to. Similar to what I did with a faulty socket here.

http://www.classic-computers.org.nz/blog/images/2010-09-06-kaypro-ram-socket-fix.jpg

To find out which individual socket cell is at fault, use a circuit diagram to see what nearby point on top of the board each socket leg is connected to (before it goes through any components). With the chip inserted, test for connectivity from the top of each leg of the chip to this point. There should be full connectivity (0 ohms). If there is no connectivity and the circuit diagram says there should be, you've probably found the problem. Push gently against the leg with the probe to see if connectivity suddenly occurs. If it does, that's further proof that the connection is faulty.

Jumper it like I did. You will need a electronic soldering iron but nothing fancy. They cost very little and are a must if you're keeping any kind of old computer collection.

Good luck!

Tez

Elvi
January 5th, 2012, 02:07 PM
i've actually tried to resolder the socket now with litle success, at first i just reheated the old solder but that just made it worse, like the chip wasn't there at all so i applied new solder and i'm back where i started :P

from what i know my soldering iron isn't electronic, you just have 1 power cable to it and you plug it into the wall mount and that's it, it's 60w btw.

i tried to check legs atleast by looking where the leads go too and always seem to get 5ohms so i don't know what that suggests, i did however bye 2 new 20pin sockets today if i needed to change it + a solder vacuume.

tezza
January 5th, 2012, 02:31 PM
Hi Elvi,

Changing old sockets can actually quite difficult. It's really easy to lift tracks up (and break them) when you try to take the old socket out...especially when the tracks are on both sides of the board. I'm not sure that's the case on the Kaypro.

This is why I suggested leaving the socket in and just jumpering the faulty cell to where is should go (although reflowing the solder on the base is always a good idea too...but doesn't always solve the problem in the socket cell itself is damaged).

However, If you are not used to soldering my advice would be not to do any right now. Particularly with a soldering iron of that wattage. You are likely to damage the board. Something between 15 and 30 watts is what you need for an electronics soldering iron.

Elvi, I'm not sure how familiar you are with electronics. Do you not have a circuit diagram for the Kaypro and if so, can you read it? Are you familar with how a multimeter works? If you are not sure, I would leave this project and learn some of those principles first perhaps by doing a simple kit or so. Certainly I wouldn't go near my Kaypro with a 60 Watt iron. I think my own soldering iron is about 25 watts.

Tez

Elvi
January 5th, 2012, 03:19 PM
i havn't changed the socket yet but what done is done now, and it's not like i hold that iron there for long, maybe 2 secs at most just to add more solder, anyway from the diagram at bitsavers, i tested the legs of u49 and everyone of them gives a litle ohm reading to both the cpu and the eprom, did the same test on the working kaypro and got the same ohm readings, between 2 and 5 ohms so i guess there is contact on the legs, did it with the chip in place btw.

i'm somewhat familiar with electronics as i learned household power in a school and got a nice multimeter from there with alot of settings, i know household power and electronic power ain't the same thing but they are related.

hers what the underside of the board looks like when i've been at it, hope it isn't too bad
7519

and my multimeter and solder iron just to show you what i got.
75177518

tezza
January 5th, 2012, 03:44 PM
i tested the legs of u49 and everyone of them gives a litle ohm reading to both the cpu and the eprom, did the same test on the working kaypro and got the same ohm readings, between 2 and 5 ohms so i guess there is contact on the legs

Not necessarily. It depends which way the circuit is going to get to the CPU. It could be going through the IC and out another leg to get there.

Use a circuit diagram to see exactly where the track from each socket goes. Follow the track from the bottom of the socket to a convenient place to put a probe but before the track goes into any other component. Put one proble of the multimeter on this point and the other on the top of the chip leg. This should show a direct connection with etremely low Ohms.

You could still get a low reading if the circuitry somehow loops back through another part of the chip to that connection point so it's not necessarily definitive. One thing is for sure though. If it shows NO connection between the two probe points then you have found a faulty socket cell.

Tez

Elvi
January 5th, 2012, 04:06 PM
there is hardly any place like that at all, very few of the legs have any extra points and most goes to the next chip.

btw what did you think about the solder, was it badly done, i just gotta know :nervous:

oh and i don't understand the diagram at all with leg 19 on u49 and also i can't find u48 anywhere on the diagrams so i can't even test it right.

tezza
January 5th, 2012, 04:20 PM
The solder points don't look too bad. I still wouldn't risk a 60W iron though. You can heat up the board too fast and damage it.

Ok, as you have the board out of the computer anyway, with the chip inserted, just measure any resistance from the top of the chip leg to the corresponding solder point on the bottom of the board. This will see if there are any open connections due to a faulty socket cell.

Elvi, I've got to get off these boards now. Maybe someone else would like to comment.

Good luck with it.

Tez

Elvi
January 5th, 2012, 05:05 PM
all the legs from the top of the chip to the bottom of the board gives some resistance like 1 or so, seems my multimeter is a litle finiky but atleast it shows something.

i tried the other kaypros u49 chip again in this kaypro and hello!? it works, thats just weird even after i've chilled the chip with an ice cube in a plastic bag it still works... i'm starting to think that the cullprint is the u49 chip itself :( it works perfectly when it's warm but when it's cold the garbled screen appears.

Terry Yager
February 7th, 2012, 01:56 PM
How 'bout an update, Elvi? Joy yet?

--T

Elvi
February 7th, 2012, 05:31 PM
Nah nothing to report, i think the chip is screwie or something.

I pretty much gave up after the last test and screwed it together and put it away.