apple iie problem

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Guys, I got another iie with some problems.

There's no power going to the disk drives on my bad iie motherboard. The disk drive indicator light does not turn on and there's no spinning in the drive so it does not get any power from the motherboard. I have checked the power supply and it has power going into the motherboard. I have searched through several tech manuals but have no idea which chip controls the power going to the 5.25 disk controller.

I have been trying to find out through reading tech manuals which chip on the motherboard gives the power to the disk drives but I just can't find it.

Doing a pr#6 will hang the computer.

If I try a self test, the computer will self test forever, the only thing that changes is the amount of beeps.

I have tried removing and reinserting all the socketed chips on the motherboard, to no avail. I did however find a small amount of corrosion on the motherboard which I retouched with new solder.

The only thing I suppose I can do with it is use applesoft basic. When I turn on the motherboard, I get the apple //e and the command prompt.

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speedyG's picture
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Re: apple iie problem

Hello insanitor,
sorry but i´m just on my way to bed when i checked out posting here.
Tommorrow morning i´ll reply entirely....
there are 3 points to check:
the 74LS138 that is used to switchon the interface card,
the interface card that shall control the drive
the analogboard from the drive.
I´ll set tommorow ( in 10 hours from now ) links for download of the circuitplans of this 3 unitparts.....
sincerely speedyG

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Re: apple iie problem

Aside from Speedy's suggestions, the only thing I could ask is have you tried different slots for the Disk ][ Card?

If so, do you get the same results?

Just a thought. Smile

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"Apple ][.....It's ALIVE!!!!!"

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Re: apple iie problem

Tonight, the results of what I was doing terrified me.

I found out that the drive controller card really was dead when all this time I thought it was ok. Still, when I put a known working card in there, it still won't work.

I decided to try something daring and put my Laser UDC card in it. That did not work either and I found out a few things about my UDC card.

It will not boot Copy II Plus 9.1 but will work with 7.4 and System Utilities 3.1.

It will not boot the MECC test disk either.

It makes the datalife test disk think that the disk drives are in slot 0 and will not recognize the drive I had in it.

However, it did work fine with ALL other disks I have tried.

I now think that the ROM chip on the card is so differently made that what I am dealing with is a compatibility problem.

Anyway, back to the iie. I will wait for Speedy's info tomorrow.

And yes, I have tried different slots. No dice.

EDIT: Found out how to load Copy II Plus 9.1 on the Laser UDC Card.

The disks I was making had something wrong with the Prodos Format or the Prodos file or both. I put Prodos 8 Version 2.0.3 and the Basic.Systen 1.5 file on a blank Prodos formatted disk, then simply copied the rest of the files from the Copy II Plus 9.1 disk onto the new disk, Sorted the catalog to match the original disk and then changed the volume name to match.

Copy II Plus 9.1 and Laser UDC loading problem fixed.

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Re: apple iie problem

Hello insanitor,

this posting will cover your first and your last posting.... so please first read the entire reply as well as the
listed links in this posting....
after that you can start with debugging and understand the dependencies and the
interaction of all of the components....

lets first start with the IIe mainboard:
the computer determines the action of the interface cards by the controllines IOSEL and DEVSEL lines.
This means, that if a card is to be selected to perform its duty it will be selected by this lines....
the 2 responsible chips are marked in the 2 pictures below - the first shows the location of that chips
and the second picture displays their connection in the circuitplan.
If you issue a commend like PR#xx ( where xx is the slotnumber ) that controllines will be activated
and the computer starts to read from the EPROMs or ROMs on that card and executes their commands....

If you start the computer the Firmware of the computer ( in fact the Autostart ROM F8 ) contains code
that the computer is forced to scan the slots and search for the controlbytes of a Disk or harddisk controller
and if he finds the controller he will issue a startcommand to that controller to read the operation system.
If one of the chips marked in the plan fails -
the computer will not be able to pass over the boot process to the controllercard in any of the slots

( which means that a controller will not work in any slot at all ! )

chip location plan ( relevant chips marked red ):

chips in circuitplan:

One very commen mistake that often occurs - is that a lot of poeple don´t remember
that there have been 2 kinds of Disk II controllers out there :
the one for 13 sector operation
and the one with 16 sector operation....
If you plug in a controller with PROMs for 13 sector operation and try to read a 16 sector disk
- that can´t work.
Its therefor important to know which kind of controller you are using !
You should check out the PROMs to find out
which kind of PROMs are on board and mark that controller somewhere visible with a label
to see if its for 13 sector- or 16 sector disks !
I´ve listed in the second picture at the right border side the correct PROM- numbers in red letters
and labelmarkings to find out which one is used.

In case that the 20-pin flatribbon cable has been plugged in wrong side around it may happen that the
2 transistors might have been damaged.... ( marked red in pictures )

the view to the DiskII controller:

the details by circuitplan:

In fact in most cases the controllers become damaged because the 20-pin flat ribbon cable had been plugged in the wrong direction to the controller.
This causes in general that the powerlines with the 12-Volt power get connected to the wrong traces
and damage the transistors or the chips connected to that traces
get damaged by wrong power running to them.

This often happens if the cables or plugs are not well marked, where pin 1 is
or if cable has been inserted wrong way around by earlier repairattempt -
you should check correct cableinsertion also inside of the drive. The connector has marking at pin 1 !
And it´s not bad idea to mark the cable outside of the drive at the end of the controller too !
Chips designed to operate at 5 Volt don´t survive an input of 12 Volt to the wrong pins....
the causes in general that nearly each time this mistake happens that the ULN2003 driver and the 74LS125
become destroyed. sometimes also the transistor in the upper right side gets damaged too...

here is the view to the Analog board of the DiskII ( which you will see if the top of the metalcase is taken off ):
the chips that become damaged in general are marked in red.

and here is the circuitplan:

More stuff on this topic has been published in the following pages....
there are infos on the dismounting and cleaning and maintenance of DISK II drives explained
with lots of pictures and further explenations and there you can also read all about calibration of the drives....

http://www.harrowalsh.de/Elektronik/APPLEBOX/appleboxdiskiipage1.htm
http://www.harrowalsh.de/Elektronik/APPLEBOX/appleboxdiskiipage2.htm
http://www.harrowalsh.de/Elektronik/APPLEBOX/appleboxdiskiipage3.htm
http://www.harrowalsh.de/Elektronik/APPLEBOX/appleboxdiskiipage4.htm

up to the moment i guess one drive to be damaged and one DISK II controller to be damaged or
of wrong kind with wrong PROMs ( you can´t use 13 sector controller for ProDOS disks! )

hope this gets you ahead to solve the problems when working along the post step by step....

sincerely speedyG

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Re: apple iie problem

Damn that was an awesome post speedy.

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Re: apple iie problem

I replaced the two chips indicated. No change.

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Re: apple iie problem

Hello insanitor,
it´s not only the 2 chips on mainboard......
it´s a checkout along the entire chain requested.....
and if the UDC is working the problem isn´t related to the 2 chips on the mainboard
( if it would have been one of the 2 chips the UDC would have failed also ),
but rather more to the other diskcontrollers and the used drives
( eliminating from the list of suspects those drives that work at the UDC ).......
so the correct checkout would continue with one drive that verfied to work and
sorting out the controllers that don´t work....
and later with a controller that is recognized to work sorting out the damaged drives...
this would at least be the conclusions from the text i posted....

and then finally attempting with the text that i have written to the damaged parts
and starting up with the repairs... step by step.....
sincerely speedyG

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Re: apple iie problem

Well, I have put on the motherboard a 5.25 drive and controller that are known to boot on an identical motherboard. They are fine. So it's not the adapter card or the drive. It's still the motherboard. The rest of the info you posted relates to the drive controller and the analog card on the disk drives. The disk drives boot on another motherboard. The drive controller works on another motherboard. This is why I asked for information on which chips on the motherboard control the power going to the drives. This is the problem with the motherboard, aside from the fact that the self-test lasts forever. At least if I could get an error message, I could troubleshoot a bit more, but without specialized equipment and training for me, it's not an option for me. Unfortunately, I am not an electronics technician. I fix things, usually using instinct and the process of elimination.

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Re: apple iie problem

Hello insanotor,
to answer that question:
th power ( + 5V, +12V, -12Volt and -5 Volt ) are passing from the powersupply unit directly to the slots,
without any kind of control.... they just pass along that path the coils nearby the powerin plug on the mainboard....
At the interface card they are also just passed through and only the Q2 and Q3 have influence to the
"motor on" command switching the motor ( spinning the disks ) on or off by the control of the 74LS05 on the interfacecard at location of B2.
On the DISK II analogboard the Stepping motor for the tracks is controlled by the ULN2003 which i mentioned to get damaged if the cable is attached wrong side around.....
the +12 Volt and +12V are passing the large coils on the analogboard and
handed over to the IC CX06SB on the smaller Motorsontrol PCB at the rear of the DISK II
close to the drivespeed trimmer and the transistors and diodes on the motorcontrol PCB.

The problem related to the "neverending" test indicate trouble with the RAM or the IOU chip.
IF the UDC and a drive is working on the malfunctioning system it might be good idea to try booting a testdisk instead of using the selftest and performing the tests from disk if possible...

sincerely speedyG

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Re: apple iie problem

Well, I am not using a Disk II analog card because I am using an a9m0107 disk drive.

The problem is that the power is for whatever reason not being fed to the controller card. So the disk drive does not spin up, nor does the LED on the disk drive come on.

The computer behaves as though there is no controller card attached to the computer at all.

And the self-test lasts forever.

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Re: apple iie problem

hello insanitor,
nice to hear now that you are not using the DISK II....
would have been usefull to issue that info earlier ???
I´ll be back tommorow after sleeping with further infos....
sincerely speedyG

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Re: apple iie problem

I DO have a disk ii drive and only one. I COULD hook it up to that computer but it would be a waste of time since there's nothing wrong with that drive or it's analog board as far as I can tell. I have modified the disk ii controller card and the drive to use DB-19 d-sub connector. How's THAT for preventing an improper connector placement!

I would prefer a more detailed schematic of the slots to see how to measure the power going to them. More like a schematic with the way the slots really look like.

I do not see how taking all these measurements on the analog board can help when the problem is not the analog board.

Or, I would like to know why the self-test lasts forever. The problem causing that might be related. You've provided no info concerning that. If I could see what the test results WOULD BE then maybe I have a chance of fixing it.

This particular motherboard has NEVER booted a 5.25 disk since I got it.

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Re: apple iie problem

Hello insanitor,

lets just take a view backward......

The innitial statemant had been:

insanitor wrote:

There's no power going to the disk drives on my bad iie motherboard.
The disk drive indicator light does not turn on and there's no spinning in the drive so it does not get any power from the motherboard.
I have checked the power supply and it has power going into the motherboard.
I have searched through several tech manuals but have no idea which chip controls the power going to the 5.25 disk controller.
Doing a pr#6 will hang the computer.
If I try a self test, the computer will self test forever, the only thing that changes is the amount of beeps.
The only thing I suppose I can do with it is use applesoft basic. When I turn on the motherboard, I get the apple //e and the command prompt.

the second statements added have been:

insanitor wrote:

I found out that the drive controller card really was dead when all this time I thought it was ok.
Still, when I put a known working card in there, it still won't work.

I decided to try something daring and put my Laser UDC card in it.
That did not work either and I found out a few things about my UDC card.
It will not boot Copy II Plus 9.1 but will work with 7.4 and System Utilities 3.1.
It will not boot the MECC test disk either.
It makes the datalife test disk think that the disk drives are in slot 0 and will not recognize the drive I had in it.
However, it did work fine with ALL other disks I have tried. (???)
Anyway, back to the iie. I will wait for Speedy's info tomorrow.
And yes, I have tried different slots. No dice.

this statements was UPDATED with:

EDIT: Found out how to load Copy II Plus 9.1 on the Laser UDC Card.
The disks I was making had something wrong with the Prodos Format or the Prodos file or both.
Copy II Plus 9.1 and Laser UDC loading problem fixed.

This second statement seemed to be a revision of the first statements by
claiming that the DISK II controller and at least one drive ( that was used ) to be failing
( if in general the discussion is about a unnamed drive it is assumed to be a DISK II drive
- unless specified to another kind of drive...).

- BUT the UDC to work and a drive availiable to boot !

=== We will see later that this updating information was completely missleading ! ===

At the moment this statement of a booting UDC leaded to the conclusion:
--> the F8 ROM isn´t faulty....
--> at least 48 kB RAM are not faulty....
--> the power to the UDC is correct and therefor the powerlines must be correct...
--> the mistake must be somewhere between the Disk II controller and the Disk II drive...

my first reply to the statements was:

speedyG wrote:

i posted the locationplan IIe
i posted the partial circuitplan related to the slots of the IIe

(resulting from the first part of the second posting: I have tried different slots. No dice. )

speedyG wrote:

i posted the picture of the DiskII controller for chip location
i posted the entire circuitplan of the Disk II controller
i posted the picture of the analog board of the Disk II
i posted the entire circuitplan of the Disk II

and i commented the functions and interaction of all of this components
and i explained that throughout that entire chain a fault might be possible

the answer to my reply was:

insanitor wrote:

I replaced the two chips indicated. No change.

my second reply was:

speedyG wrote:

it´s not only the 2 chips on mainboard......

reminding to my statement given in the first explaing posting....

speedyG wrote:

it´s a checkout along the entire chain requested.....
and if the UDC is working the problem isn´t related to the 2 chips on the mainboard (!!!)
( if it would have been one of the 2 chips the UDC would have failed also ),
but rather more to the other diskcontrollers and the used drives
( eliminating from the list of suspects those drives that work at the UDC ).......
so the correct checkout would continue with one drive that verfied to work and
sorting out the controllers that don´t work....
and later with a controller that is recognized to work sorting out the damaged drives...
this would at least be the conclusions from the text i posted....
and then finally attempting with the text that i have written to the damaged parts
and starting up with the repairs... step by step.....

the third statement was:

insanitor wrote:

Well, I have put on the motherboard a 5.25 drive and controller that are known to boot on an identical motherboard.
They are fine. So it's not the adapter card or the drive. It's still the motherboard.
The rest of the info you posted relates to the drive controller and the analog card on the disk drives.
The disk drives boot on another motherboard. The drive controller works on another motherboard.
This is why I asked for information on which chips on the motherboard control the power going to the drives.
This is the problem with the motherboard, aside from the fact that the self-test lasts forever.
At least if I could get an error message,
I could troubleshoot a bit more, but without specialized equipment and training for me, it's not an option for me.
I fix things, usually using instinct and the process of elimination.

remark to the (!!!) -> this third statement did NOT revise my statement about the UDC
---- NOR did it correct the wrong conclusion resulting from the earlier statements....

my second reply was related to the powerlines within the IIe and the Diskcontroller and the DISK II
as reply to the third statement:

speedyG wrote:

to answer that question:
the power ( + 5V, +12V, -12Volt and -5 Volt ) are passing from the powersupply unit directly to the slots,
without any kind of control.... they just pass along that path the coils nearby the powerin plug on the mainboard....
At the interface card they are also just passed through and only the Q2 and Q3 have influence to the
"motor on" command switching the motor ( spinning the disks ) on or off by the control of the 74LS05 on the interfacecard at location of B2.
On the DISK II analogboard the Stepping motor for the tracks is controlled by the ULN2003 which i mentioned to get damaged if the cable is attached wrong side around.....
the +12 Volt and +12V are passing the large coils on the analogboard and
handed over to the IC CX06SB on the smaller Motorsontrol PCB at the rear of the DISK II
close to the drivespeed trimmer and the transistors and diodes on the motorcontrol PCB.

The problem related to the "neverending" test indicate trouble with the RAM or the IOU chip.
IF the UDC and a drive is working on the malfunctioning system it might be good idea to try booting a testdisk instead of using the selftest and performing the tests from disk if possible.

the fourth statement was:

insanitor wrote:

Well, I am not using a Disk II analog card because I am using an a9m0107 disk drive.
The problem is that the power is for whatever reason not being fed to the controller card. comment: THIS IS WRONG
So the disk drive does not spin up, nor does the LED on the disk drive come on.
The computer behaves as though there is no controller card attached to the computer at all.
And the self-test lasts forever.

At this point i had to realize that i recieved a missleading information about a working UDC
causing to wrong conclusions by wrong input......
.
Before that information i had to conclude that:
It´s a very common known problem - that in computer determined for resurection
- before change of owner or short afterwards it happens that a DISK II drive is plugged in wrong side around
to the controller resulting to damages at drive and sometimes also to damaged controller
( in fact it´s nearly 75% of the faults related to DISK II problems.... )
--- therefor ---:
if the info about the a9m0107 drive would have been innitially passed over in the very first
posting -
i would have never wasted my time on guessing to this very common problem....
it would have changed the entire task and the conclusions too .....

that´s the reason i replied:

speedyG wrote:

nice to hear now that you are not using the DISK II....
would have been usefull to issue that info earlier ???

and as reply i recieved this fifth statement:

insanitor wrote:

I DO have a disk ii drive and only one.
I COULD hook it up to that computer but it would be a waste of time
since there's nothing wrong with that drive or it's analog board as far as I can tell.
I have modified the disk ii controller card and the drive to use DB-19 d-sub connector.
How's THAT for preventing an improper connector placement!

No comment except the explenation one paragraph above ....
except THAT it´s at least nice to see comments of wisdom on wrong conclusions resulting
from wrong inputing statements....

insanitor wrote:

I would prefer a more detailed schematic of the slots to see how to measure the power going to them.
More like a schematic with the way the slots really look like.

I´ll tell you why this is waste of time:
The powerlines go direct to the slots and to the RAM and several other chips
only passing through the coils close at the powerplug connector...
if you would have trouble with the power - the display would remain blank black or only display garbage !
You would have never seen the Apple IIe on display!

the only reason for the power not leading to the slots
would be a break of the wire within the coils
located at the powerplugsocket
and it would cause the above listed symptoms !

But if you startup and end at a prompt there are at least 4 conditions completed:

the power is availiable,
the datalines between CPU and RAM are O.K.
at least the first 16 kB of RAM are accessable.
this means that at least the adressinglines from A0 to A13 are O.K.
So at this point we must state that the trouble is dependent to the adressinglines of A14 and A15,
which are responsible for the adressingarea above 16 kB !
this would also match with the neverending selftest !

Neverthelass ... you requested that - and here you get it:

Here is the pinout of the Slots as availiable also in Internet:

Here is the detail view to the powerinput at the IIe Board from top view with comments:

Here is the detail view to the powerinput at the IIe Board from solderside view with comments:

insanitor wrote:

I do not see how taking all these measurements on the analog board can help when the problem is not the analog board.

Of course not... after adding the last information that became rediculous....

insanitor wrote:

Or, I would like to know why the self-test lasts forever. The problem causing that might be related.
You've provided no info concerning that.

Now with the new information we have to start again at that point i explained above about the A14 and A15 !

insanitor wrote:

If I could see what the test results WOULD BE then maybe I have a chance of fixing it.
This particular motherboard has NEVER booted a 5.25 disk since I got it.

With the information now availiable we could have started days ago at the point we are now.....

that´s why i now reply :

it´s getting better and better....

sincerely speedyG

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Re: apple iie problem

I am sorry if you got upset with my haphazard postings.

I am sure you understand now that teaching can be an even harder job than learning.

I know a lot of things and even I have come across the student that gave me A BAD DAY.

Still: I would like to point things out...

Your first pictures of the motherboards is for older ones. I have a platinum motherboard. You just assumed that I had the older model.

Concerning Disk II again, you assumed that I was using a disk II controller. I did not ever say that I was using one.

Making assumptions and then getting annoyed because the details were not explained to you is strange to me.

So now let me give you FULL information which it seems you need it.

1). I am using a PLATINUM motherboard for the iie. The one which has a different colored plastic on it and has a numeric keypad. Model number a2s2128.

2). This means that my computer is ENHANCED.

3). That also means that if the motherboard has a different design, you might want to provide a schematic for the design of MY motherboard and NOT for another one.

4). I am using an a9m0107 disk drive which is known to work on another PLATINUM iie.

5). The disk controller card I am using is a model number 655-0101-D. The rom chips indicate, (according to your information) a 16 sector disk controller and NOT a 13 sector one. It is NOT a disk ii controller card. I was NEVER testing this motherboard with a disk ii controller but you assumed I was.

6). I might have no choice but to return this to it's previous owner if that is possible.

Now for some new information which you probably already know.

I have measured all the voltages and they are all fine. Both at the slots and the coils.

That's all fine and dandy however...

You did not tell me what this statement means:

speedyG wrote:

So at this point we must state that the trouble is dependent to the adressinglines of A14 and A15,
which are responsible for the adressingarea above 16 kB !
this would also match with the neverending selftest !

What does one do about this problem...? Take voltages at the slots which in your schematic say are a14 and a15? And if there are supposed to be voltages there, what are they supposed to be? Or, do you mean that I should CHECK FOR CONTINUITY for all connections going directly to A14 and A15?

Concerning the self test, you said:

speedyG wrote:

The problem related to the "neverending" test indicate trouble with the RAM or the IOU chip.

So if I replace the RAM and the IOU chip, will this fix the problem or, is the fact that we're dealing with a platinum motherboard throw things off a bit...?

Sorry if it seems that I mislead you, but I would like you to know that while you have been helping me here, I have been doing all sorts of things on a lot of other apple ii stuff and the information I have on this changes because I get new information.

But I think concerning the IOU chip, you are correct. The corrosion I saw is around the location of the IOU chip. And also at a what I believe to be a capacitor right below it.

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Re: apple iie problem

Hello insanitor,

i was not upset... otherwise i just would have cancelled the communication with short brief message...
i just wanted to explain how this happened and show how important complete information is....
i´m in the situation that i can´t measure your board...
so i´m reliable to accurate information, because only accurate information leads to accurate results....

the other problem is that we are located quite apart on the globe... causing delays in the replies...
anyhow you just got me again just before heading for my portion of sleep....
so i´ll reply tommorow ....
but for the short shot.... the adressing lines A14 and A15 are dynamically working lines
( you can´t attempt them with a DMM. They can only be diagnosed by symptoms or measured with oscilloscope...)
but if you take a good picture of the area around the IOU chip with the chip inside of the socket
and once removed out of the socket it would be very usefull for diagnostic....
just place here a link to the pictures and it will help me ahead...

tommorow i´ll think over, where we are now and i´ll reply after i´ve got my morning coffee in my belly....
maybe the pictures are allready availiable....
best would be resolution of 300 dpi and resolution close to 3600 x 2400
this permits me to zoom in to details...
important is good light and good focus...

sincerely speedyG

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Re: apple iie problem

HOUSTON, WE HAVE A PROBLEM!!!!!!!!!!

Pics are unbelievable!

ftp://anonymous:thte@209.150.39.13/sda_part1/IOUCHIP.jpg

ftp://anonymous:thte@209.150.39.13/sda_part1/IOUCHIPREMOVED.jpg

ftp://anonymous:thte@209.150.39.13/sda_part1/IOUCHIPREMOVED2.jpg

It MUST have something to do with the IOU chip. You were right.

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Re: apple iie problem

Hello insanitor,
this looks very much like the unprofessional earlier attempt to change the IOU chip,
by trying to lift up the chip with a screwdriver instead of using the vacuumpump and
desoldeing wick. It will get rather difficult to rescue such a repair.
Another picture is required from the soldering side of that area in same quality ( the
pictures are excellent !!! ), it should show the entire area on the soldering side of the
IOU chip and the borderarea about 2 inches around the chip to see also where the broken
traces lead too
. Maybe i can make proposals how to rescue the board......

for a professional repair you would need:

at least you should try to aquire in the meantime a 40-pin precesionsocket
some half yard of very thin enameled copper wire with diameter of 0,15 mm or better 0,2 mm
( maybe you have an old damaged transformer from where you may wrap off such wire )
a desoldering vacuumpump and desoldeing wick 1,5 mm or 2mm width
and a very good solderingstation with a solderingiron and regulated temperature from
250 degrees to 450 degrees Celsius
and very fine penciltip with classification of
regulation between 15 Watt and 45 Watt. The soldering tip of the soldering iron should be
"potentalfree" meaning that the tip is isolated from the electrical regulation of the station.
which would be demanded for a repair.

sincerely speedyG

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In early days I had a lot of money but no time - now I have no money but a lot of time....
the second part includes less friends but a lot more joy on life....

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Posts: 792
Re: apple iie problem

I cleaned it all and flattened the extra solder.

But unfortunately, I do not have the equipment you described to do a "Professional Repair".

The only thing I have is the 40-pin socket.

So I am ready to solder it in and to put another chip on there.

ftp://anonymous:thte@209.150.39.13/sda_part1/top.jpg

ftp://anonymous:thte@209.150.39.13/sda_part1/bottom.jpg

EDIT:

I have finished testing most of the traces that I could see. Those came out fine.

speedyG's picture
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Joined: Nov 16 2011
Posts: 2376
Re: apple iie problem

Hello insanitor,
i started allready with making the instructions. If the traces measure to be O.K.you might drop the related single steps.
i will now revise the last picture taken from componentside and the one from the solderingside and then continue with that instructions still needed.
Up till now you may pick up the pictures made:
http://www.harrowalsh.de/Upload/IOUCHIPREMOVEDA.jpg
http://www.harrowalsh.de/Upload/IOUCHIPREMOVEDsinglestep01.jpg
http://www.harrowalsh.de/Upload/IOUCHIPREMOVEDsinglestep02.jpg
http://www.harrowalsh.de/Upload/IOUCHIPREMOVEDsinglestep03.jpg
http://www.harrowalsh.de/Upload/IOUCHIPREMOVEDsinglestep03.jpg

sincerely speedyG

UPDATE:

Checkout marked areas in both pictures...

http://www.harrowalsh.de/Upload/IOUCHIPREMOVEDTOP00.jpg
http://www.harrowalsh.de/Upload/IOUCHIPSOLDERSIDE00.jpg

the area looks quite well now after cleaning !

if points are checked you could insert socket and solder it in.....
checkout again connections and hunt for shortcuts...

and then you might try another IOU chip in the socket - but keep care its inserted with correct orientation
- its very common to make mistake, when in hurry.....
please give feedback if task was successful or not ...
if not we´ll continue checking the board....
good luck...
sincerely speedyG

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In early days I had a lot of money but no time - now I have no money but a lot of time....
the second part includes less friends but a lot more joy on life....

Online
Joined: May 27 2013
Posts: 792
Re: apple iie problem

Well, Speedy. You can stop giving advice now.

I cannot fix this.

After I cleaned the area I checked all the traces for continuity. All checked out, no shorts, nothing.

When I installed the new chip I got the exact same symptoms but now I can't even run the self-test at all.

The more I mess with it the worse it gets.

This piece of junk is going back to the person who gave it to me and that's that.

Ende.