Looking for Apple IIe PAL schematics / not starting

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Looking for Apple IIe PAL schematics / not starting

I'm looking for an Apple IIe PAL version schematic..
or a pdf copy of understanding the apple IIe (as I believe it has a schematic of the PAL version)

My Apple IIe has the following problem: No power light, no beep, drive won't run
It's not the power supply..
A repair manual for NTSC IIe suggests:
---------------
Probable defect:
1) 74LS125 at E1 is bad (replace and test)
2) 74S109 at C1 is bad (replace and test)
3) 74S02 at B8 is bad (replace and test)
---------------
But the Apple IIe PAL version has a different set of components/board layout...

thanks in advance! been breaking my head over it for a few weeks now...

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PAL

3) Power light on, message, no beep:
Probable defect: 1) (experts only) PAL 16R8/8323T at D1 is bad

http://vintagecomputermanuals.com/Apple/PDF%20Apple%20%20Articles/Apple%20IIe%20Repair%20Guide.htm

manuals Apple IIe - Apple IIe Technical Reference Manual
http://www.apple-iigs.info/doc/docii.htm
and
http://www.1000bit.net/scheda.asp?id=1
.
.

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Re: PAL

no, power light doesnt work .. "No power light, no beep, drive won't run" i said
1) 74LS125 at E1 is bad (replace and test)
2) 74S109 at C1 is bad (replace and test)
3) 74S02 at B8 is bad (replace and test)
That repair guide is for US version, the schematics and component layout is totally different on the PAL version...

the only publication i know that should have the correct info is "Understanding The Apple IIe", unlike "Understanding The Apple II" it isn't widely available..
I read some posts somewhere on a site that had it available that the original author/publisher requested to pull it off..

Thanks for trying to help though!

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Understanding the Apple IIe
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wow a whopping 130MB! than

wow a whopping 130MB!

thanks a lot though! google didn't help me....

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tech savvy people are still w

tech savvy people are still welcome to give suggestions though

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google didn't help me....
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Re: google didn't help me....

hmm yes, the last of 9 google results leads me there..

strange, didn't spot this earlier (one month ago I spent a significant amount of time looking for it)

I see the dutch google.be link, nice to see fellow Belgians here Smile

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UPDATE: -------- I repl

UPDATE:
--------

I replaced all 3 recommend ic's (LS125,S109, S02).

Still not working..

However, now the power led flashes in a weird random pattern (it didn't give any light at all before I replaced it), while a nasty hi pitched tone (that comes from the power supply I think) seems to follow that same pattern...
I repeat though, I tested the PSU with another Apple IIe and It works 100% fine.

What can it be? Anyone?

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i just found this in "Underst

i just found this in "Understanding the Apple IIe"

"The Apple is dead and there is a low level clickin noise coming from the power supply.
If there is a clicking noise, the power supply is quite likely good, but a motherboard, peripheral card, or auxiliary card malfunction is causing an overload condition.
The clicking noise is the tinkerer's symptom." ... etc

They go on but nothing really helpful.. I haven't been tinkering with that computer, It has been in an attick for over a decade..
I'll try feeling if a chip gets hot or something.

EDIT:
UPDATE2:
-------
I also swapped/replaced the IOU chip and the PAL HAL.
No luck..
But one thing was strange, when I put the PAL HAL from the broken IIe in a working Apple , it's doesn't boot/beep anymore.
But placing a perfectly working PAL HAL in the broken one didn't change a thing at all..

I'm really out of ideas here.
When they say the timing HAL, do they mean the PAL HAL?

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I'd suggest that you remove t

I'd suggest that you remove the disk controller card from your Apple II as a first step, since it could be the culprit.

If the Apple is still not working, check all power supplied to the board while PSU still connected to board. Since the high-pitched noise suggests a short-circuit somewhere on the board, try removing one IC at a time (while Apple switched OFF of course!) and see if you can eliminate that condition.

Try hooking up a monitor and see what it shows. Is it black? Is it a random character pattern? Is it a fixed character pattern? Swap around the RAM IC's systematically and see if there is any change in the behavior. Remember that there can be several non-functional IC's on a non-working Apple (mine had one broken RAM IC and one broken bus driver IC).

Next step is perhaps to check the function of bus drivers. These would be my first target, since they are easily broken if a peripheral card is inserted or removed while the Apple by mistake is still powered. Remove the IC's and test manually using e.g. a prototyping board.

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Re: Looking for Apple IIe PAL schematics / not starting

Hi there,

at our computer museum we had some Apple IIe with the same defect:

capacitors at C12 were short dead!

Just check them, they're quite old and can be easily replaced. With a short, the power supply start clicking because goes into protection. C12 is for +5V.

Also check other similar capacitors (C17,C15,C9, etc)

Hope this can help Wink

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