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Thread: Apple //e Clone (Orange ? )

  1. #1
    Join Date
    Aug 2019
    Location
    Prince Edward Island
    Posts
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    Question Apple //e Clone (Orange ? )

    Looking for diagnostic suggestions.

    I have an North American Apple //e Clone that some people think is an Orange (based on the keyboard)
    There is nothing identifying the model except for the "apple" keys.


    A year ago I upgraded it to be an enhanced //e and it ran fine.

    Symptoms:
    A couple of months ago, I started it up and I just get a no-signal screen on power up.
    LED for power turns on, on the motherboard and on the keyboard.
    No power-on beep.
    No message on screen.
    No spin from disks.
    Voltages are ok from Power Supply.

    What I've tried so far
    I tried diagnosing the problem via this guide: http://apple2online.com/web_document...pair_guide.pdf
    Based on section Part 1 steps 1-3, I bought from DigiKey (not China) and replaced E3 (74LS125) and E4 (74LS02), but no change.
    I had bought a 74LS109 but... there isn't one on the motherboard <ha ha> Closest is 74LS10 -- I'll need to look up the data sheet.

    Any suggestions greatly appreciated.




  2. #2

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    Hello, you didn't mention if you had any testing equipment (scope, meter or logic probe) but if you do, I would first check the power inputs with a meter to match those printed on the board. If you have a scope, you can start tracking signals back from the 6502 to see which chip has gone bad. It would help to have a schematic but your clone board is not an exact Apple copy so I don't know if an Apple II/e schematic would work. After you verify power, check for a clock signal on the 6502; then see if there is activity on the data and address lines of the 6502. You can also check for activity on the 2764 EPROM and the the 2114 RAM.

    If you don't have a scope, use/buy a cheap logic probe and you can use this to track down logic signals on the board. If I had to make a wild guess, I would at least suspect the 2114 RAM or bus drivers. After that, your 2764 EPROM could have failed. That chip should be backed up if it is working and the window covered with black tape.

    Even without a schematic, online data sheets can show you what logic should be on the individual chips in the machine. As an absolute last resort, you could try switching out chips with known good chips but that gets expensive. The 2114 memory is about $2.50 US each from places like Jameco.

    Good luck.
    > Charles

    EDIT: 4164 RAM = $2.25 US
    Last edited by Dawsoca; January 10th, 2020 at 03:39 PM. Reason: Wrong RAM

  3. #3
    Join Date
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    libtard capital, California
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    Default

    those are Korean IIe clones (I have a couple) They're functionally identical to IIe, but none of the ASICs are compatible with anything in IIe.

  4. #4

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    Quote Originally Posted by dorkbert View Post
    those are Korean IIe clones (I have a couple) They're functionally identical to IIe, but none of the ASICs are compatible with anything in IIe.
    The ASICs are 100% clones of a2e MMU and IOU. Unlike the topic starter I see 74LS109 in the lower left corner of the motherboard. I see an upgraded enhanced kit which uses with very high probability a Chinese fake of 65C02P4 (could be a mere lower frequency 6502). Place back the original non-enhanced chips first.

  5. #5
    Join Date
    Sep 2016
    Location
    Melbourne, Australia
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    635

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    Quote Originally Posted by dorkbert View Post
    those are Korean IIe clones (I have a couple) They're functionally identical to IIe, but none of the ASICs are compatible with anything in IIe.
    Mostly correct, all the 2e clones from multiple countries not just korea used that same chipset.
    Yes, while they are functional identical to the asics in a 2e, they are not pin compatible.

  6. #6

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    Using that trouble shooting chart with a clone is likely to not help much.
    A 74LS109 and a 74LS10 are about as different as a motorcycle and a Mack truck.
    Trouble shooting is a sequence of looking to see what it stops doing the right thing at.
    You need to check the voltages, clocks and reset signal first. Things get more complicated after that but these are the first things.
    Even without a schematic, there are some things that can be done.
    I don't usually recommend Easter egg hunting as a trouble shooting method. Still to do much more does require some tools.
    What trouble shooting tools do you have?
    Dwight

  7. Default

    That looks like the spit image of my CloneE. Of course mine is in Australia though. I'll try and get a decent photo of the motherboard for comparison, if you want readings off anything for comparison yell, but I only have a multi-meter.. Mine was also "un-enahnced" as I received it, however I only put a 65c02 in it, and it's behaved for all intents and purposes perfectly as an enhanced IIe.
    -------------------------------------------------------------------------------------------
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  8. #8

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    Quote Originally Posted by David_M View Post
    Mostly correct, all the 2e clones from multiple countries not just korea used that same chipset.
    Yes, while they are functional identical to the asics in a 2e, they are not pin compatible.
    Well, you speak with such certainty but remembering the same foolish certainty when you opposed to me about your poor Saturn card's design I definitely doubt in what you say now. For example Bulgarian //e clones (Pravetz 8A/8C/8S) have 100% pin compatible MMU and IOU (CM631/CM632) and I have even repaired with Bulgarian MMU my prototyping Apple //e that is experiencing a lot of experiments with peripheral cards...And vice versa -- I have used many times in Bulgarian clones the original Apple's MMU and IOUs...I am 99% sure that the Asian MMU/IOU clones are also pin compatible with the Apple's //e MMU and IOUs. Many chips back then were cloned "blindly" and internally have the same schematics.
    Last edited by george; January 16th, 2020 at 02:09 PM.

  9. #9

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    Quote Originally Posted by David_M View Post
    Mostly correct, all the 2e clones from multiple countries not just korea used that same chipset.
    Yes, while they are functional identical to the asics in a 2e, they are not pin compatible.
    Well, you speak with such certainty but remembering the same foolish certainty when you opposed to me about your poor Saturn card's design I definitely doubt in what you say now. For example Bulgarian //e clones (Pravetz 8A/8C/8S) have 100% pin compatible MMU and IOU (CM631/CM632) and I have even repaired with Bulgarian MMU my prototyping Apple //e that is suffering a lot of experiments with peripheral cards...I am 99% sure the Asian MMU/IOU clones are also pin compatible with the Apple 2e's MMU and IOUs. Many chips back then were cloned "blindly" thus having internally the same schematics which is externally wired to the same pins, of course.

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