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  • #91
    Originally posted by nauseous View Post
    Howdy Apple gurus. I have a few Apples that I am repairing. My question is, without a working disk drive and no rs232 (Apple II+) what would be the easiest way to load diagnostic test disks?

    Cheers!
    For the IIe's (4xPlatinum + 2 regular) I'd recommend the built in self test (assuming the RAM is in reasonable condition.it will run) - Key sequence is Control, Open Apple, Reset. It will test the RAM and some of the key custom IC's.

    The 2 Europlus are a little more tricky due to the number of chips - I'd start with reseating all the IC's and then removing everything but the 1st bank of RAM.

    Obviously before starting these computers up make sure you take care of the RIFA caps in the power supply.

    As you have discovered you will likely struggle to load software directly into memory if there are any faults with the computer. You can however try places like this https://asciiexpress.net/diskserver/ which have a range of software setup for audio delivery. I didn't see any test software. Obviously ADTPro with a disk drive is your best option.

    Cheers

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    • #92
      Thanks D.C - So far I have had a pretty good run with the machines but I suspect now some of the Custom IC's in the 2e's are at fault. I don't like my chances of finding replacement IOU/MMU IC's. In all I have got 5 out of 8 machines booting up to display Apple ][. Lots more work to go yet troubleshooting. The Europlus is on hold waiting 74LS153 order, but the II Plus is working again. Like you said I got it to boot with just the first 16kb of RAM, then started adding banks back one at a time, including the language card. And I also replaced all filter capacitors in all 8 power supplies - these appear to be testing good now.

      I grabbed out 2 floppy drives (Apple Disk II) and 2 disk controllers to try with ADTPro, along with the Super Serial II card. I am having issues with my windows 10 laptop not detecting the COM port in ADTPro - so I haven't been able to bootstrap via serial connection. And both drives fail to read/write to a disk but both controllers appear to work. So at the moment I am a bit stuck, I am hoping the calibration guides online might help get one drive to a working status again.

      And thanks Jedi/Arcade King for the offer. Arcade if you don't mind I might just take you up on the offer of a loaner.


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      • #93
        OK So a bit more progress. ADTPro requires 64bit Java, with this fixed I have been able to send data via the Super Serial II Card and load DOS. This makes testing easier, via serial I can push data at 115200 baud.

        So onto repairing drives, I have found a few good pages regarding DISK II repairs, but for now I am going to follow "Sams - Computerfacts" repair book.
        https://mirrors.apple2.org.za/Apple%...Apple%20II.pdf

        This page also looks like it might have some good tips.
        http://www.apple2faq.com/knowledgeba...g-disk-drives/

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        • #94
          Originally posted by nauseous View Post
          Thanks D.C - So far I have had a pretty good run with the machines but I suspect now some of the Custom IC's in the 2e's are at fault. I don't like my chances of finding replacement IOU/MMU IC's. In all I have got 5 out of 8 machines booting up to display Apple ][. Lots more work to go yet troubleshooting. The Europlus is on hold waiting 74LS153 order, but the II Plus is working again. Like you said I got it to boot with just the first 16kb of RAM, then started adding banks back one at a time, including the language card. And I also replaced all filter capacitors in all 8 power supplies - these appear to be testing good now.

          I grabbed out 2 floppy drives (Apple Disk II) and 2 disk controllers to try with ADTPro, along with the Super Serial II card. I am having issues with my windows 10 laptop not detecting the COM port in ADTPro - so I haven't been able to bootstrap via serial connection. And both drives fail to read/write to a disk but both controllers appear to work. So at the moment I am a bit stuck, I am hoping the calibration guides online might help get one drive to a working status again.

          And thanks Jedi/Arcade King for the offer. Arcade if you don't mind I might just take you up on the offer of a loaner.
          Sounds like good progress. Other than the earlier Apple II's the later models I've found to be very reliable, RAM/ROMS tends to be the biggest issues. What makes you suspect the customs IC's? Out of about 50+ 2c/2e I've worked on I've only ever had 1 IOU failure and I was able to get a replacement.

          Regarding the disk drives can you describe what the drive is doing when you try to read/write a disk (or format if your using ADTPro). Have you done basic maintenance like cleaning the drive head? Also ensure your floppy disk are the correct type (ie. no high density)..

          With ADTPro I use an old machine with a serial port but I've had success with a usb/serial adaptor on newer machines. Is ADTPro giving you a message to make you believe it's not detecting the COM port? Depending on the type of cable your using (null modem or straight) you need to change the jumper block on the super serial card.

          I'm in Melbourne but happy to help sort out your drives if you want to PM me.

          Cheers

          Comment


          • #95
            Well that is encouraging what you say regarding the custom IC's. In the 4 boards I have the IOU ic's are all soldered in, I have removed the 2 that I suspect might be at fault and am now just waiting on some 40pin sockets to arrive (all out..) Once they arrive I can start swapping chips around into known working board to see what I get.

            One of those IOU's failed to give the reset signal from pin 15 to the 6502 CPU whilst in board. The reset line appears to be dead coming from that IOU chip. The other failed to give graphic output / video timing - I'm hoping this isn't IOU related. Will update when I know a bit more.

            Still having no luck with the Floppy Drives and reading media. Basic maintenance has been performed, as well as adjusting motor speed to be roughly 60hz.
            Drive 1 (Disk II): Dead MC3470AP - Doesn't appear in Volumes list under ADTPro.
            Drive 2 (Disk II): Everything appears to check out OK on Oscillopscope, . Cant Read Disk (I/O Error), Can't Write Disk (Disk faulty or Check Drive Door) using ADTPro.
            Drive 3 (Rana Systems - Elite One): Doesn't appear in Volumes list under ADTPro. (Yet to be troubleshooted)

            I have a few more drives I can test with yet... If I could just get one to work then I might have a path to get the others working.








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            • #96
              Yes if you can get at least one working system it's makes diagnosing other issues so much easier.

              I'll send you a pm

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              • #97
                I managed to track down a cheap SD II Interface board that should be arriving this week. That will finally let me get to the bottom of this floppy situation.

                In the meantime I have managed to get 7 out of the 8 machines returned to operation. Confirmed only 1 dead MMU and 1 dead IOU chip, plus a bunch of failed cpu, rom and ram ICs that had to be replaced. Just in the final stages of re-assembling the last 2 machines now.

                Not a bad outcome. Clones are still pending parts from China for the power supplies before I can start troubleshooting them (not a standard apple power plug on m/b).

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                • #98
                  https://www.ebay.com.au/itm/Dual-Dri...gAAOSwWnhebmb-

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                  • #99
                    Oh my.

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                    • It's how bad the conversion rate is that's got me



                      2,445.98 bucks!

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                      • Another update from my end. SDisk II interface arrived, I assembled it and it works as expected. This has allowed me to load troubleshooting tools and get 2 floppy drives working. Mixture of bad IC's, bad floppies and repeated dirty heads. I'm moving onto a lot of 5 or 6 Apple IIG's next, this time I will make a better effort to document the fixes. Good news so far is no battery damage on any of the motherboards.

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                        • Originally posted by Arcade King View Post
                          It's how bad the conversion rate is that's got me



                          2,445.98 bucks!
                          Forget ordering anything from overseas for a very, very long time. That's even if the country the seller is in has postal services that'll even let them send stuff to you!

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                            • Picked up this Apple 2 "experimenter's" kit, not sure if I will ever get to it, but would like to one day.
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