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Apple ][ Plus Woes


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I just got an Apple ][ Plus, but the monitor doesn't work - I need to hold the v-sync dial further than it actually goes in order to see a picture (Comrex video monitor).  So I connected it to a projector and got it to show Apple ][, but nothing else.  I also couldn't get the disk drive to work - it just showed that it was in use and nothing else.  And then the computer died on me, and it no longer shows a picture with the projector (but it does beep and show a light - the projector just shows a no source found message).

 

Having no experience whatsoever with these machines, I don't know what to do.  Tips?  Why would the computer be working one minute and then dead another?  Is the monitor dial just broken and there's nothing I can do about it?  I read somewhere that orienting the disk drive connector wrong can break it - what is the right way to orient it (I'm worrying that I broke it already)?  And how would I boot into BASIC once I get it working again?  Thank you for bothering to answer what are probably obvious questions!

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  • 2 weeks later...
  • 5 months later...

I have soldered the joint and it now appears to be solid (the joint no longer twists), but the computer still doesn't output a signal.  Any other tips?  I'm rather confused because it was working for the first day or so in my possession, so it seems natural to me that the video jack would have failed after I plugged it in a few times.

 

I actually learned to solder specifically for this and I may have messed up, so attached is a photo of the connection - please excuse the dust!

 

IMG_9054.thumb.JPG.0ad11493f40edb268aded3fab563985e.JPG!

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  • 3 months later...

Sorry about the late response here!  I took a break from working on it.  The pin appeared to be fine, though, and there was continuity between the extra breakout video header and the pin as well.

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Apple II+ / IIe / Stealth IIgs Power Connector

Power Supply Connector Socket      Power Supply Output Ratings
              _________
             /         \            +5V @ 2.50 Amps (continuous)
   -12V GRN  |  5   6  | BLU -5V    -5V @ 0.25 Amps (continuous)
             |         |           +12V @ 1.50 Amps (continuous)
    +5V ORN  |  3   4  | YEL +12V  -12V @ 0.25 Amps (continuous)
             |         |
    GND BLK  |  1   2  | BLK GND
             |_________|

Make sure you measure the power going into the computer. If it had bad power, you're just going to blow out more stuff on the computer if you keep running it on that PSU.

 

You can also buy new PSU boards from here: https://www.reactivemicro.com/product/universal-psu-kit/#prettyPhoto[product-gallery]/0/

 

Or BE CARFUL and take out these three chips then put then back-in (aka re-seat them). Can't remember which one but if one of them doesn't have a good connection your computer screen will be black.

NOTE: take a close picture of the chips before you take them out so your don't forget what direction or order they go in etc.

image.png.f0c3e8b0228261f0a3c999da40db5f5f.png

 

When you take out the motherboard from the case some of the screws go into plastic risers. You will have to clamp them when you try to unscrew them.

image.png.ebbe79b914954b2e40cd8101abe778ea.png

Edited by zezba9000
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Reseating A8 seemed to temporarily fix it.  I could see a green line on the monitor, which is what I saw when the computer worked.  When I grabbed my projector though (which is the only other display device I have for seeing composite video), it no longer worked on either monitor.  I bent the pins pulling out the chip and had to bend them back into shape, so I'm not super keen on pulling it out again (if you have any tips for that, let me know).  It's heartening that it "worked" at least temporarily though.

 

Interestingly, I noticed that before I reseated A8, the computer beeped twice upon start up, and afterwards only once (I didn't have the keyboard connected for either).  I'm going to play around with it a bit more and see if I can get the picture back.

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It works!  I think it's a video port problem now, as it's intermittent and jostling the video cable can fix it.  I'll take a look at my solder joint again and maybe reflow it.

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Perhaps I spoke a bit too soon.  I think several things are going on.

 

The video is intermittent - that's a port issue.

Not all keys on the keyboard work.  I'm going to open it up and make sure all the keys are making good connections.

And the most puzzling - intermittent operation.  Sometimes CTRL-Reset works, sometimes it doesn't (but it always beeps).  Sometimes, pressing it just puts characters in random places on the screen, and when I click it again the character seems to increment (if it started as a 0: 0 --> 1 --> 2 etc.).  Twice, it's dropped me straight into the monitor (where I've been able to test the keys), but it's never brought me to the BASIC prompt (I may be remembering that it's supposed to do that incorrectly though).  I don't know where to start with this, so any ideas for what could be causing it?

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On 10/12/2020 at 1:13 AM, RC14 said:

Reseating A8 seemed to temporarily fix it.  I could see a green line on the monitor, which is what I saw when the computer worked.  When I grabbed my projector though (which is the only other display device I have for seeing composite video), it no longer worked on either monitor.  I bent the pins pulling out the chip and had to bend them back into shape, so I'm not super keen on pulling it out again (if you have any tips for that, let me know).  It's heartening that it "worked" at least temporarily though.

 

Interestingly, I noticed that before I reseated A8, the computer beeped twice upon start up, and afterwards only once (I didn't have the keyboard connected for either).  I'm going to play around with it a bit more and see if I can get the picture back.

------------------

You must have the keyboard connected for the computer to work (don't turn it on without keyboard plugged in). Just unscrew the keyboard and take it out of the frame.

When you pull out the chip (and don't have good tools for it) just use a flat-head and very SLOWLLY rotate the flat-head at the base of the chip so it pushes up on each side of the chip until you can pull it out without bending pins.

 

------------------

Pull the A8 chip out again and clean the prongs with "isopropyl alcohol" and cue-tips.  You probably have other chips not making good connection or a bad keyboard cable or keyboard connection (clean that connection as well).

 

------------------

Next step is to get a voltmeter and set it to measure resistance. Test each wire on the keyboard cable to make sure it has zero resistance. That way you can see if there are bad wires/leads.

You also need a voltmeter to test the PSU (have you done that yet?).

 

------------------

If you're getting desperate, put the motherboard in the dishwasher (and use those nice hybrid soap blocks/cubes from "Cascade brand"), let it heat dry and then use an air blower / shop-vac to make sure its totally dry. Then poor "isopropyl alcohol" on it to further to help dry out things and blow it out again with a shop vac.

Make sure its 100% dry before you turn it on again and make sure you start drying it as soon as its out of the dishwasher.

 

------------------

If you still have issues reset all chip. Make sure you have a method that doesn't bend pins. It will take awhile but reseating them all might work.

Edited by zezba9000
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