Apple II+

I got an Apple II+ from an estate sale and am working to get it running.

Internals 

The internals looked all clean from initial inspection.  However, of the four peripheral cards inside, one was clearly broken, with part of it left laid down on the motherboard.

The broken card was an Epson printer board.  Part of it was still in one of the expansion port slots.  I was able to grab the "teeth" part by hand, and gently wiggle it out of the port slot.  With some careful positioning, I was able to put the parts back together using CA glue, though obviously that wouldn't fix it electronically.

A second board inside is a Video 7 card.  It had a few connection pins hanging off of it, and eventually went to something like a VGA port.  I couldn't find any documentation on it, so I've removed it.

A third board was a RAM expansion, typical of the day, taking me up from 48kB to 64 kB memory.  I kept that one plugged in.

The fourth board is an Apple Disk II board.  There were two legacy 5.25" floppy drives attached.  After some experimentation, I found that Drive 1 was working, but Drive 2 wasn't reliable.

Before turning on the system, I had to inspect and repair a few things.

First, I was hearing a rattling sound inside the main case.  I could already see that there was a paper clip magnetized to the speaker.  Overall, I was afraid something else down there might short out the board.  

I figured out how to fully open the case and get things apart.  That started with removing the obvious case screws on the bottom.  Then, I had to carefully loosen screws at the back of the motherboard that were holding on to a thin, metal "clip", which I am guessing was either a grounding or shielding mechanism.

After undoing the normal set of items within (PSU, keyboard,  speaker), I was able to get the case top off of the case bottom.

Removing the motherboard for inspection meant that I had to undo the plastic clip posts in the middle of the board.  I broke one of them.  They can be ordered online for an enormous shipping price, so I've left it as is.

Finally, after getting the motherboard off, I found an old 1980s quarter, a 1980s nickel, and another metal paperclip.

I also found a little, white plastic clip.  It turns out that that was part of the spacebar assembly.

Otherwise, the computer looked to be in really good, clean condition.  Only a small wipe-down was needed to clear out old dust.  This kind of computer does not have an internal battery, so there wasn't any chance of having that explode within.  And, none of the capacitors appeared to have failed.

I also took apart the PSU and inspected it, and it looked good.  However, I noticed that the PSU had a 110 vs 220 slider switch on the back, and it was in a 220 position when I got it.  I slid it back over to 110 for my purposes.

After doing the reassembly, I found an old TV with Composite In, hooked up the Video Out, and turned it on.  A Ctrl+Reset put me into Applesoft ("]" prompt) and I could type GR and then TEXT, and see a page of mostly "@" signs.

I tried various TVs of days gone by.  Most of them worked.  Some required an RF converter.  Only one TV didn't work -- an old security monitor CRT.  I won't to bother to fix that one.

The keyboard 

The next order of business was fixing the keyboard.  Upon receipt, the "-=" key was broken off its post, and the spacebar was janky.

For the "-=" key, I reopened the whole case, and de-soldered the ALPS switch within.  That allowed me a clean way to put the original key stem and the key switch into a vise, and get it glued together with CA glue.

For the spacebar, there wasn't much documentation on how to fix it.  In the end, I took the white post that I'd found within the case, and pushed it into the space key's left side keycap holder.  Then, I carefully pivoted the metal stabilizer bar (which was in its original position) such that the tips at each end went into the upper hole in the fin posts.  Then, after adding a spring to the middle keycap area, I pushed the spacebar back into place.  It's holding so far.

Finally, I added a spring to the RESET key at the top, right of the board, just to combat accidental keypresses.

I did a small amount of Q-tip cleaning of the board, and then put all the keycaps back where they started from, and all seemed to work.  There are occasionally double keypresses showing, suggesting incomplete debouncing in the software, but overall it works well.

 Video

 I tried various video options.  There is a composite Video Out jack on the back of the box.  I tried these configurations:

1. Video Out -> RF modulator -> TV In, channel 3 or 4.  Worked on Samsung UN50J5200AFXZA large TV.  3-prong power cable, typical 44W.

2. Same as above, worked on Magnavox 20MF200V/17.  12V, 5A max (60W).

3. Same as above to Spectra 58-MBWR.  Failed.  Bad, old TV CRT.

4. Video Out -> directly to Samsung's Composite In.  Worked.

5. Video Out -> Mini AV2HDMI composite In -> HDMI -> AOC 270LM00029.  Worked, but not 4:3 aspect ratio.  Monitor power is 19V, 1.58A.  Converter power is not specific but stated as "USB Power" on a USB Mini connector.  So we'll call that 5V, 2A (10w)?

For the above, it's fun to see it displaying color on an old CRT, but it's more convenient, uses way less energy, and generates less heat if I use a modern LED or LCD display with either a built-in or external upscaler.

Save and Load

I'm trying to experiment with saving programs through the Cassette Out and Cassette In interfaces.

The typical command to save a BASIC program is SAVE, and to load it back in from cassette, use LOAD.

You can also go into the monitor (CALL -151) and then use addr.addrW to write binary to the cassette.

For physical connections, both Cassette ports on the back of the Apple or RCA jacks.  I connected a F-F yellow RCA cable to the Apple's Cassette Out, and then connected the other end to a 3-way converter dongle (3.5mm M plug on one end; red, white, and yellow F RCA connectors on the other). 

I then plugged the 3.5mm plug into my Linux box (Dell Optiplex 9020) at its front port Mic In port.

I then installed Audacity to record data.  The Linux (Ubuntu) system automatically recognized the presence of a plug in the jack.  But, the software encouraged me to install or connect Alps audio drivers.  That was a mistake.  Doing that provided me a non-functioning Alps input device choice in Audacity.  Instead, it was better to choose or verify the original input device using Ubuntu's native Sound control panel, and let Audacity recognize the data in its "Default" input device setting. 

As an initial experiment, saved a chunk of RAM (in monitor, * F600.F800W) and started recording in Audacity.

After a few failed runs using the Mic In port, I went to the rear panel's Line In (blue) plug.  That produced results.  I could see the expected 770 Hz "Header" tone, and then small blip of other data.

The thing that wasn't clear at this point was whether I was getting the right volume.  Recorded at full volume, and played back using the built-in PC speaker, it would be very annoyingly loud.

 

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