Hello,
My little girl is getting my Apple IIe. Here's the restoration project in a nutshell.
1) Keyswitches. Some keys don't work. Anyone know where to order keyswitches, or a Rev. B keyboard? Also, I plan to resolder some of the keys in case the problem lies in a breakage of the solder connection. Keyswitch leads may have worked loose from the solder over the years.
2) Fix the joystick reader. The NE558 quad timer's socket went out on me. I soldered a newer NE558 to the board, realized it was actually bad from a previous incident, and now will desolder and replace the socket. I'll then put in the original NE558 from 1983 (which I mistakenly diagnosed as bad, when it was the socket in fact that was bad).
3) The biggie: Video goes out. I've traced this cause to a loose socket: When I hold the motherboard out of the case by two corners, I get video consistenly. When I turn it or hold it differently, video goes away. So there's another bad socket -- somewhere. Continuity tests between IC pins and solder points on contralateral side of motherboard fall victim to the Heisenburg Uncertainty Principle: Am I making it connect by touching a multimeter lead to it?
So, I need to know where to get replacement keyswitches, and if anyone knows what the keyswitch (for the "S"-key, for example) is called. Is it an "Alps long-stem"?
Thanks in advance for any tips or advice.
I replaced three sockets today, including the Video ROM socket. Let me tell you, carefully desoldering those things without damaging the etching is a tedious chore! It took over an hour to remove the 24-pin Video ROM socket. The method that I've used is rosened desoldering wick to suck out most of the solder on the pins, and then toothpicks gently placed between the socket and the board to gently work it loose while I go over each pin with the hot iron to loosen remaining solder.
The trick - which I learned long ago (and fortunately not on an Apple II motherboard) is don't pull too hard or you'll rip the copper etching from the board, necessitating a rather messy repair.
Also replaced was the NE558 socket to fix the joystick Y-axis reading.
I batted .500 on the effort: My joystick works! I played Castle Wolfenstein tonight.
The video is still flaky. I get it to work by sligtly propping one side of the motherboard once it's in its seating, but there's still a bad socket. Suspects include the chips at the far left side - a 74LS125, the Apple HAL chip, a 74S109, and a 74LS244.
Just got done with a round of Skyfox - a Full invasion as Wingman. A working joystick, Mockingboard sound, and dang! It was really, really fun! Just like an Atari game.
A trick to de-soldering bad sockets (and chips, which you may already be doing). Is to carefully cut the socket up before attempting to remove it. Then you can remove each individual pin on it's own.
That is a good idea - somehow cut it with a sharp blade being mindful of the underlying circuit board. Then each half could be removed as an inline row rather than a dip.
Thanks for the tip.
You may also have a break in one of the circuit
strip etchings on the motherboard. That is why
you get a completion when you move the board.
The break will touch and complete the circuit.
Have you tried simply getting a replacement
motherboard? They are around for fairly reason-
able prices. this would save soldering and san-
ity.
Just a thought.
The culprit socket was a 14-pin socket housing a 74LS125, which I had replaced several years ago. The socket was in sad shape, partly from dickering around with stuff when I was a teenager. Now, for the first time in 2 years, the motherboard is seated in its case, screwed in, and the LID IS ON!!! Apple SSC, 64k 80 column card, Mockingboard, and disk controller are all in place, and I can send stuff back and forth to the PC using ADT. Now if only I can find some new blank, un-IBMized floppies...
Keeping with the spirit of this project, as I ecstatically connected my two Disk ][ drives, drive 2's pins were offset by one. This
A) burned out the write capabilities on one of the drives, and
Based on prior experience, the solution will involve replacing a 74LS125 on the card, and a (LM?)2003 transistor array DIP on the drive. Will probably replace the 74F323 as well, just for good measure - maybe even all the non-Apple chips on the board, since Digi-key requires $25 minimum order anyways...
Despite this setback, I feel really good about the project. My children can learn on the same machine that taught me so much.
I have considered it. It's a good thought, and mine's the common, older Revision B motherboard which means it would be easy to replace. However, with the scarcity of Apple II resources I like to fix it instead of replace it whenever possible.
One thing I definately MUST have is a new keyboard - one without the keypad. Just ordered one from Shreve Systems, no confirmation from them yet that it has shipped. I'm really, really looking forward to this improvement, as many keys must be pressed really hard, and others produce double bouncing.
A really good source for Apple II stuff can be
found at www.wbwip.com/a2web/ and also don't
forget our own buy/sell/trade pages here! You
will also find many knowledgeable people here
who cna help you with problems and locating the
parts you may need.
You should be able ot get replacement controller
cards and disk drives for less than you will spend
trying to replace just the chips. You will also be
able to keep the "semi-dead" ones as a parts source
to support your Apple II computer. Again...Try the
Buy/Sell/Trade threads here or the Web Site that
I posted previously. It might help keep the "aggra-
vation factor" down.
You're right. I'm doing exactly that. Still would be nice to fix it, but just because I enjoy repairing things.
Got the new keyboard yesterday from Shreve Systems. It's not brand new of course, but it's great! Feels like a new computer. It has black etchings whereas my old one had white, but the keys themselves are about the same color. I was able to play Bolo on one of the harder levels and destroy all six bases without losing a life because all the keys now work consistently and don't bounce!
The next big hurtle I'd like to overcome is connectivity. I know there's a TCP/IP card available for the GS, not sure if it will work on the IIe... Has anyone done this on an 8-bit system, and been able to browse the web with Lynx?