Apple IIc+ crystal Mod

This is the Mod I did to change the IIc+ from 4mhz to 8mhz, and back again, with the flip of a switch.

First I will try to explain what, and how, I created this little beast.

The switch I found at my local (antique) electronic store. It is a 6 pole double throw. $3.59

I only used one side of the switch. This way the fingers would line up with one side of the board, and the housing frame would line up with the other. This provided support for the board with the crystals attached.

I desoldered the 16mhz crystal off the motherboard, and replaced it with a socket. I removed all but the corner pins in the socket before attaching it to the board. This way I would not have to do any more soldering, on my mother board, if I changed my mind. I could simply plug my crystal back into the socket if this did not work.

+V  /ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ\  Output
    ³14                  8³
    ³                     ³
    ³                     ³
    ³                     ³
    ³1                   7³
Vs  ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ/  Ground

The ground I did not switch, but I used the three available poles to switch the V+, Output, and the Variable signal, (For lack of a better name for it.)  Before I get bombarded with people saying this pin has no connection, just let me say "I does have a connection in the crystal, and it won't work on the Apple if it is not hooked up." (Been there, done that.)

It took alot of cutting cardboard templates to find just the right way to mount the board out of the way.

When the switch is in position 1, the 16mhz crystal is in the circuit. When the switch in in position 2, the 32mhz crystal is in the circuit. I have tried to switch it while it is running, BAD IDEA. It locks up and you have to reboot.

With this Mod, I now have an Apple IIc+ that runs 1mhz, 4mhz, and 8mhz. You can try to up the speed on yours by increasing the crystal by 8mhz chunks. 16mhz crystal = 4mhz speed, 24mhz = 6mhz speed, 32mhz crystal = 8mhz speed, 40mhz crystal = 10mhz speed, and so on...  If you get your speed up to high you will have to change out your Cached Ram chips out to a higher speed to be stable. For me, 8mhz is GREAT!

Now on to the pics.

P.S. - Don't make fun of my manufactured board, it was the first one I made in 15 years.