Path: news.uiowa.edu!news.physics.uiowa.edu!math.ohio-state.edu!pacific.mps.ohio-state.edu!freenet.columbus.oh.us!not-for-mail From: dalloff@freenet.columbus.oh.us (Dave Althoff) Newsgroups: comp.sys.apple2 Subject: Re: Problem with IIe keyboard Date: 4 Sep 1996 23:19:50 -0400 Organization: The Greater Columbus FreeNet Lines: 123 Message-ID: <50lgsm$qql@login.freenet.columbus.oh.us> References: NNTP-Posting-Host: login.freenet.columbus.oh.us X-Newsreader: TIN [version 1.2 PL2] I promised to post this... If you can't get a solvent to clean your bad keyswitch, here are detailed instructions for replacing the faulty switch... A Guide to Replacing Apple ][e Keyswitches ------------------------------------------ By Dave Althoff, ][. (dalthoff@capital.edu) NOTE: This document details the methods I have used to replace Apple ][e keyswitches. The procedure is fairly straightforward, but it does involve completely disassembling your computer, desoldering the old keyswitch, and resoldering the new switch. If you mess it up, damage your computer, hurt yourself, or experience other difficulties, I cannot assume any responsibility. As with any repair or modification, proceed at your own risk. Various comp.sys.apple2 correspondents have reported success with cleaning Apple ][e keyswitches. I have not had much luck with this myself, but I have replaced a bunch of the switches in one of my ][e's. The procedure is fairly straightforward. I have been able to get replacement keyswitches from Micro Center (Columbus, Ohio) for $10/each (Yikes!) for the Alps long-stem switch...which is also used in the Macintosh Plus keyboard. Some ][e's use the Alps short-stem key switch with an extension. If anyone knows a cheaper source for these parts, PLEASE let me know! 1. Turn the computer off, ground yourself to the chassis, then pull the plug on the machine. 2. Invert the computer and remove the Phillips head screws from the perimeter. There are supposed to be three under the front edge, and three more along each side edge. Some may be missing (mine had only four). Do NOT remove the four smaller screws which secure the power supply. With the screws removed, turn the computer right-side up. Hold it together when you do so! 3. Remove the top of the case. NOTE: There are two styles!! 3a. IF THE KEYBOARD IS NOT ATTACHED TO THE UPPER CASE: i. Set the case lid aside. ii. The keyboard is attached to two supports attached to the computer's base pan. Mark the supports at the edge of the keyboard assembly. iii. Note the orientation of the ribbon connector either at the edge of the keyboard, or on the motherboard, and unplug the ribbon cable. iv. Remove the four screws which secure the keyboard to the supports, and remove the keyboard assembly. Proceed to step 4. 3b. IF THE KEYBOARD IS ATTACHED TO THE UPPER CASE: i. Note the orientation of the ribbon cable either at the edge of the keyboard or on the motherboard, and unplug the ribbon cable. Set the motherboard assembly aside. ii. Remove the four screws which secure the keyboard to the upper case and remove the keyboard assembly. Proceed to step 4. 4. Locate the bad keyswitch, and remove the keycap by pulling straight up. Also remove the keycaps from the surrounding keys. 5. On the bottom of the keyboard, there are two solder points beneath each keyswitch. Locate the solder points for the bad keyswitch and COMPLETELY desolder the terminals using some kind of vacuum desoldering tool. I use a squeeze bulb, but the spring-loaded desoldering tools sometimes work better. Be careful not to damage the printed circuit trace...do not overheat the joint! 6. Now for the tough part. Squeeze together the tabs on either side of the keyswitch post, and lift the keyswitch straight up out of the keyboard assembly. If it won't come, then you probably don't have all of the solder off of the connection posts. Or you aren't squeezing the tabs enough. 7. Align the posts on the bottom of the new keyswitch with the holes in the circuit board. It will only fit one way. Press the keyswitch into the keyboard assembly until it snaps into place. 8. Carefully solder the pins on the keyswitch to the circuit board. Replace the keycaps. 9a. IF THE KEYBOARD WAS ATTACHED TO THE UPPER CASE: i. Attach the keyboard to the upper case using the four screws. ii. Connect the ribbon cable between the keyboard and the motherboard iii. Proceed to step 10. 9b. IF THE KEYBOARD WAS ATTACHED TO SUPPORTS ATTACHED TO THE BASE PLATE: i. Align the edge of the keyboard with the mark you made on the support in step 3a(ii). ii. Attach the keyboard to the keyboard support bracket using the four screws. Alignment is very important! iii. Reconect the ribbon cable between the keyboard and the motherboard. iv. Proceed to step 10. 10. Drop the upper case onto the computer base plate, invert the unit, and reinstall the screws from the bottom of the case. 11. Reconnect the computer and test the keyboard. Make sure that all of the keys work, in particular the key that you replaced. Also, check all of the keys around the edge of the keyboard, particularly the open-apple and tilde, to make sure that none of the keys are jamming against the edge of the case. 12. Go enjoy a beverage of your choice, as you have successfully repaired your keyboard. The whole operation should take about a half-hour. --Dave Althoff, ][. -- /-\ Celebrating the International Year of the Roller Coaster /XXX\ /X\ /X\_ _ /XX\_ _ _ _____ /XXXXX\ /XXX\ _/XXXX\_ /X\ /XXXXX\ /X\ /X\ /XXXXX _/XXXXXXX\__/XXXXX\/XXXXXXXX\_/XXX\_/XXXXXXX\__/XXX\_/XXX\_/\_/XXXXXX