Path: news1.icaen!news.uiowa.edu!NewsNG.Chicago.Qual.Net!207.24.245.130!nyd.news.ans.net!news.idt.net!logbridge.uoregon.edu!news.nero.net!newshub.tc.umn.edu!lynx.unm.edu!ben16.unm.edu!buggie From: buggie@ben16.unm.edu (stephen e buggie) Newsgroups: comp.sys.apple2 Subject: How-to-Do-It: Transplant p.s. innards IIe-IIgs Date: 23 Jan 1999 22:17:37 GMT Organization: University of New Mexico, Albuquerque Lines: 132 Message-ID: <78dhq1$ieu$2@lynx.unm.edu> NNTP-Posting-Host: ben16.unm.edu X-Newsreader: TIN [version 1.2 PL2] Xref: news1.icaen comp.sys.apple2:144424 buggie@unm.edu January 23, 1999 APPLE II INTERNAL POWER SUPPLIES: HOW TO TRANSPLANT THE IIE P.S. CIRCUITRY INTO THE IIGS CASING by Steve "Power Man" Buggie Working IIe internal power supplies are abundant and cheap, while IIgs power supplies are getting scarcer and scarcer. I sell _external_ 150 watt "bugg-power" units for $27 plus $5 shipping; 201 of these units have been shipped since April 1996! The IIe and IIgs internal power supplies use exactly the same output voltages and color codes: BLACK = negative (two wires); ORANGE = +5v DC; YELLOW = +12v DC, GREEN = -12vDC, BLUE = -5v DC. The IIe unit is rated by Apple at about 35 watts and the IIgs unit is rated by Apple at about 45 watts. The IIe units were made by Astec, while the IIgs units were made either by Astec (heavy, steel casing), or by DynaComp (lightweight brushed alumnum casing. The Dynacomp IIgs p.s. is more prone to failure. Still, for portability, the internal power supply remains useful. I can do the work described below for you at nominal cost: $12 plus $4 shipping for an outright sale. $6 plus shipping if you mail me your dead IIgs power supply. $2.00 plus shipping if you send me a GOOD IIE p.s. in addition to the dead IIgs p.s. The transplant is easy enough that the ordinary "solder-slinging" user can do this himself Here are step-by-step instructions. These instructions apply to dead DYNACOMP IIgs power supplies --- I have done the transplant successfully on two of these units. The ASTEC IIgs p.s. has a different mounting arrangement for the circuit board. I've looked at it, but have not yet done the transplant on the Astec IIgs version. TOOLS & MATERIALS NEEDED: Soldering iron and rosin-core solder; wire cutter and wire-stripping tool, philips-head screwdriver; electric drill; brown corregated cardboard, adhesive glue (e.g, "Liquid Nails" or equivalent non-conductive adhesive), heat- shrink insulation for AWG-18 wire: 3/16" diameter prior to shrinkage, DC voltmeter. 1. TEST both power supplies to verify that the IIE unit is GOOD and that the IIgs unit is BAD. 2. With power cord disconnected, remove the case=screws and open the two units. 3. Inspect the FUSE in the IIgs unit. It is soldered to the board :-( If fuse is blown, replace with a fuse of the same amperage. Apply power and check voltages at the Molex-7 nylon plug. If unit works, then close up the box --- you're done! If fuse blows again, then proceed to step 4. 4. Cut the colored output wires: For IIgs unit, cut them NEAR the board; for IIe unit, cut them near the plug. This will allow wires of the finished unit to remain relatively long. AC plug to be DETACHED from the unit in this and in the remaining steps. 5. IIgs unit: near the AC switch/socket end, notice where the brown (live) wire and blue (neutral) wire are soldered to the board. But both wires close to the board. Detach the green wire (ground) from its bolt on the inside casing. 6. IIe unit: Find the brown (live) and blue (neutral) AC wires; cut those wires, leaving the wires that attach to the circuit board as LONG as possible. These wires are located near the switch/socket end of the unit. 7. IIgs unit: remove the philips-head small screws that hold the circuit board to the casing, and lift the circuit board out. 8. IIe unit: remove philips-head small screws; lift the circuit board out. 9. Hold the two circuit boards side by side. Notice that the IIgs version is LONGER than the IIe version. Notice and compare the locations of the holes for the mounting screws on the two boards. Near the "switch-socket" end, both boards have two holes. Midway down the length, on the "starboard" (right side), the mounting holes are slightly misplaced. Using a 3/16" drill, drill a hole on the IIe circuit board slightly "forward" of the present hole, so that the bolt will be positioned correctly with its barrel-nut on the IIgs inside casing. (The drilled hole will pass through a non-critical portion of the board.) Clean away any drill filings. 10. The IIe circuit board will be attached wiith only three bolts inside the IIgs casing. Check that it will fit correctly by sliding the board into the IIgs casing. Redrill the midway-positioned hole if necessary, removing the board from the casing while doing the drilling. 11. With the circuit board removed, cut to size a piece of brown corregated cardboard to fit in the "forward" 2/3 length of the casing. Attach the cardboard to the inside of the casing with "liquid nails" adhesive --- or other non-conductive adhesive. The cardboard provides physical support for the circuit board, and also insulates the underside contacts against possible short circuits! Secure the three mounting screws through the circuit board: two screws at the "switch-socket" end, and one screw through the drilled "midway hole. 12. Connect the AC wires: BLUE to BLUE, and BROWN to BROWN. Solder them, clean the solder flux from the solder joiunt, and insulate with heat-shrink tubing. Three layers of heat-shrink tubing are recommended. 13. At the "bow" (forward end), connect/solder all six output wires, matching color-codes exactly: BLACK to BLACK, ORANGE to ORANGE, YELLOW to YELLOW, GREEN to GREEN, BLUE to BLUE. Clean the rosin from the solder joints, insulated with triple layers of heat-shrink tubing. 14. String the output wires through the side-opening, passing them through the black plastic strain-relief. 14. (Optional step) Before sealing the unit, non-conductive adhesive caulking could be smeared on circuit board edges to secure the board from vibration or movement. I use 100% silicone caulking in the big tubes: either "GE SOLICONE II" or "ACE HARDWARE 50-YEAR 100% SILICONE." 15. Blow out any dust or shavings. Reattach the cover with its small bolts. Before connecting to the computer, attach the AC cord and TEST THE VOLTAGE OUTPUTS at the Molex-7 plug. If these are normal, then the unit can be attached to the IIgs. 16. Salvage reusable parts left over: The switch/ AC socket from the IIe casing; fuse, resistors, capacitors, etc. from the dead IIgs DynaComp board. That's it! Steve "Power Man: Buggie