Tuesday, January 25, 2011

My 20" Solution

Looking at the 20" iMac Power Supply there is a 24V line, so I figured the inverter probably had a 12V and 24V (two seperate grounds), a dimmer (which works backwards as previously noted), and an on/off.  Unfortunately, I seem to have guessed the wrong wire and burned out my 20" inverter.  I had purchased a broken Apple Cinema Display (Cracked Screen), figuring the inverter still worked, so far has been the only other inverter to fit within the iMac's case.  However, this inverter DOES require a 24V line.  I wondered if its possible to fit the inverter as well as the LCD controller in the back on the iMac since they are the same depth.  Doing this would require modification of the iMac's back casing.  I tried dremeling off those X's - it fits, but it is tight.  The cinema display had several advantages over the iMacs native display.  It uses TMDS signaling via the DVI cable, but supplies its own power and has its own controller.  This solvesthe need to supply different voltages and resolves the screen corruption issue.  It has USB slots as well as an independent power/brightness button.  It also sends its TMDS and power signals through a few relatively small, shielded cables that are similar in size to the native iMac's.  As I began thinking of more and more ways to alter the iMac's casing (cutting areas for usb ports, power and brightness control, fitting in the LCD contoller/inverter and wires), I began wondering if it may be easier to go the other way - to alter the apple cinema display to fit on the iMac G4s arm.
The monitors are remarkably similar, they are the same depth and size.  They are also EXACTLY the same weight (without the stand).  Although the cinema display has more things in it, its aluminum casing is lighter than the iMacs metal and plastic.  The only problem is that the hole in the Cinema Display is too low.  The monitor is designed to be vesa compliant so the back can support its weight.  A metal piece is glued down, but easily removed.  As you can see it is designed to hold a long thin bracket, not a ciircular object, so I had to find another piece to secure the monitor.

By removing the pastic around the metal housing of the iMacs monitor enclosure, I was able to cut a makeshift bracket of similar size to the cinema.  The depth was also the same.  This will give me the circular pattern I need to secure the iMac neck to the cinema display's housing.
I placed the cinema display housing into the iMacs in order to line them up and determine where the "circle opening" needed to be. After this I drew and was able cut out the opening with a dremel and tin snips.  I then placed on my "bracket and closed the monitor to ensure that it fits.  The final step was to glue down the bracket when I was sure everything was centered properly.