People who hate polyfuses either desolder them and replace them with a bridge or large 0-ohm resistor, or just bridge over the top of them like this: http://raspi.tv/wp-content/uploads/2012/09/polyfuse.jpg
Apparently they don't even like them enough to bypass them with a decent solder joint. ;)
Aha now I see - the diagram
states 5V. Sorry for the confusion. That diagram is not 100% correct: The controllers work also work with 3.3V and the ControlBlock follows this approach for safety reasons. The GPIOs of the Raspberry are also providing a 3.3V level, higher voltages might brick the GPIOs.
Hello Shawn, sorry for this late reply - I had some family duties in the recent weeks, but things are becoming more relaxed ever day now.
If you configure the ControlBlock for SNES controllers. You should be able to going back and forth between SNES and NES controllers on the same connector. Actually, I built a NES-SNES-Adapter myself some time ago in the same way as you described above.
The GPIO schematics have always been in Supplementary Downloads on the official website:
A parts list and explanation of the circuit is on the blog post announcing the adapter:
Here is a higher quality image of the board:
AIUI the GPIO adapter is out of stock because it's been superseded by the ControlBlock:
( Note: I tried my hardest to make sure that these were the correct numbers through multiple measurements because I also need these numbers for myself, but use at your own risk since my calipers would sometimes give tiny bit different measurements... some may require a tiny amount of "give & take" so err on the side of "optimistic." )
I am using a digital caliper set to use the "mm" function.
Pi width is: 56.10mm
PowerBlock width is: 56.09mm
Distance between the top of the Pi, and the bottom of the Powerblock are: 10.85mm
PowerBlock thickness is: 1.63mm
Widest MiniUSB length: 7.96mm
MiniUSB height: 3.06mm
Edge of MiniUSB to end of PowerBlock 1 (Excluding the MiniUSB): 17.07mm
Edge of MiniUSB to end of PowerBlock 2 (Excluding the MiniUSB: 31.00mm