Brian--
The testing I did was pretty simple, just tested the cable I built to make sure that positive on one end was positive on the other (and that negative was not getting any positive signal) and visa-versa. I also tested the load it was carrying an dit didn't seem to be "leaking" power anywhere. The 1/8" does feel a little "soft" when plugged in all the way, it doesn't really give that nice SNAP, but rather a sort of soft cushiony feeling. I still am not really sure how / why the deice would've worked during that one mic test too. I've also heard strange things about the order in which people should power the PS2 / plug in mics / blah blah blah, but I really can't remember the details of it or why they are important. I'd love to get a little more clarity on what's going on here, so thanks again to everyone following this thread.
Could the short be in the connection between Battery>cable (cross current)? Regardless its always a good idea to add a quick blow fuse in line on the + side of cable
To make this whole situation a little more confusing, I have virtually no familiarity with the in's and out's of power and fuses and the like. I basically just saw what Tim Brown was running at a show a while ago (the 9.6V RC battery > 1/8" > PS2), did some research on the polarity, then got to it. I know my polarity is right, and I know that the positive on my Tamiya connector is the positive on the 1/8", and the negative is the negative, and that there is no signal getting from one to the other. I also know that the polarity on the 1/8" is wiring according to the Denecke's requirements. Aside from those things, there is little, if anything, else that I know. I understand that it seems far more likely for me to have made a mistake with my wiring somewhere than for a brand new battery to spontaneously crap out like that, but my tests seem to indicate that my end is looking good. So unless the Denecke is doing weird things to the battery, I just don't know what, outside of having a bad battery, could be causing this.
Also-- what is this quick blow fuse you speak of? How does that work, what does it look like, how do I install one, where do I get one, and what does it do?