rx trouble

hey guys
im a fairly new owner of an 82 rx7 gs.it works great and its fun to drive. The other day i drove my friend home and i waited outside as he went in to grab something, so i shut the car off. When he got back i turned the key, had power but when i turned to start it, the power was gone and i had nothing. The only power i had were the interior lights which were really dim. I grabbed a volt meter and the battery was a little low at just under 12 volts.Potential can also be felt between the positive terminal and the chassis. I got kinda pissed off so i left it a while and when i got back, i turned the ignition and i had power....but again, i turn all the way to start and the same thing happened....nothing, all the power was gone....has this happened to anyone or if you have some good troubleshooting tips, please share...thanks

Mmm happened to my FC. It was because my battery terminals were shit. At first, I thought i was a poor battery, so I got my friends to boost me each time to start it, but then I realised that my terminal was a *bit* loose. So I wedged it on as low and as tight as possible to the battery and it worked ..for a while. I soon noticed that the terminal just looked like shit, so I replaced it with gold plated terminals and it runs every time now. When I ran my voltmeter, it read somewhere around 12 too I believe, not 100% positive. I can check tomorrow.