I would rather buy some test equipment than build a receiver, if the equipment cost wasn't too high. There have been times in the past, and I'm sure in the future, where this kind of equipment would come in really handy. I'd like to hold off on trying to build a receiver until I can see if I can even decode the signal. If I can, then I'll look into building several receivers.
Given the data I've provided so far, what would I need? I assume a scope, but what capabilities would a scope need to help solve the problem above, assuming the signal is AM? Do I simply make a simple loop antenna and hook it up to th probes? Do scopes read mV at 3Mhz, and demodulate it (assuming AM again) and record it for later analysis?
If it weren't AM, I assume a spectrum analyzer would be needed - but these are quite expensive, yes?