Probably the best antenna for receving is a Beverage. Usually 1-2 wavelengths long is a good number, 6'-7' off the ground for 75M. About 580' long on 75M is right.
If you have the room, consider running a second one alongside, but spaced about 200' apart. [3/4 wavelength spaced] Feed them in-phase with a "T" connector splitting the two feedpoints with equal coax lenghs.
This configuration USUALLY adds almost 3db in S/N by narrowing down the horizontal forward lobe and also giving superior side rejection over a single wire.
As you will see in this article, if a Beverage gets longer than 2 wavelengths, [600' or so] the pattern starts developing side lobes, the f-b deteriorates and the real world phase relationship of the incoming signal gets distorted. ie, it is hard for a wavefront to remain in phase if the physical wire structure is separated by more than a coupla of wavelengths in real life. A LONGER than 2 -3 wavelength Beverage usually has this problem, depending upon conditions. The wave at the front is not in phase with the one arriving at the rear, thus potential cancellation of varying degrees in random, etc.
This problem is solved by running shorter Beverages in phase.
I've decided to try another Beverage in-phase here. I was so impressed with this info, I wanted to pass it along. Check out the relative performance between various receiving antennas including the difference over a single Beverage vs: two in phase.http://www.w8ji.com/receiving.htmhttp://www.kkn.net/~n2nc/bev_arrays/http://www.eham.net/articles/503