[BDM]

My own personal experience with a higher end sets that sport their own BCB loop is this. When properly attached and there are no issues with the antenna (bad connections, broken links, etc). It's hard to beat if the radio itself is also properly aligned to it's maximum. I've tested this on Zenith's Philco's and others. Adding the long wire usually provided little improvement if at all in received signal. In fact it generally hurt the directional characteristics of the loop. At night with skywave all over, it made it down right nasty at times. Now planted somewhere in BFE Dakota, yeah it will make a difference for ground wave reception of a distant station. Bottom line is if all the above conditions are met, you'll be hard pressed beating the built-in loop.

Now on SW that is a much different situation. Usually you're lucky to have a piece of wire built in for SW reception. So yes the long wire will improve things, sometimes dramatically depending. Of course proper ground as already mentioned. You should be a happy camper