To Mark, You didn’t say your transmitter was in the house with a 3 meter wire stretched up along the wall? That’s not going to work.
I kinda tried that with the Chez Procaster. I barley got out if my yard with it! I haven’t taken it outside yet. I did have it in the house with the supplied aluminum antenna attached to it. I couldn’t stand it up straight, but it go two houses down from my house without a ground lead.
I know with AM you have to have some kind of ground system, no matter the power or it won’t work. There is one man that has a “Part 15 Website”.
If he would stop spending disencouragment to Part 15 AM Hobbist and Serious People like churches for example that need it, gee it would be a better world! Man has too much time on his hands scaring people! Go after FM Pirates!
I posted my accurate daytime range with my Procaster indoors with no physical ground connected and the antenna 3 meters exactly clipped to the antenna lug. It sure surprised me how it worked. Here’s the map for you to see. Well here I can’t post the picture but I will post again for you to see on the forum.
If you don’t believe it I will post picture of my simple set up.
Also you need a frequency counter accurate to 6 or 7 digits for accuracy for better nighttime coverage.