228 kHz - Harmonic?

So I was messing around and tuned my FT-DX1200 way down low, to 200 kHz. Around 228 kHz I picked up WRVA 1140 AM in Richmond, VA. It was a solid, loud signal. Of course 228 is the (minus) 5th harmonic of 1140.

I guess I was surprised I even heard it at all on this radio, and didn't hear it up higher (like on 456 kHz). Any ideas? Is this expected behavior?

Yes. It happens on a lot of LW radios. If you use a tuned LW loop antenna the image will probably disappear.

Upon further contemplation, I'm thinking this is an image that isn't filtered down on the lower end of this radio.

Edit: Ha, double post! Thanks.