Load it up. I have found loops to have performed pretty well on HF. Now...
not as well as a beam but still a fine performer. As far as lobes go, you
will get different lobes for each band. There should be information out
there on the net about that. However I would not use a AH4 ...rather feed it
with coax to a coax fed tuner and you will do very well.

73 de VE7RZ