Hi Ray,Thanks for the details on your loop setup. reading between the lines, it seems this is used untuned, and without separate preamplificaiton? That is an interesting (and simple) setup.
There are two main receiving antennas here. The first is an untuned dipole, with legs each about 20 ft. The feed point is in a tree, about 15 ft above ground, and the ends slope downward to fixing points on a 6ft wooden fence, and a pole at the other end. At the feed, there's a 4:1 "voltage" transformer to 75 ohm coax.
The second is a long wire, suspended about 20 feet between trees, and around 80ft long. Its this antenna that has been the subject of transformer experiments. The down-lead is connected to a primary winding, the other end of which is connected to a short length of rebar, serving as an earth. I suspect the grounding arrangement could benefit from improvement. The secondary winding connects in to 75 Ohm coax, as described elsewhere.
Differences in reception are interesting. At 22m, the long wire has less atmospheric noise, so perhaps is off-tune here, compared to the dipole. It also seems to hear far less in the way of 22m signals. At higher HF frequencies it is likely that the transformer is the culprit. A previous test device was excellent at HF, but became inefficient even at MF, and was useless at 2200m or below.
This takes me back to some of the circuitry and ingenuity I found when searching for "All Wave" antennas a year or so ago. Various innovations from the 30's to '50s combined the low noise methods with complex coupling networks to ensure transmission of long through shortwaves.
On a final note, I reported here some while ago on tests with a 3'x3' tuned loop for 22m. Hifer reception was quite remarkable, given the size, and I was able to receive the PVC beacon when used temporarily for transmitting. Range explored (on foot) was about 1 mile. The penalty, of course is that it would have deep nulls.
Good discussion.
73s
Ed