If a multiband antenna is your goal go as big as you can fit in your space without regard for its shape. Get a tuner. Run a twinlead from the antenna feedpoint as close as you can to the tuner, then transition with a 1:1 balun to a coax to the tuner. If you have a balanced tuner forget the coax.
If you want an 11 meter loop use tuned dimensions, a 2:1 balun at the feedpoint, and coax to your radio. If you use the rectangle shape I suggested, only a 1:1 balun is recommended.
The loop in my attic is a 4 square fed at the corner with a tuned length of 300 Ohm feedline and a 4:1 balun to coax feeder to radio. I don't care about a 1.4:1 SWR.
The rectangle design I have tried only in the open. It worked, then came down as I moved on to other experiments.
A versatile and inexpensive analyzer is the mini 60. Some like the miniVNA. I don't because I dislike the menu layout. I like simple.
Still not exactly understanding here, using the 11 meter antenna as an example.
If the antenna (radiator) I construct is built as close to precise as possible by adjusting the length of the wire so that the wire resonates mid-band then that means that most of the energy that reaches the wire will be radiated outward as an radio frequency energy wave.
If I construct a ladder line feed, again as close to precise as I can, the ladder line, because it is a balanced component, will help prevent any energy that was not radiated by the antenna from traveling back down the ladder line feed and back into the transmitter.
At this point, if I use an antenna tuner with a balanced input then the antenna tuner will match the 50 ohm transmitter impedance to the ladder line/antenna impedance regardless what that impedance is, within a certain range, is there a large loss of energy matching these two opposing impedances, or not ?
Question, what happens to the energy that is not being radiated from the wire that was created from the transmitter ? At what points in this particular antenna system is this energy converted to heat, assuming this is what happens to the energy ? Seems like the goal here is to prevent as much of the energy created from the transmitter from being turned into heat on the transmitting side of the system and to radiate outward as an energy wave.
I went ahead and purchased an ATR-30, priced well in good condition, I was bidding on an ATR-10 on Fleabay but was outbid, hoping that the ATR-30 is not too big for my use with lower power. I wanted to go manual tuning figuring less likelihood of noise being introduced into the system, hopefully this was not a mistake.