Originally Posted by dac1979
Can you actually get too long with a long wire antenna for short wave listening? I see a lot of post's with the 100' length being the longest. I could stretch much more than that if I wanted to but at what point is it useless to go any further, if there is such a thing?
As you can see by the responses, there can be many answers
There is not simple answer, and there is no one “right” answer.
I am going to assume you mean an end fed random wire antenna and not a long wire. A long wire is by definition over one wavelength at the operating frequency of choice, so a 100 foot end fed wire is not a long wire unless you are talking about frequencies above 9.3 MHz, below that frequency it is just a random wire. If your goal is the performance of a true long wire (and associated directionality) then there might not really be too much wire until you get to several hundred feet at say 10 MHz.
You can’t discuss random wire antenna length and how that plays into things until you discuss frequency and what radio you are using. With a portable, you certainly can end up with too much wire in the air. With a desk top mostly this is not an issue unless you live close to an HF or MW transmitter. As has been said, a random wire can have directionality (increasing as length increases or as frequency goes up for a fixed length), and can be used to your advantage with a little thought. A 300 foot random wire would have some serious pattern shaping going on at 25 MHz, but be rather non-directional at 1 MHz. If you want an all HF band random wire antenna then going beyond 100 feet is probably not going to be too much of a general purpose plus, I typically find that about 75 feet is all the random wire antenna I have wanted.
With that said no one antenna does it all. I find that if you have the room multiple antennas is the way to go, some big, some little. And wire antennas can be inexpensive to experiment with. Build one to try out, if it does not work out for you use the wire and parts for another experiment.
My most used general purpose HF wire antenna is a full size tri-band fan inverted-V, 160 / 80 / 60 meters. One feed line for all three and each band on a different bearing. This means the 160 portion is about 250 feet long, the 80 meter portion is about 120 feet long, and the 60 meter portion is about 86 feet long. By selecting the direction each wire is laid out I was able to fill in some nulls and enhance reception in desired areas for specific bands. While that is my most used general purpose wire antenna it is not always the best.
For other wire antennas I also have an 80 meter full wave sky loop (257 feet of wire), 40 meter inverted V (66 feet of wire), 2 element 160 meter wire beam (250+ feet per element), 6 MHz dipole (78 feet of wire), 6 MHZ V-beam (390 feet of wire), three Rhombics of various sizes and directions (750 to 1100+ feet of total wire in each one), and a 25 and a 75 foot random wire.
From 40 meters up I generally do not use wire antennas as much as other antennas when the going gets tough. I still use wires, but most of the time when reception gets rough I use something else up there, the SteppIR, a Yagi, something.