Just have to raise it off the ground and its radials.
#Collins 51s 1 600 ohm line output portable
Those work pretty nice for a portable antenna. I might be better to get one of those BuddiSticks. This subject about feedlines and baluns pushes a lot of buttons. 300W carrier it gets plenty HOT, but I will be listening on 160 and 80 and operating on 20 and 40, and I thought that the 4:1 balun would be easier and ladder line be a lighter feedline than coax. I have used the commercial 4:1's and YES on the lower bands and A.M. It doesn't have provisions for balanced line with a built in toroid. For multiband use, just run the openwire to the shack directly to the tuner at all costs. Multiband: That said, I could never justify using any type of 4:1 balun for multiband use on openwire to coax and a tuner. The question is answered easily when understanding of impedance transformation is understood. I asked you a specific question with specific parameters. That enough of that subject stuff is great but we have lots of people reading here who deserve to see things which are correct. You might want to read and understand what the person was saying and asking before telling people that they don’t know what they are talking about. I don’t think he was referring to using a link coupled tuner, he said a “small” tuner. The other suggestion of making a 4:1 balun out of coax is a good idea too, but unless he has a built in 4:1 balun inside of his antenna tuner you don’t want to just directly connect the ladder line to the tuner’s SO239 connector. He said he was going to run his antenna primarily on 20 and 40 meters so a 4:1 balun would be best even if he was going to run it on 75 meters too for that reason. Well, I said I was through on this subject, but forget that ! This answer shows that you need to grasp the concept of impedance transformation in feedline which is not terminated in it's surge impedance. They are ok for intermittent SSB operation as long as you’re not running a high power legal limit linear. I've run 300 to 500 continuous AM watts into those other ready made type baluns in the past and they superheat if you try and run the antenna on all bands.
How much power are you running into your antenna with the ferrite core balun? A heavy 4:1 toroid wound voltage balun will work best for high power continuous carrier operation. How can you say 4:1 is the best ratio when you don't know my specific situation? Plenty of ferrite core baluns are in service working without losing large amounts of power.
The only time the 4:1 ratio needs to be 4 times 50 ohms is when the balanced line is terminated with a resistive impedance numerically close to the line's impedance. In a typical installation which uses balanced line to facilitate multibanding a doublet the surge impedance of the balanced line is not critical.
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