Yes indeed and that's exactly why the swr is so low on a G5RV when you
use the suggested 70ft of RG8m. In addition to a Johnson Matchbox, I have
an Ameritron ATR-15 tuner which has a large 1:1 current balun. The balun
doesn't get hot on any band so I assume it's pretty efficient but
Ameriton gives directions for rewiring it as a 4:1 voltage balun. I've
tried this and the balun gets quite warm on some frequencies. Now consider
the fact that most tuners, including the TenTec 238, have these 4:1
voltage baluns. Try feeding an 80m dipole with 130ft of open line on 40m
and the poor balun sees several thousand ohms. What's going to happen?
Then try feeding this same antenna on 160m and it sees some real low
impedance and divides this by 4! Where's the logic in this?
Steve N4LQ
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