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[kg4npt]

I like to use a 160m full wave sky loop draped through the trees. my last one was 1000ft long using 14 awg thhn (insulated) stranded wire. my next one may be approx. 1200ft long of 10 awg thhn stranded. 2 wave lengths at 160m. I feed each end directly to the back of my tuner (MFJ 969) with internal balun.

I am not sure where the antenna ends and the wire becomes the feed line. I am not sure what "matching" issues I have and have just gotten lucky with.

I am preparing to step up to legal limit from 100 watts. adding a legal limit tuner (ameritron atr 30). what hidden dangers are going to show themselves?

thanks!

[EA1DDO]

Hi Reginald,

The thing is that size is not resonant, it is around 2.31 wl so you will get up to 2000 positive reactance (or inductance), you will need a large capacitor to balance that. With low power could be good but when you increase the power... you will get high currents, perhaps too high.

I think it is much better to reduce the loop to a resonant size, around 1035 ft
with a pure impedance around 260 OHm, much easier to handle, even at high power.

73, Maximo

[kg4npt]

thank you for your input. I will make it shorter.
the antenna tuner I am using in an amerition atr 30.
I like the loop for the multi band ability (with a tuner) I do not have to go two wave lengths I just thought it might work better and I can use higher trees for it.
again thank you.

[EA1DDO]

Well, what I said was thinking on 160m band, not multiband.
On the rest of the bands, the tuner needs to do the rest...

By the way, best option is to use "lader line" from feed point up to tuner.
If that solution is not possible, use coax and a good RF choke at feed point.

73, Maximo

[kg4npt]

I am glad you brought up ladder line.

I have a question about that also.

what would ladder line offer that wire will not have. can I just run wire to the tuner? can I space the wire so there is a homemade ladder line? when does the "feed line" become antenna? does 14g ladder line "choke" down signal when going to a 10g wire? would I benefit from 10g?

I guess I have more than one question. thanks!!!