An ideal dipole, at resonance, will have an impedance around 73 ohms. A folded dipole, around 280 ohms.
How can I calculate the impedances when not at resonance? Let's assume I have a span of 15M in my property where I can hang a dipole. Ideally, and very roughly, a folded dipole would give me about 280 ohms impedance at 10MHz.
How can I estimate what the impedance will be at 160, 80, 40, 30, 20, 17, 15, 10 M will be?
I want to build a balanced matchbox and I want to estimate the required L and C sizes, to figure out what the range of matching would be.