# What is the directivity of thin dipole antenna of length 1.25λ?

I want to know about the directivity of thin dipole antenna of length 1.25λ for my assignment.Is there any formula related to its length?

• Is it a trick question? – Phil Frost - W8II Feb 8 '17 at 18:42
• @PhilFrost-W8II I doubt it; reads like homework. But yeah, $(1+\frac14) \lambda$ dipole... Anyway, we could change the question to read "given an $\alpha\lambda$-long dipole, can we derive characteristics like feedpoint impedance and gain based on $\alpha$?", and make it useful. – Marcus Müller Feb 9 '17 at 15:35
• If you take your title question and put it directly in Google you will find some examples where this has been taught in schools. – SDsolar Feb 24 '17 at 4:00