The implementation of digital television in Australia uses
VHF channels 6-12 and UHF 28-69 exclusivley.
This simple antenna is designed to cover those frequency allocations.
This is an array of 6 cross-connected dipoles, similar to the Log-Periodic antenna design.
Each λ/2 dipole has been "cut" for the available channels in my service area (Perth WA),
these being; VHF Ch 6/8/11/12 & UHF Ch 29/32 (see graphic below).
Inter-element spacing is λ/4 of preceding dipole
(running lowest to highest frequency - also see graphic)
Balun has 1:1 or 4:1 impedance matching: S.O.T. (select on test) for best "off-air" reception.
I have no way of determining; antenna 'impedance' or any variation over the frequency range.
Ideally it would be 75 Ω to match the coaxial cable.
For construction: I recycle, dismantled Australian Hills brand domestic TV aerials.