29 Apr 2023

Multiband antennas

Quite a good multi-band antenna is the end-fed via a 9:1 balun. At the end of the wire it presents a high impedance and the 9:1 balun drops the impedance to a low SWR, certainly less than 3:1 that can be tuned via the auto-ATU in many modern rigs. On many radios an ATU will not be needed at all. With QRP, RF on the coax is not usually an issue. With high power, more care or a counterpoise may be needed.

At the moment I am using an end-fed antenna. I have not found a counterpoise necessary.

Commercial versions are available (e.g. from Moonraker), although many make their own.

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