The ZS6BKW antenna is a better match for our bands than the G5RV. The method of construction and tuning is essentially the same for both antennas but the dimensions are different.
Here is the ZS6BKW antenna installed at AK6R fine tuned for the CW/FT8 frequencies on 40-20-17-12-10 meters. An excellent antenna when installed at 30 feet or higher and no tuner required avoiding the tuner losses and constant retuning. If you want to work all bands from 80-10 install an antenna tuner between the 1:1 balun and the amplifier and ignore the 39/40 switch.
Is this the best FT8 antenna? – I think so as I has made over 70,000 contacts and it still is a proven winner -Good world wide DX, easy to install, no tuner and takes full legal limit.
Here are several different 1:1 baluns you can use depending on power requirements:
High Power rated at 2KW/5KW (option) PEP (FT8 mode at 1.5KW for 5KW PEP model)
Broad frequency range of 1.8-61 MHz for < 2:1 SWR into matched load. 5KW model is 1.8-31 MHz
Compact 4" x 4" x 2" (2KW) or 4" x 4" x 2" (5KW) light weight weatherproof enclosure
Quick, easy deployment with either halyard hoist or side mounting tabs
Choice of BALUN (balanced outputs) or UNUN (unbalanced output and ground)
Model CB-2-2000 is a 2:1 (100:50) quad core balun used to translate a 50 ohm input to 100 ohms at RF power levels up to 2000 watts PEP when used with a matched load such as single band delta loop, quad or loop skywire. This assembled balun features a multi-core configuration for increased power handling and flatter frequency response to over 60 MHz. With a matched 100 ohm load the SWR over the frequency range is very consistent from 1.8-61 MHz and SWR is less than 2:1 over the range allowing easy tuning by most radio internal antenna tuners or an external tuner.
Here is the Coax Noise Filter used to suppress coax common mode currents (works for all type of antennas)
PDF of ZS6BKW at AK6R Construction Article HERE: My ZS6BKW Antenna