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:
RG-8X male to male antenna cable for ham radio, CB and Short wave listening (SWL). This cable is 50 ohm and 3 feet long double shielded with foil and braid with PL-259 connectors on each end. All the connections inside are soldered and the cable is made of copper conductors with coax having PVC jacket. RG-8X is generally good up to 1500 watts PEP at HF frequencies below 30 MHz.
Use for short jumper for Palomar Engineers Noise Filters like CMNF-500-50 or use with Simple Dipole Feed line Choke (SDFLC) to make a 10 turn feed line choke. Also useful between radio devices such as transceiver and amplifier, SWR meter, etc.
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