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:
KPA1500
This RFI Kit Includes are the following filters and installation guidelines:
RF Input:F240 ring – 5-9 turns of RG-58/8X size through center
RF Output:# 1 - FSB31-1 (Big Clamp on) – 3 turns of RG-8 size cable
RF Output:# 2 - FSB31-1 (Big Clamp on) – 3 turns of RG-8 size cable
PA KEY Cable: - FSB31-1/2 – multiple turns through choke – ½” diameter hole
DC Power Line: - FSB31-1 (Big Clamp on) – 2 turns through center
AC Line of DC Power Supply: - FSB31-1 (Big Clamp on) – 3 turns through center
Ports 7 to 15 : - FSB31-1/2 – multiple turns through choke – ½” diameter hole
Total ferrites: - F240 rings (1), FSB31-1 (4), FSB31-1/2 (10)
Also make sure you connect a good RF ground to the amplifier ground post.
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