After many requests we have created a compact, special hybrid balun for Terminated Folded Dipoles (TTFD) and Broad band Terminated Dipole/loop (BBTD) antennas. The CB-9-1-1500 is a CUBE(TM) enclosure containing a multi-core, broadband 9:1 impedance transformer (50 ohm coax input to balanced 450 ohm output) in series with a 1:1 current balun for extra common mode current choking to keep RF current off the outside of the coax braid and on the antenna where it belongs. The extra choking action also means that the coax feed line will not act as a radiator causing unnecessary RF interference (RFI). Rated for full 1500 watts PEP and 450 watts CW (ICAS). 1.8Mhz – 61 MHz.
CB-9-1-1500EB is housed in a 4” x 4” x 2” waterproof housing with SO-239 input and stainless steel eye bolts on the side for ease of connection to your wire antenna. Top eye bolt acts as an antenna hoist. Also available with top studs for post or wall mounting (Model # CB-9-1-1500TS)
Termination resistor for the antenna is a Model # TR-500-600
Many designs for BBTD antennas using 9:1 baluns at HFLINK.COM
Typical user comment:
The filter was quite effective. Was surprised that it actually reduced the noise level more than the signal so S+N/N improved by 1.9 S units. Bill