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Coax RF Choke
Hustler
®
recommends a wound coax type of choke to help prevent RF feedback into the radio room.
The following diagram shows the coax cable choke system which offers modest performance on
some bands.
The better alternative is the optional DX Engineering
DXE-VFCC-H05-A Vertical Feedline
Current Choke
which is specifically engineered and manufactured to help eliminate RF feedback
from a resonant vertical antenna. More information on the VFCC can be found in Chapter 6.
Basic Tuning
In a few basic installations adjustment of the antenna to obtain the lowest SWR may not be
necessary. However, a broad, low SWR over an entire band or all bands is an indication of poor
efficiency. If at all possible, the addition of radials will improve performance as detailed in Chapters
4 and 6. For ground mounted installations the length of radials is not critical and they cannot be
used to change the tuning. Elevated system radials are resonant and they need to be pruned to
lengths for the bands that are used.
Slight adjustments of SWR minimums can be made by shortening or lengthening the starting
dimensions between the antenna tubing sections and the traps in performance installations. These
adjustments may not provide enough changes and you will have to proceed with Trap Calibration
for additional tuning instructions in Chapter 7. Do
NOT
cut the antenna tubing.
