Tech Support: www.steppir.com/support Tel: 425.891.6134 support@steppir.com
Page 18
REVERSE DIRECTION (180 deg)
40/30m Driven
20m-6m Director
ANTENNA CONFIGURATION GUIDE
FORWARD DIRECTION (Normal)
The DB18 Yagi antenna uses loop elements for 30m and 40M performance. The loop elements used for 40m
and 30m are 40% shorter than a full size element, with very little sacrifice in performance (-0.3dB).
The DB18 uses an integral coax switch to select which one of the three elements are driven to give equal
performance in forward and reverse directions. Each of the loop elements has a relay inside of the EHU.
The control of the antenna and coax switch is integrated into the SDA100 controller for effortless tuning.
The DB18 is a 2 element Yagi on 40m. It has two elements on 30m as well, but because of the wide spac-
ing between elements, the antenna performs more like a high gain dipole on this band. The DB18 has 3 ele-
ments on 20m-6m. An optional 6m passive element kit is available.
The drawing below shows the element configuration of the DB18, so you can better understand what is
happening when you push the buttons on the SDA100 controller!
40m, 20-6m Reflector
30m Driven
RELAY
INSIDE
EHU
RELAY
INSIDE
EHU
NO RELAY
20m-6m Driven
20m-6m Driven
40m, 20m-6m Reflector
40m Driven
20m-6m Director
Optional 6m Passive Element
This element not used when on 40m & 30m This element not used when on 40m & 30m
PREAMBLE
To Next Page
Loading...
