The CD78Jr is a super reduce scaled, 2-band dipole antenna for both 3.5MHz and 3.8MHz bands.
The entirelength of antenna element is 11.9m long which is 28~30% reduce scaled of mechanical length of full-sized antenna. In order to enhance electrical performance better, Hi-Q refurbished high power capable loading coil and a stealth type of capacity-hat are suitably used comparatively, which make it possible to assure approximately -2dB of radiational efficiency against full-scaled length that is considered to be incomparable against a full-sized dipole antenna. In the feed section, a 5-channel matching coupler model BS81, consists of matching coil, relay and high power capable balan transformer is used which enables to derive a low VSWR and high RF power radiational efficiency. This controller for channel swichting is provided standard as an assembly kit form. A 12VDC power supply and 7 conductors control cable are required for this channel switching.
TheVSWR of CD78 is less than 2:1 and allowable bandwidth per channel is approximately 35kHz for both 3.5 and 3.8MHz. Mechanically, a much attention to the selected materials and structural design has also been taken into consideration in this CD78. In couple with a selected high tension aluminum materials, swage-processed tubing are used for element tubings in order to reduce an unnecessary weight and wind surface area.
- Frequency 3.50, 3.53, 3.56, 3.75, 3.80 MHz
- Gain -2dBi
- Impedance 50 Ω
- VSWR at Resonance Less Than1.3
- Power Capability CW/SSB 0.6/1.2kW
- Element Length Approx. 11.9 m
- Weight Element: 6 . 0 k g
- Coupler: 1.0 kg
- MastDiameter φ ～48 61mm
- Wind Load Capability 35m/s