The MFJ 1838 G3TPW CobWebb Antenna
for the 7, 10, 14, 18, 21, 24, 28 and 50 MHz Bands covers all 8 Bands with low SWR. The SWR at the band edges is mainly reactive, i.e. the resistive component is still near 50 ohms, so auto and simple ATUs can match it with low loss. Over 95% radiation efficiency on all bands! Radiation pattern is nearly omni-directional so you don’t need a rotator.
The eight “squares” are made from white PVC covered multi stranded copper twin cable which is supported by a horizontal cross, made from sky gray fibre glass. Each element is folded and tapped for impedance matching, so that the antenna looks like 50 ohms on all 8 bands. The small size ensures minimum windage and the low weight means that TV type brackets and masts may be used for supports. This eightband half-wave open-loop is perfect for restricted space or portable operation.
It is a very efficient horizontally polarised omni-directional antenna for the 7, 10, 14, 18, 21, 24, 28 and 50 MHz bands, with a gain of 7 dB over an isotropic radiator (7 dBi). Note that this is the same as a standard dipole, although a straight dipole will have sharp nulls off each end. Up to 5 dBi gain will allow you to work DX easily -- even on QRP.
Nearly all the power fed into the CobWebb will be radiated, so the antenna will not heat up and so limit the power rating. CobWebb antennas are not affected by the nearby environment so THEY WORK AT ALL LOCATIONS.
|Minimum SWR|| : ||1.2 :1 or better at 6 m AGL|
|Gain|| : ||4,7 dBi (14.2 MHz at 6 m AGL)|
|Horizontal radiation pattern|| : ||nearly omni-directional|
|Vertical angle of radiation|| : ||37 graden|
|Dimensions|| : ||5,20 x 5,20 m.; diagonal about 7,30 m|
|Matching box|| : ||prefab 1:4 balun incl. coax pigtail with ferrite HF choke and SO 239|
|Connector|| : ||SO 239 (PL female)|
|Mast|| : ||Max. ø 44 mm - 50 mm|
|Max Power|| : ||1500 W PEP (SSB), ICAS (<50% TX)|
|Weight|| : ||13 kg|
To stabilize the antenna, a guying set is included.
Dimensions and weight are including packaging
||L192 x B32 x H16 cm