One where to create a 3 meter vertical half-wave dipole with a Rangemaster as the center insulator? Performance better or worse, assuming a match could be obtained with the internal device?
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What If?
- Thread starter druidhillsradio
- Start date
druidhillsradio said:
A vertical, 3-meter long, center-fed dipole would not be a 1/2-wavelength radiator in the medium wave band, but anyway -- near the earth it would have a feedpoint impedance of about 0.1 -j 10,700 ohms at the high end of the AM broadcast band.
So assuming that the transmitter could be matched into that antenna load, it could radiate rather well - depending on the r-f loss and Q (bandwidth) of the matching network. The coupling of the dipole into the service wires connected to the transmitter including the "safety ground" could be a problem for stable tuning, and raise issues with 15.219(b) unless the lower tip of the lower arm of the dipole was very near the surface of the earth.
Other things equal, it might not radiate as well as a 3-meter, base fed, resonated vertical with its base at grade level, using a good r-f ground such as buried radials.
RF
OK. TNX. 
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