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Does anyone have experience with building an LPDA antenna. I would mainly be interested in where the coax power supply is connected. before. Either in front or behind the antenna. I will be grateful for any contribution.
Miro.
@terabit wrote:
Does anyone have experience with building an LPDA antenna. I would mainly be interested in where the coax power supply is connected. before. Either in front or behind the antenna. I will be grateful for any contribution.
Miro.
The LPDA for VHF has a short circuit at the point of anchorage to the mast, with which it is fine-tuned, so the power supply is at the open end. You run the coax longitudinally in the lower boom, below (pay attention) pripajas at its end, alive in the same place on the upper boom. http://www.qsl.net/oe7opj/1_lpda/
@OM0ATO wrote:
@terabit wrote:
Does anyone have experience with building an LPDA antenna. I would mainly be interested in where the coax power supply is connected. before. Either in front or behind the antenna. I will be grateful for any contribution.
Miro.
The LPDA for VHF has a short circuit at the point of anchorage to the mast, with which it is fine-tuned, so the power supply is at the open end. You run the coax longitudinally in the lower boom, below (pay attention) pripajas at its end, alive in the same place on the upper boom. http://www.qsl.net/oe7opj/1_lpda/
Good construction. I would need LPDA at 408/1420MHz. You don't have a universal formula for it?
Astrorudy@Astrorudy wrote:
@OM0ATO wrote:
@terabit wrote:
Does anyone have experience with building an LPDA antenna. I would mainly be interested in where the coax power supply is connected. before. Either in front or behind the antenna. I will be grateful for any contribution.
Miro.
The LPDA for VHF has a short circuit at the point of anchorage to the mast, with which it is fine-tuned, so the power supply is at the open end. You run the coax longitudinally in the lower boom, below (pay attention) pripajas at its end, alive in the same place on the upper boom. http://www.qsl.net/oe7opj/1_lpda/
Good construction. I would need LPDA at 408/1420MHz. You don't have a universal formula for it?
AstrorudyNot, I did not try go GSM, but there is some excel script on the net, just google it.
