[TowerTalk] HF LOG-PERIODIC ANTENNAS Comments Please

[Jim Lux]

Could you publish the model you used, including the length and type of
feedline you assumed?  I'm assuming that you're talking about out-of -band
mismatch loss?



----- Original Message -----
From: "Larry Phipps" <larry at telepostinc.com>
To: <Towertalk at contesting.com>
Sent: Wednesday, June 23, 2004 12:28 AM
Subject: Re: [TowerTalk] HF LOG-PERIODIC ANTENNAS Comments Please



I just ran a quick sweep of a 3el SteppIR model and the loss in the feedline
alone due to mismatch is about 4dB at 1 mHz out and 10dB at 5 mHz out. Add
to that the pattern loss and you're well over 10dB total out-of-band loss
compared to a LPDA. That might not seem like much, but 10dB lower
interfering signal is roughly 20dB lower distortion products. It all adds
up.