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W1VT

Joined: Sat, Apr 4th 1998, 00:00 Roles: Super Moderator Moderates: N/A

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QST Downloads Feb 19th 2016, 16:34 5 6,779 on 25/4/20
March 2016 QST Compact Multiband Dipole Feb 19th 2016, 15:23 1 3,954 on 19/2/16
Antenna analyzer vs feedline type Sep 21st 2012, 14:37 1 5,483 on 21/9/12
USB to Serial Port problems--Prolific Drivers Aug 3rd 2012, 18:27 2 6,467 on 26/12/15
Italian Phishing emails! Dec 13th 2011, 14:20 1 5,065 on 13/12/11
John K0GMO needs help designing SS Amp Nov 17th 2011, 15:53 1 5,146 on 17/11/11
1 Farad Capacitor to Eliminate Headlight Flicker? Oct 19th 2011, 13:14 4 7,073 on 9/11/11
History of Relay Rack Dimensions? Oct 17th 2011, 12:58 2 5,117 on 25/10/11
Miswired Selsyn Oct 13th 2011, 17:51 1 5,232 on 13/10/11
Stealth Antenna wire Sep 12th 2011, 12:51 2 5,830 on 13/9/11

Latest Posts

Topic Author Posted On
Effect of nearby metal roof on HF and VHF antenna KA0GWU 2 days, 23 hours ago
The most practical way to see the difference is with on the air testing. Pay particular attention to the noise level on the different bands. Hamspots.net will collect FT8 signal reports for you. The Reverse Beacon Network can be used to collect CW signal reports.

Zak W1VT
ARRL Senior Lab Engineer
Effect of nearby metal roof on HF and VHF antenna KA0GWU 3 days, 18 hours ago
You may want to figure some way of using the metal roof as the ground plane for the Hustler vertical antenna.

Zak W1VT
ARRL Senior Lab Engineer
Tilt on Ground Plane Antennae N1CAK 1 week, 1 day ago
2M FM differs from HF in that with HF, relatively small improvements may allow hearing another layer of weaker stations. There are lot of modest HF stations and relatively few stations running beams on towers with amplifiers. It is possible to make a significant improvement on 2M FM and not significantly improve the number of folks you can reach. Your signal runs into a hill and won't go much farther. In some places, there is nobody else within a reasonable distance to reach.

With VHF propagation, the first 100 miles is hard. Then it gets much easier out to 250 miles. It makes more sense to think of improvements if you can reach a lot of people 100 miles away versus 50 miles away.

Many antennas require constant maintenance in a marine environment. You may want to factor that in when deciding to make changes to the antenna.

Zak W1VT
Tilt on Ground Plane Antennae N1CAK 1 week, 1 day ago
A major component of the antenna pattern is the interaction with the ground. As the antenna gets higher the interaction is disturbed less by the ground, so the changed interactions due to tilt with the ground should be negligible that high up.

A bigger concern, for those who want an ideal installation, is the interaction of the antenna with the feedline and possible mounting structures.

https://forums.qrz.com/index.php?threads/rf-current-flow-on-coax-shield-od-of-ground-plane-antenna.607093/page-2

The AEA isopole decouples the shield better than most.
https://wireless-girl.com/Projects/Antennas/AEAisopole.html

It can be tedious and time consuming to accurately model the mast and feedline with an antenna modeling program, so it is rarely done.

Zak W1VT
ARRL Senior Lab Engineer
bonding two distant 8' copper grounding rods arrl2020 3 weeks, 2 days ago
This illustrated page, by Tom W8JI, discusses your options.
https://www.w8ji.com/house_ground_layouts.htm

He suggests setting up a single point ground for the desk area.
"EVERYTHING on the desk or connected to the operating desk in the radio room has to run from the room common point entrance. No exceptions!"

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